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id="_modules-django-db-models-base"> <h1>Source code for django.db.models.base</h1><div class="highlight"><pre> <span></span><span class="kn">from</span> <span class="nn">__future__</span> <span class="k">import</span> <span class="n">unicode_literals</span> <span class="kn">import</span> <span class="nn">copy</span> <span class="kn">import</span> <span class="nn">inspect</span> <span class="kn">import</span> <span class="nn">sys</span> <span class="kn">import</span> <span class="nn">warnings</span> <span class="kn">from</span> <span class="nn">itertools</span> <span class="k">import</span> <span class="n">chain</span> <span class="kn">from</span> <span class="nn">django.apps</span> <span class="k">import</span> <span class="n">apps</span> <span class="kn">from</span> <span class="nn">django.apps.config</span> <span class="k">import</span> <span class="n">MODELS_MODULE_NAME</span> <span class="kn">from</span> <span class="nn">django.conf</span> <span class="k">import</span> <span class="n">settings</span> <span class="kn">from</span> <span class="nn">django.core</span> <span class="k">import</span> <span class="n">checks</span> <span class="kn">from</span> <span class="nn">django.core.exceptions</span> <span class="k">import</span> <span class="p">(</span> <span class="n">NON_FIELD_ERRORS</span><span class="p">,</span> <span class="n">FieldDoesNotExist</span><span class="p">,</span> <span class="n">FieldError</span><span class="p">,</span> <span class="n">ImproperlyConfigured</span><span class="p">,</span> <span class="n">MultipleObjectsReturned</span><span class="p">,</span> <span class="n">ObjectDoesNotExist</span><span class="p">,</span> <span class="n">ValidationError</span><span class="p">,</span> <span class="p">)</span> <span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="p">(</span> <span class="n">DEFAULT_DB_ALIAS</span><span class="p">,</span> <span class="n">DJANGO_VERSION_PICKLE_KEY</span><span class="p">,</span> <span class="n">DatabaseError</span><span class="p">,</span> <span class="n">connections</span><span class="p">,</span> <span class="n">router</span><span class="p">,</span> <span class="n">transaction</span><span class="p">,</span> <span class="p">)</span> <span class="kn">from</span> <span class="nn">django.db.models</span> <span class="k">import</span> <span class="n">signals</span> <span class="kn">from</span> <span class="nn">django.db.models.constants</span> <span class="k">import</span> <span class="n">LOOKUP_SEP</span> <span class="kn">from</span> <span class="nn">django.db.models.deletion</span> <span class="k">import</span> <span class="n">Collector</span> <span class="kn">from</span> <span class="nn">django.db.models.fields</span> <span class="k">import</span> <span class="n">AutoField</span> <span class="kn">from</span> <span class="nn">django.db.models.fields.related</span> <span class="k">import</span> <span class="p">(</span> <span class="n">ForeignObjectRel</span><span class="p">,</span> <span class="n">ManyToOneRel</span><span class="p">,</span> <span class="n">OneToOneField</span><span class="p">,</span> <span class="n">add_lazy_relation</span><span class="p">,</span> <span class="p">)</span> <span class="kn">from</span> <span class="nn">django.db.models.manager</span> <span class="k">import</span> <span class="n">ensure_default_manager</span> <span class="kn">from</span> <span class="nn">django.db.models.options</span> <span class="k">import</span> <span class="n">Options</span> <span class="kn">from</span> <span class="nn">django.db.models.query</span> <span class="k">import</span> <span class="n">Q</span> <span class="kn">from</span> <span class="nn">django.db.models.query_utils</span> <span class="k">import</span> <span class="p">(</span> <span class="n">DeferredAttribute</span><span class="p">,</span> <span class="n">deferred_class_factory</span><span class="p">,</span> <span class="p">)</span> <span class="kn">from</span> <span class="nn">django.utils</span> <span class="k">import</span> <span class="n">six</span> <span class="kn">from</span> <span class="nn">django.utils.deprecation</span> <span class="k">import</span> <span class="n">RemovedInDjango19Warning</span> <span class="kn">from</span> <span class="nn">django.utils.encoding</span> <span class="k">import</span> <span class="n">force_str</span><span class="p">,</span> <span class="n">force_text</span> <span class="kn">from</span> <span class="nn">django.utils.functional</span> <span class="k">import</span> <span class="n">curry</span> <span class="kn">from</span> <span class="nn">django.utils.six.moves</span> <span class="k">import</span> <span class="nb">zip</span> <span class="kn">from</span> <span class="nn">django.utils.text</span> <span class="k">import</span> <span class="n">capfirst</span><span class="p">,</span> <span class="n">get_text_list</span> <span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="k">import</span> <span class="n">ugettext_lazy</span> <span class="k">as</span> <span class="n">_</span> <span class="kn">from</span> <span class="nn">django.utils.version</span> <span class="k">import</span> <span class="n">get_version</span> <span class="k">def</span> <span class="nf">subclass_exception</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">parents</span><span class="p">,</span> <span class="n">module</span><span class="p">,</span> <span class="n">attached_to</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Create exception subclass. Used by ModelBase below.</span> <span class="sd"> If 'attached_to' is supplied, the exception will be created in a way that</span> <span class="sd"> allows it to be pickled, assuming the returned exception class will be added</span> <span class="sd"> as an attribute to the 'attached_to' class.</span> <span class="sd"> """</span> <span class="n">class_dict</span> <span class="o">=</span> <span class="p">{</span><span class="s1">'__module__'</span><span class="p">:</span> <span class="n">module</span><span class="p">}</span> <span class="k">if</span> <span class="n">attached_to</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="k">def</span> <span class="nf">__reduce__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="c1"># Exceptions are special - they've got state that isn't</span> <span class="c1"># in self.__dict__. We assume it is all in self.args.</span> <span class="k">return</span> <span class="p">(</span><span class="n">unpickle_inner_exception</span><span class="p">,</span> <span class="p">(</span><span class="n">attached_to</span><span class="p">,</span> <span class="n">name</span><span class="p">),</span> <span class="bp">self</span><span class="o">.</span><span class="n">args</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__setstate__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">args</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">args</span> <span class="o">=</span> <span class="n">args</span> <span class="n">class_dict</span><span class="p">[</span><span class="s1">'__reduce__'</span><span class="p">]</span> <span class="o">=</span> <span class="n">__reduce__</span> <span class="n">class_dict</span><span class="p">[</span><span class="s1">'__setstate__'</span><span class="p">]</span> <span class="o">=</span> <span class="n">__setstate__</span> <span class="k">return</span> <span class="nb">type</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">parents</span><span class="p">,</span> <span class="n">class_dict</span><span class="p">)</span> <span class="k">class</span> <span class="nc">ModelBase</span><span class="p">(</span><span class="nb">type</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Metaclass for all models.</span> <span class="sd"> """</span> <span class="k">def</span> <span class="nf">__new__</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">bases</span><span class="p">,</span> <span class="n">attrs</span><span class="p">):</span> <span class="n">super_new</span> <span class="o">=</span> <span class="nb">super</span><span class="p">(</span><span class="n">ModelBase</span><span class="p">,</span> <span class="n">cls</span><span class="p">)</span><span class="o">.</span><span class="n">__new__</span> <span class="c1"># Also ensure initialization is only performed for subclasses of Model</span> <span class="c1"># (excluding Model class itself).</span> <span class="n">parents</span> <span class="o">=</span> <span class="p">[</span><span class="n">b</span> <span class="k">for</span> <span class="n">b</span> <span class="ow">in</span> <span class="n">bases</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">b</span><span class="p">,</span> <span class="n">ModelBase</span><span class="p">)]</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">parents</span><span class="p">:</span> <span class="k">return</span> <span class="n">super_new</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">bases</span><span class="p">,</span> <span class="n">attrs</span><span class="p">)</span> <span class="c1"># Create the class.</span> <span class="n">module</span> <span class="o">=</span> <span class="n">attrs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="s1">'__module__'</span><span class="p">)</span> <span class="n">new_class</span> <span class="o">=</span> <span class="n">super_new</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">bases</span><span class="p">,</span> <span class="p">{</span><span class="s1">'__module__'</span><span class="p">:</span> <span class="n">module</span><span class="p">})</span> <span class="n">attr_meta</span> <span class="o">=</span> <span class="n">attrs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="s1">'Meta'</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="n">abstract</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">attr_meta</span><span class="p">,</span> <span class="s1">'abstract'</span><span class="p">,</span> <span class="kc">False</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">attr_meta</span><span class="p">:</span> <span class="n">meta</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">new_class</span><span class="p">,</span> <span class="s1">'Meta'</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">meta</span> <span class="o">=</span> <span class="n">attr_meta</span> <span class="n">base_meta</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">new_class</span><span class="p">,</span> <span class="s1">'_meta'</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="c1"># Look for an application configuration to attach the model to.</span> <span class="n">app_config</span> <span class="o">=</span> <span class="n">apps</span><span class="o">.</span><span class="n">get_containing_app_config</span><span class="p">(</span><span class="n">module</span><span class="p">)</span> <span class="k">if</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">meta</span><span class="p">,</span> <span class="s1">'app_label'</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">if</span> <span class="n">app_config</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="c1"># If the model is imported before the configuration for its</span> <span class="c1"># application is created (#21719), or isn't in an installed</span> <span class="c1"># application (#21680), use the legacy logic to figure out the</span> <span class="c1"># app_label by looking one level up from the package or module</span> <span class="c1"># named 'models'. If no such package or module exists, fall</span> <span class="c1"># back to looking one level up from the module this model is</span> <span class="c1"># defined in.</span> <span class="c1"># For 'django.contrib.sites.models', this would be 'sites'.</span> <span class="c1"># For 'geo.models.places' this would be 'geo'.</span> <span class="n">msg</span> <span class="o">=</span> <span class="p">(</span> <span class="s2">"Model class </span><span class="si">%s</span><span class="s2">.</span><span class="si">%s</span><span class="s2"> doesn't declare an explicit app_label "</span> <span class="s2">"and either isn't in an application in INSTALLED_APPS or "</span> <span class="s2">"else was imported before its application was loaded. "</span> <span class="s2">"This will no longer be supported in Django 1.9."</span> <span class="o">%</span> <span class="p">(</span><span class="n">module</span><span class="p">,</span> <span class="n">name</span><span class="p">))</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">abstract</span><span class="p">:</span> <span class="n">warnings</span><span class="o">.</span><span class="n">warn</span><span class="p">(</span><span class="n">msg</span><span class="p">,</span> <span class="n">RemovedInDjango19Warning</span><span class="p">,</span> <span class="n">stacklevel</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span> <span class="n">model_module</span> <span class="o">=</span> <span class="n">sys</span><span class="o">.</span><span class="n">modules</span><span class="p">[</span><span class="n">new_class</span><span class="o">.</span><span class="n">__module__</span><span class="p">]</span> <span class="n">package_components</span> <span class="o">=</span> <span class="n">model_module</span><span class="o">.</span><span class="n">__name__</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s1">'.'</span><span class="p">)</span> <span class="n">package_components</span><span class="o">.</span><span class="n">reverse</span><span class="p">()</span> <span class="c1"># find the last occurrence of 'models'</span> <span class="k">try</span><span class="p">:</span> <span class="n">app_label_index</span> <span class="o">=</span> <span class="n">package_components</span><span class="o">.</span><span class="n">index</span><span class="p">(</span><span class="n">MODELS_MODULE_NAME</span><span class="p">)</span> <span class="o">+</span> <span class="mi">1</span> <span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span> <span class="n">app_label_index</span> <span class="o">=</span> <span class="mi">1</span> <span class="k">try</span><span class="p">:</span> <span class="n">kwargs</span> <span class="o">=</span> <span class="p">{</span><span class="s2">"app_label"</span><span class="p">:</span> <span class="n">package_components</span><span class="p">[</span><span class="n">app_label_index</span><span class="p">]}</span> <span class="k">except</span> <span class="ne">IndexError</span><span class="p">:</span> <span class="k">raise</span> <span class="n">ImproperlyConfigured</span><span class="p">(</span> <span class="s1">'Unable to detect the app label for model "</span><span class="si">%s</span><span class="s1">." '</span> <span class="s1">'Ensure that its module, "</span><span class="si">%s</span><span class="s1">", is located inside an installed '</span> <span class="s1">'app.'</span> <span class="o">%</span> <span class="p">(</span><span class="n">new_class</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="n">model_module</span><span class="o">.</span><span class="n">__name__</span><span class="p">)</span> <span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">kwargs</span> <span class="o">=</span> <span class="p">{</span><span class="s2">"app_label"</span><span class="p">:</span> <span class="n">app_config</span><span class="o">.</span><span class="n">label</span><span class="p">}</span> <span class="k">else</span><span class="p">:</span> <span class="n">kwargs</span> <span class="o">=</span> <span class="p">{}</span> <span class="n">new_class</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span><span class="s1">'_meta'</span><span class="p">,</span> <span class="n">Options</span><span class="p">(</span><span class="n">meta</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">))</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">abstract</span><span class="p">:</span> <span class="n">new_class</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span> <span class="s1">'DoesNotExist'</span><span class="p">,</span> <span class="n">subclass_exception</span><span class="p">(</span> <span class="nb">str</span><span class="p">(</span><span class="s1">'DoesNotExist'</span><span class="p">),</span> <span class="nb">tuple</span><span class="p">(</span> <span class="n">x</span><span class="o">.</span><span class="n">DoesNotExist</span> <span class="k">for</span> <span class="n">x</span> <span class="ow">in</span> <span class="n">parents</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="s1">'_meta'</span><span class="p">)</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">x</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">abstract</span> <span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="n">ObjectDoesNotExist</span><span class="p">,),</span> <span class="n">module</span><span class="p">,</span> <span class="n">attached_to</span><span class="o">=</span><span class="n">new_class</span><span class="p">))</span> <span class="n">new_class</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span> <span class="s1">'MultipleObjectsReturned'</span><span class="p">,</span> <span class="n">subclass_exception</span><span class="p">(</span> <span class="nb">str</span><span class="p">(</span><span class="s1">'MultipleObjectsReturned'</span><span class="p">),</span> <span class="nb">tuple</span><span class="p">(</span> <span class="n">x</span><span class="o">.</span><span class="n">MultipleObjectsReturned</span> <span class="k">for</span> <span class="n">x</span> <span class="ow">in</span> <span class="n">parents</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="s1">'_meta'</span><span class="p">)</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">x</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">abstract</span> <span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="n">MultipleObjectsReturned</span><span class="p">,),</span> <span class="n">module</span><span class="p">,</span> <span class="n">attached_to</span><span class="o">=</span><span class="n">new_class</span><span class="p">))</span> <span class="k">if</span> <span class="n">base_meta</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">base_meta</span><span class="o">.</span><span class="n">abstract</span><span class="p">:</span> <span class="c1"># Non-abstract child classes inherit some attributes from their</span> <span class="c1"># non-abstract parent (unless an ABC comes before it in the</span> <span class="c1"># method resolution order).</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">meta</span><span class="p">,</span> <span class="s1">'ordering'</span><span class="p">):</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">ordering</span> <span class="o">=</span> <span class="n">base_meta</span><span class="o">.</span><span class="n">ordering</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">meta</span><span class="p">,</span> <span class="s1">'get_latest_by'</span><span class="p">):</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_latest_by</span> <span class="o">=</span> <span class="n">base_meta</span><span class="o">.</span><span class="n">get_latest_by</span> <span class="n">is_proxy</span> <span class="o">=</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">proxy</span> <span class="c1"># If the model is a proxy, ensure that the base class</span> <span class="c1"># hasn't been swapped out.</span> <span class="k">if</span> <span class="n">is_proxy</span> <span class="ow">and</span> <span class="n">base_meta</span> <span class="ow">and</span> <span class="n">base_meta</span><span class="o">.</span><span class="n">swapped</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"</span><span class="si">%s</span><span class="s2"> cannot proxy the swapped model '</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">base_meta</span><span class="o">.</span><span class="n">swapped</span><span class="p">))</span> <span class="k">if</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">new_class</span><span class="p">,</span> <span class="s1">'_default_manager'</span><span class="p">,</span> <span class="kc">None</span><span class="p">):</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">is_proxy</span><span class="p">:</span> <span class="c1"># Multi-table inheritance doesn't inherit default manager from</span> <span class="c1"># parents.</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_default_manager</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_base_manager</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># Proxy classes do inherit parent's default manager, if none is</span> <span class="c1"># set explicitly.</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_default_manager</span> <span class="o">=</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_default_manager</span><span class="o">.</span><span class="n">_copy_to_model</span><span class="p">(</span><span class="n">new_class</span><span class="p">)</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_base_manager</span> <span class="o">=</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_base_manager</span><span class="o">.</span><span class="n">_copy_to_model</span><span class="p">(</span><span class="n">new_class</span><span class="p">)</span> <span class="c1"># Add all attributes to the class.</span> <span class="k">for</span> <span class="n">obj_name</span><span class="p">,</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">attrs</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="n">new_class</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span><span class="n">obj_name</span><span class="p">,</span> <span class="n">obj</span><span class="p">)</span> <span class="c1"># All the fields of any type declared on this model</span> <span class="n">new_fields</span> <span class="o">=</span> <span class="n">chain</span><span class="p">(</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">,</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_many_to_many</span><span class="p">,</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">virtual_fields</span> <span class="p">)</span> <span class="n">field_names</span> <span class="o">=</span> <span class="p">{</span><span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">new_fields</span><span class="p">}</span> <span class="c1"># Basic setup for proxy models.</span> <span class="k">if</span> <span class="n">is_proxy</span><span class="p">:</span> <span class="n">base</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">for</span> <span class="n">parent</span> <span class="ow">in</span> <span class="p">[</span><span class="n">kls</span> <span class="k">for</span> <span class="n">kls</span> <span class="ow">in</span> <span class="n">parents</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">kls</span><span class="p">,</span> <span class="s1">'_meta'</span><span class="p">)]:</span> <span class="k">if</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">abstract</span><span class="p">:</span> <span class="k">if</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span> <span class="s2">"Abstract base class containing model fields not "</span> <span class="s2">"permitted for proxy model '</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="n">name</span> <span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="k">continue</span> <span class="k">if</span> <span class="n">base</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Proxy model '</span><span class="si">%s</span><span class="s2">' has more than one non-abstract model base class."</span> <span class="o">%</span> <span class="n">name</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">base</span> <span class="o">=</span> <span class="n">parent</span> <span class="k">if</span> <span class="n">base</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Proxy model '</span><span class="si">%s</span><span class="s2">' has no non-abstract model base class."</span> <span class="o">%</span> <span class="n">name</span><span class="p">)</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">setup_proxy</span><span class="p">(</span><span class="n">base</span><span class="p">)</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="o">=</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">proxied_children</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="o">=</span> <span class="n">new_class</span> <span class="c1"># Collect the parent links for multi-table inheritance.</span> <span class="n">parent_links</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">for</span> <span class="n">base</span> <span class="ow">in</span> <span class="nb">reversed</span><span class="p">([</span><span class="n">new_class</span><span class="p">]</span> <span class="o">+</span> <span class="n">parents</span><span class="p">):</span> <span class="c1"># Conceptually equivalent to `if base is Model`.</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">base</span><span class="p">,</span> <span class="s1">'_meta'</span><span class="p">):</span> <span class="k">continue</span> <span class="c1"># Skip concrete parent classes.</span> <span class="k">if</span> <span class="n">base</span> <span class="o">!=</span> <span class="n">new_class</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">abstract</span><span class="p">:</span> <span class="k">continue</span> <span class="c1"># Locate OneToOneField instances.</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">:</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">field</span><span class="p">,</span> <span class="n">OneToOneField</span><span class="p">):</span> <span class="n">parent_links</span><span class="p">[</span><span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">]</span> <span class="o">=</span> <span class="n">field</span> <span class="c1"># Do the appropriate setup for any model parents.</span> <span class="k">for</span> <span class="n">base</span> <span class="ow">in</span> <span class="n">parents</span><span class="p">:</span> <span class="n">original_base</span> <span class="o">=</span> <span class="n">base</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">base</span><span class="p">,</span> <span class="s1">'_meta'</span><span class="p">):</span> <span class="c1"># Things without _meta aren't functional models, so they're</span> <span class="c1"># uninteresting parents.</span> <span class="k">continue</span> <span class="n">parent_fields</span> <span class="o">=</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span> <span class="o">+</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_many_to_many</span> <span class="c1"># Check for clashes between locally declared fields and those</span> <span class="c1"># on the base classes (we cannot handle shadowed fields at the</span> <span class="c1"># moment).</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">parent_fields</span><span class="p">:</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span> <span class="ow">in</span> <span class="n">field_names</span><span class="p">:</span> <span class="k">raise</span> <span class="n">FieldError</span><span class="p">(</span> <span class="s1">'Local field </span><span class="si">%r</span><span class="s1"> in class </span><span class="si">%r</span><span class="s1"> clashes '</span> <span class="s1">'with field of similar name from '</span> <span class="s1">'base class </span><span class="si">%r</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">base</span><span class="o">.</span><span class="n">__name__</span><span class="p">)</span> <span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">abstract</span><span class="p">:</span> <span class="c1"># Concrete classes...</span> <span class="n">base</span> <span class="o">=</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="k">if</span> <span class="n">base</span> <span class="ow">in</span> <span class="n">parent_links</span><span class="p">:</span> <span class="n">field</span> <span class="o">=</span> <span class="n">parent_links</span><span class="p">[</span><span class="n">base</span><span class="p">]</span> <span class="k">elif</span> <span class="ow">not</span> <span class="n">is_proxy</span><span class="p">:</span> <span class="n">attr_name</span> <span class="o">=</span> <span class="s1">'</span><span class="si">%s</span><span class="s1">_ptr'</span> <span class="o">%</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">model_name</span> <span class="n">field</span> <span class="o">=</span> <span class="n">OneToOneField</span><span class="p">(</span><span class="n">base</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="n">attr_name</span><span class="p">,</span> <span class="n">auto_created</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">parent_link</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="c1"># Only add the ptr field if it's not already present;</span> <span class="c1"># e.g. migrations will already have it specified</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">new_class</span><span class="p">,</span> <span class="n">attr_name</span><span class="p">):</span> <span class="n">new_class</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span><span class="n">attr_name</span><span class="p">,</span> <span class="n">field</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">field</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">parents</span><span class="p">[</span><span class="n">base</span><span class="p">]</span> <span class="o">=</span> <span class="n">field</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># .. and abstract ones.</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">parent_fields</span><span class="p">:</span> <span class="n">new_field</span> <span class="o">=</span> <span class="n">copy</span><span class="o">.</span><span class="n">deepcopy</span><span class="p">(</span><span class="n">field</span><span class="p">)</span> <span class="n">new_class</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">new_field</span><span class="p">)</span> <span class="c1"># Pass any non-abstract parent classes onto child.</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">parents</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">parents</span><span class="p">)</span> <span class="c1"># Inherit managers from the abstract base classes.</span> <span class="n">new_class</span><span class="o">.</span><span class="n">copy_managers</span><span class="p">(</span><span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">abstract_managers</span><span class="p">)</span> <span class="c1"># Proxy models inherit the non-abstract managers from their base,</span> <span class="c1"># unless they have redefined any of them.</span> <span class="k">if</span> <span class="n">is_proxy</span><span class="p">:</span> <span class="n">new_class</span><span class="o">.</span><span class="n">copy_managers</span><span class="p">(</span><span class="n">original_base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_managers</span><span class="p">)</span> <span class="c1"># Inherit virtual fields (like GenericForeignKey) from the parent</span> <span class="c1"># class</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">virtual_fields</span><span class="p">:</span> <span class="k">if</span> <span class="n">base</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">abstract</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span> <span class="ow">in</span> <span class="n">field_names</span><span class="p">:</span> <span class="k">raise</span> <span class="n">FieldError</span><span class="p">(</span> <span class="s1">'Local field </span><span class="si">%r</span><span class="s1"> in class </span><span class="si">%r</span><span class="s1"> clashes '</span> <span class="s1">'with field of similar name from '</span> <span class="s1">'abstract base class </span><span class="si">%r</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">base</span><span class="o">.</span><span class="n">__name__</span><span class="p">)</span> <span class="p">)</span> <span class="n">new_class</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">copy</span><span class="o">.</span><span class="n">deepcopy</span><span class="p">(</span><span class="n">field</span><span class="p">))</span> <span class="k">if</span> <span class="n">abstract</span><span class="p">:</span> <span class="c1"># Abstract base models can't be instantiated and don't appear in</span> <span class="c1"># the list of models for an app. We do the final setup for them a</span> <span class="c1"># little differently from normal models.</span> <span class="n">attr_meta</span><span class="o">.</span><span class="n">abstract</span> <span class="o">=</span> <span class="kc">False</span> <span class="n">new_class</span><span class="o">.</span><span class="n">Meta</span> <span class="o">=</span> <span class="n">attr_meta</span> <span class="k">return</span> <span class="n">new_class</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_prepare</span><span class="p">()</span> <span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">apps</span><span class="o">.</span><span class="n">register_model</span><span class="p">(</span><span class="n">new_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">app_label</span><span class="p">,</span> <span class="n">new_class</span><span class="p">)</span> <span class="k">return</span> <span class="n">new_class</span> <span class="k">def</span> <span class="nf">copy_managers</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">base_managers</span><span class="p">):</span> <span class="c1"># This is in-place sorting of an Options attribute, but that's fine.</span> <span class="n">base_managers</span><span class="o">.</span><span class="n">sort</span><span class="p">()</span> <span class="k">for</span> <span class="n">_</span><span class="p">,</span> <span class="n">mgr_name</span><span class="p">,</span> <span class="n">manager</span> <span class="ow">in</span> <span class="n">base_managers</span><span class="p">:</span> <span class="c1"># NOQA (redefinition of _)</span> <span class="n">val</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">mgr_name</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">val</span> <span class="ow">or</span> <span class="n">val</span> <span class="ow">is</span> <span class="n">manager</span><span class="p">:</span> <span class="n">new_manager</span> <span class="o">=</span> <span class="n">manager</span><span class="o">.</span><span class="n">_copy_to_model</span><span class="p">(</span><span class="n">cls</span><span class="p">)</span> <span class="n">cls</span><span class="o">.</span><span class="n">add_to_class</span><span class="p">(</span><span class="n">mgr_name</span><span class="p">,</span> <span class="n">new_manager</span><span class="p">)</span> <span class="k">def</span> <span class="nf">add_to_class</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">value</span><span class="p">):</span> <span class="c1"># We should call the contribute_to_class method only if it's bound</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">inspect</span><span class="o">.</span><span class="n">isclass</span><span class="p">(</span><span class="n">value</span><span class="p">)</span> <span class="ow">and</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="s1">'contribute_to_class'</span><span class="p">):</span> <span class="n">value</span><span class="o">.</span><span class="n">contribute_to_class</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">name</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">value</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_prepare</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Creates some methods once self._meta has been populated.</span> <span class="sd"> """</span> <span class="n">opts</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span> <span class="n">opts</span><span class="o">.</span><span class="n">_prepare</span><span class="p">(</span><span class="n">cls</span><span class="p">)</span> <span class="k">if</span> <span class="n">opts</span><span class="o">.</span><span class="n">order_with_respect_to</span><span class="p">:</span> <span class="n">cls</span><span class="o">.</span><span class="n">get_next_in_order</span> <span class="o">=</span> <span class="n">curry</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_get_next_or_previous_in_order</span><span class="p">,</span> <span class="n">is_next</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="n">cls</span><span class="o">.</span><span class="n">get_previous_in_order</span> <span class="o">=</span> <span class="n">curry</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_get_next_or_previous_in_order</span><span class="p">,</span> <span class="n">is_next</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="c1"># defer creating accessors on the foreign class until we are</span> <span class="c1"># certain it has been created</span> <span class="k">def</span> <span class="nf">make_foreign_order_accessors</span><span class="p">(</span><span class="n">field</span><span class="p">,</span> <span class="n">model</span><span class="p">,</span> <span class="n">cls</span><span class="p">):</span> <span class="nb">setattr</span><span class="p">(</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">,</span> <span class="s1">'get_</span><span class="si">%s</span><span class="s1">_order'</span> <span class="o">%</span> <span class="n">cls</span><span class="o">.</span><span class="n">__name__</span><span class="o">.</span><span class="n">lower</span><span class="p">(),</span> <span class="n">curry</span><span class="p">(</span><span class="n">method_get_order</span><span class="p">,</span> <span class="n">cls</span><span class="p">)</span> <span class="p">)</span> <span class="nb">setattr</span><span class="p">(</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">,</span> <span class="s1">'set_</span><span class="si">%s</span><span class="s1">_order'</span> <span class="o">%</span> <span class="n">cls</span><span class="o">.</span><span class="n">__name__</span><span class="o">.</span><span class="n">lower</span><span class="p">(),</span> <span class="n">curry</span><span class="p">(</span><span class="n">method_set_order</span><span class="p">,</span> <span class="n">cls</span><span class="p">)</span> <span class="p">)</span> <span class="n">add_lazy_relation</span><span class="p">(</span> <span class="n">cls</span><span class="p">,</span> <span class="n">opts</span><span class="o">.</span><span class="n">order_with_respect_to</span><span class="p">,</span> <span class="n">opts</span><span class="o">.</span><span class="n">order_with_respect_to</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">,</span> <span class="n">make_foreign_order_accessors</span> <span class="p">)</span> <span class="c1"># Give the class a docstring -- its definition.</span> <span class="k">if</span> <span class="n">cls</span><span class="o">.</span><span class="n">__doc__</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">cls</span><span class="o">.</span><span class="n">__doc__</span> <span class="o">=</span> <span class="s2">"</span><span class="si">%s</span><span class="s2">(</span><span class="si">%s</span><span class="s2">)"</span> <span class="o">%</span> <span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="s2">", "</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">opts</span><span class="o">.</span><span class="n">fields</span><span class="p">))</span> <span class="n">get_absolute_url_override</span> <span class="o">=</span> <span class="n">settings</span><span class="o">.</span><span class="n">ABSOLUTE_URL_OVERRIDES</span><span class="o">.</span><span class="n">get</span><span class="p">(</span> <span class="s1">'</span><span class="si">%s</span><span class="s1">.</span><span class="si">%s</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">opts</span><span class="o">.</span><span class="n">app_label</span><span class="p">,</span> <span class="n">opts</span><span class="o">.</span><span class="n">model_name</span><span class="p">)</span> <span class="p">)</span> <span class="k">if</span> <span class="n">get_absolute_url_override</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="s1">'get_absolute_url'</span><span class="p">,</span> <span class="n">get_absolute_url_override</span><span class="p">)</span> <span class="n">ensure_default_manager</span><span class="p">(</span><span class="n">cls</span><span class="p">)</span> <span class="n">signals</span><span class="o">.</span><span class="n">class_prepared</span><span class="o">.</span><span class="n">send</span><span class="p">(</span><span class="n">sender</span><span class="o">=</span><span class="n">cls</span><span class="p">)</span> <span class="k">class</span> <span class="nc">ModelState</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> A class for storing instance state</span> <span class="sd"> """</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">db</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">db</span> <span class="c1"># If true, uniqueness validation checks will consider this a new, as-yet-unsaved object.</span> <span class="c1"># Necessary for correct validation of new instances of objects with explicit (non-auto) PKs.</span> <span class="c1"># This impacts validation only; it has no effect on the actual save.</span> <span class="bp">self</span><span class="o">.</span><span class="n">adding</span> <span class="o">=</span> <span class="kc">True</span> <div class="viewcode-block" id="Model"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model">[docs]</a><span class="k">class</span> <span class="nc">Model</span><span class="p">(</span><span class="n">six</span><span class="o">.</span><span class="n">with_metaclass</span><span class="p">(</span><span class="n">ModelBase</span><span class="p">)):</span> <span class="n">_deferred</span> <span class="o">=</span> <span class="kc">False</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="n">signals</span><span class="o">.</span><span class="n">pre_init</span><span class="o">.</span><span class="n">send</span><span class="p">(</span><span class="n">sender</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="n">args</span><span class="o">=</span><span class="n">args</span><span class="p">,</span> <span class="n">kwargs</span><span class="o">=</span><span class="n">kwargs</span><span class="p">)</span> <span class="c1"># Set up the storage for instance state</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span> <span class="o">=</span> <span class="n">ModelState</span><span class="p">()</span> <span class="c1"># There is a rather weird disparity here; if kwargs, it's set, then args</span> <span class="c1"># overrides it. It should be one or the other; don't duplicate the work</span> <span class="c1"># The reason for the kwargs check is that standard iterator passes in by</span> <span class="c1"># args, and instantiation for iteration is 33% faster.</span> <span class="n">args_len</span> <span class="o">=</span> <span class="nb">len</span><span class="p">(</span><span class="n">args</span><span class="p">)</span> <span class="k">if</span> <span class="n">args_len</span> <span class="o">></span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">):</span> <span class="c1"># Daft, but matches old exception sans the err msg.</span> <span class="k">raise</span> <span class="ne">IndexError</span><span class="p">(</span><span class="s2">"Number of args exceeds number of fields"</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">kwargs</span><span class="p">:</span> <span class="n">fields_iter</span> <span class="o">=</span> <span class="nb">iter</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">)</span> <span class="c1"># The ordering of the zip calls matter - zip throws StopIteration</span> <span class="c1"># when an iter throws it. So if the first iter throws it, the second</span> <span class="c1"># is *not* consumed. We rely on this, so don't change the order</span> <span class="c1"># without changing the logic.</span> <span class="k">for</span> <span class="n">val</span><span class="p">,</span> <span class="n">field</span> <span class="ow">in</span> <span class="nb">zip</span><span class="p">(</span><span class="n">args</span><span class="p">,</span> <span class="n">fields_iter</span><span class="p">):</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="n">val</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># Slower, kwargs-ready version.</span> <span class="n">fields_iter</span> <span class="o">=</span> <span class="nb">iter</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">)</span> <span class="k">for</span> <span class="n">val</span><span class="p">,</span> <span class="n">field</span> <span class="ow">in</span> <span class="nb">zip</span><span class="p">(</span><span class="n">args</span><span class="p">,</span> <span class="n">fields_iter</span><span class="p">):</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="n">val</span><span class="p">)</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="c1"># Maintain compatibility with existing calls.</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="p">,</span> <span class="n">ManyToOneRel</span><span class="p">):</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="c1"># Now we're left with the unprocessed fields that *must* come from</span> <span class="c1"># keywords, or default.</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">fields_iter</span><span class="p">:</span> <span class="n">is_related_object</span> <span class="o">=</span> <span class="kc">False</span> <span class="c1"># This slightly odd construct is so that we can access any</span> <span class="c1"># data-descriptor object (DeferredAttribute) without triggering its</span> <span class="c1"># __get__ method.</span> <span class="k">if</span> <span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">kwargs</span> <span class="ow">and</span> <span class="p">(</span><span class="nb">isinstance</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">),</span> <span class="n">DeferredAttribute</span><span class="p">)</span> <span class="ow">or</span> <span class="n">field</span><span class="o">.</span><span class="n">column</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">)):</span> <span class="c1"># This field will be populated on request.</span> <span class="k">continue</span> <span class="k">if</span> <span class="n">kwargs</span><span class="p">:</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="p">,</span> <span class="n">ForeignObjectRel</span><span class="p">):</span> <span class="k">try</span><span class="p">:</span> <span class="c1"># Assume object instance was passed in.</span> <span class="n">rel_obj</span> <span class="o">=</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">)</span> <span class="n">is_related_object</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span> <span class="k">try</span><span class="p">:</span> <span class="c1"># Object instance wasn't passed in -- must be an ID.</span> <span class="n">val</span> <span class="o">=</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span> <span class="n">val</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">get_default</span><span class="p">()</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># Object instance was passed in. Special case: You can</span> <span class="c1"># pass in "None" for related objects if it's allowed.</span> <span class="k">if</span> <span class="n">rel_obj</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">null</span><span class="p">:</span> <span class="n">val</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">else</span><span class="p">:</span> <span class="k">try</span><span class="p">:</span> <span class="n">val</span> <span class="o">=</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span> <span class="c1"># This is done with an exception rather than the</span> <span class="c1"># default argument on pop because we don't want</span> <span class="c1"># get_default() to be evaluated, and then not used.</span> <span class="c1"># Refs #12057.</span> <span class="n">val</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">get_default</span><span class="p">()</span> <span class="k">else</span><span class="p">:</span> <span class="n">val</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">get_default</span><span class="p">()</span> <span class="k">if</span> <span class="n">is_related_object</span><span class="p">:</span> <span class="c1"># If we are passed a related instance, set it using the</span> <span class="c1"># field.name instead of field.attname (e.g. "user" instead of</span> <span class="c1"># "user_id") so that the object gets properly cached (and type</span> <span class="c1"># checked) by the RelatedObjectDescriptor.</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">rel_obj</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="n">val</span><span class="p">)</span> <span class="k">if</span> <span class="n">kwargs</span><span class="p">:</span> <span class="k">for</span> <span class="n">prop</span> <span class="ow">in</span> <span class="nb">list</span><span class="p">(</span><span class="n">kwargs</span><span class="p">):</span> <span class="k">try</span><span class="p">:</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="n">prop</span><span class="p">),</span> <span class="nb">property</span><span class="p">):</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">prop</span><span class="p">,</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">prop</span><span class="p">))</span> <span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span> <span class="k">pass</span> <span class="k">if</span> <span class="n">kwargs</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"'</span><span class="si">%s</span><span class="s2">' is an invalid keyword argument for this function"</span> <span class="o">%</span> <span class="nb">list</span><span class="p">(</span><span class="n">kwargs</span><span class="p">)[</span><span class="mi">0</span><span class="p">])</span> <span class="nb">super</span><span class="p">(</span><span class="n">Model</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">__init__</span><span class="p">()</span> <span class="n">signals</span><span class="o">.</span><span class="n">post_init</span><span class="o">.</span><span class="n">send</span><span class="p">(</span><span class="n">sender</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="n">instance</span><span class="o">=</span><span class="bp">self</span><span class="p">)</span> <span class="nd">@classmethod</span> <div class="viewcode-block" id="Model.from_db"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.from_db">[docs]</a> <span class="k">def</span> <span class="nf">from_db</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">db</span><span class="p">,</span> <span class="n">field_names</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span> <span class="k">if</span> <span class="n">cls</span><span class="o">.</span><span class="n">_deferred</span><span class="p">:</span> <span class="n">new</span> <span class="o">=</span> <span class="n">cls</span><span class="p">(</span><span class="o">**</span><span class="nb">dict</span><span class="p">(</span><span class="nb">zip</span><span class="p">(</span><span class="n">field_names</span><span class="p">,</span> <span class="n">values</span><span class="p">)))</span> <span class="k">else</span><span class="p">:</span> <span class="n">new</span> <span class="o">=</span> <span class="n">cls</span><span class="p">(</span><span class="o">*</span><span class="n">values</span><span class="p">)</span> <span class="n">new</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">adding</span> <span class="o">=</span> <span class="kc">False</span> <span class="n">new</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">db</span> <span class="k">return</span> <span class="n">new</span></div> <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">try</span><span class="p">:</span> <span class="n">u</span> <span class="o">=</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="k">except</span> <span class="p">(</span><span class="ne">UnicodeEncodeError</span><span class="p">,</span> <span class="ne">UnicodeDecodeError</span><span class="p">):</span> <span class="n">u</span> <span class="o">=</span> <span class="s1">'[Bad Unicode data]'</span> <span class="k">return</span> <span class="n">force_str</span><span class="p">(</span><span class="s1">'<</span><span class="si">%s</span><span class="s1">: </span><span class="si">%s</span><span class="s1">>'</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="n">u</span><span class="p">))</span> <div class="viewcode-block" id="Model.__str__"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.__str__">[docs]</a> <span class="k">def</span> <span class="nf">__str__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">if</span> <span class="n">six</span><span class="o">.</span><span class="n">PY2</span> <span class="ow">and</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="s1">'__unicode__'</span><span class="p">):</span> <span class="k">return</span> <span class="n">force_text</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">encode</span><span class="p">(</span><span class="s1">'utf-8'</span><span class="p">)</span> <span class="k">return</span> <span class="s1">'</span><span class="si">%s</span><span class="s1"> object'</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__name__</span></div> <div class="viewcode-block" id="Model.__eq__"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.__eq__">[docs]</a> <span class="k">def</span> <span class="nf">__eq__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span> <span class="n">Model</span><span class="p">):</span> <span class="k">return</span> <span class="kc">False</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="o">!=</span> <span class="n">other</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span><span class="p">:</span> <span class="k">return</span> <span class="kc">False</span> <span class="n">my_pk</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">()</span> <span class="k">if</span> <span class="n">my_pk</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span> <span class="ow">is</span> <span class="n">other</span> <span class="k">return</span> <span class="n">my_pk</span> <span class="o">==</span> <span class="n">other</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">()</span></div> <span class="k">def</span> <span class="nf">__ne__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span> <span class="k">return</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">__eq__</span><span class="p">(</span><span class="n">other</span><span class="p">)</span> <div class="viewcode-block" id="Model.__hash__"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.__hash__">[docs]</a> <span class="k">def</span> <span class="nf">__hash__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">()</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Model instances without primary key value are unhashable"</span><span class="p">)</span> <span class="k">return</span> <span class="nb">hash</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">())</span></div> <span class="k">def</span> <span class="nf">__reduce__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Provides pickling support. Normally, this just dispatches to Python's</span> <span class="sd"> standard handling. However, for models with deferred field loading, we</span> <span class="sd"> need to do things manually, as they're dynamically created classes and</span> <span class="sd"> only module-level classes can be pickled by the default path.</span> <span class="sd"> """</span> <span class="n">data</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span> <span class="n">data</span><span class="p">[</span><span class="n">DJANGO_VERSION_PICKLE_KEY</span><span class="p">]</span> <span class="o">=</span> <span class="n">get_version</span><span class="p">()</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_deferred</span><span class="p">:</span> <span class="n">class_id</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">app_label</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span> <span class="k">return</span> <span class="n">model_unpickle</span><span class="p">,</span> <span class="p">(</span><span class="n">class_id</span><span class="p">,</span> <span class="p">[],</span> <span class="n">simple_class_factory</span><span class="p">),</span> <span class="n">data</span> <span class="n">defers</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">:</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">),</span> <span class="n">DeferredAttribute</span><span class="p">):</span> <span class="n">defers</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="n">model</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">proxy_for_model</span> <span class="n">class_id</span> <span class="o">=</span> <span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">app_label</span><span class="p">,</span> <span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span> <span class="k">return</span> <span class="p">(</span><span class="n">model_unpickle</span><span class="p">,</span> <span class="p">(</span><span class="n">class_id</span><span class="p">,</span> <span class="n">defers</span><span class="p">,</span> <span class="n">deferred_class_factory</span><span class="p">),</span> <span class="n">data</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__setstate__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">state</span><span class="p">):</span> <span class="n">msg</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">pickled_version</span> <span class="o">=</span> <span class="n">state</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">DJANGO_VERSION_PICKLE_KEY</span><span class="p">)</span> <span class="k">if</span> <span class="n">pickled_version</span><span class="p">:</span> <span class="n">current_version</span> <span class="o">=</span> <span class="n">get_version</span><span class="p">()</span> <span class="k">if</span> <span class="n">current_version</span> <span class="o">!=</span> <span class="n">pickled_version</span><span class="p">:</span> <span class="n">msg</span> <span class="o">=</span> <span class="p">(</span><span class="s2">"Pickled model instance's Django version </span><span class="si">%s</span><span class="s2"> does"</span> <span class="s2">" not match the current version </span><span class="si">%s</span><span class="s2">."</span> <span class="o">%</span> <span class="p">(</span><span class="n">pickled_version</span><span class="p">,</span> <span class="n">current_version</span><span class="p">))</span> <span class="k">else</span><span class="p">:</span> <span class="n">msg</span> <span class="o">=</span> <span class="s2">"Pickled model instance's Django version is not specified."</span> <span class="k">if</span> <span class="n">msg</span><span class="p">:</span> <span class="n">warnings</span><span class="o">.</span><span class="n">warn</span><span class="p">(</span><span class="n">msg</span><span class="p">,</span> <span class="ne">RuntimeWarning</span><span class="p">,</span> <span class="n">stacklevel</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">state</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_get_pk_val</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">meta</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">meta</span><span class="p">:</span> <span class="n">meta</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_set_pk_val</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value</span><span class="p">):</span> <span class="k">return</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="n">value</span><span class="p">)</span> <span class="n">pk</span> <span class="o">=</span> <span class="nb">property</span><span class="p">(</span><span class="n">_get_pk_val</span><span class="p">,</span> <span class="n">_set_pk_val</span><span class="p">)</span> <div class="viewcode-block" id="Model.get_deferred_fields"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.get_deferred_fields">[docs]</a> <span class="k">def</span> <span class="nf">get_deferred_fields</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a set containing names of deferred fields for this instance.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="p">{</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">),</span> <span class="n">DeferredAttribute</span><span class="p">)</span> <span class="p">}</span></div> <div class="viewcode-block" id="Model.refresh_from_db"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.refresh_from_db">[docs]</a> <span class="k">def</span> <span class="nf">refresh_from_db</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">fields</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Reloads field values from the database.</span> <span class="sd"> By default, the reloading happens from the database this instance was</span> <span class="sd"> loaded from, or by the read router if this instance wasn't loaded from</span> <span class="sd"> any database. The using parameter will override the default.</span> <span class="sd"> Fields can be used to specify which fields to reload. The fields</span> <span class="sd"> should be an iterable of field attnames. If fields is None, then</span> <span class="sd"> all non-deferred fields are reloaded.</span> <span class="sd"> When accessing deferred fields of an instance, the deferred loading</span> <span class="sd"> of the field will call this method.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="n">fields</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">fields</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">:</span> <span class="k">return</span> <span class="k">if</span> <span class="nb">any</span><span class="p">(</span><span class="n">LOOKUP_SEP</span> <span class="ow">in</span> <span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span> <span class="s1">'Found "</span><span class="si">%s</span><span class="s1">" in fields argument. Relations and transforms '</span> <span class="s1">'are not allowed in fields.'</span> <span class="o">%</span> <span class="n">LOOKUP_SEP</span><span class="p">)</span> <span class="n">db</span> <span class="o">=</span> <span class="n">using</span> <span class="k">if</span> <span class="n">using</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="k">else</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">db</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_deferred</span><span class="p">:</span> <span class="n">non_deferred_model</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">proxy_for_model</span> <span class="k">else</span><span class="p">:</span> <span class="n">non_deferred_model</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span> <span class="n">db_instance_qs</span> <span class="o">=</span> <span class="n">non_deferred_model</span><span class="o">.</span><span class="n">_default_manager</span><span class="o">.</span><span class="n">using</span><span class="p">(</span><span class="n">db</span><span class="p">)</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">pk</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">pk</span><span class="p">)</span> <span class="c1"># Use provided fields, if not set then reload all non-deferred fields.</span> <span class="k">if</span> <span class="n">fields</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="n">fields</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">fields</span><span class="p">)</span> <span class="n">db_instance_qs</span> <span class="o">=</span> <span class="n">db_instance_qs</span><span class="o">.</span><span class="n">only</span><span class="p">(</span><span class="o">*</span><span class="n">fields</span><span class="p">)</span> <span class="k">elif</span> <span class="bp">self</span><span class="o">.</span><span class="n">_deferred</span><span class="p">:</span> <span class="n">deferred_fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_deferred_fields</span><span class="p">()</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">deferred_fields</span><span class="p">]</span> <span class="n">db_instance_qs</span> <span class="o">=</span> <span class="n">db_instance_qs</span><span class="o">.</span><span class="n">only</span><span class="p">(</span><span class="o">*</span><span class="n">fields</span><span class="p">)</span> <span class="n">db_instance</span> <span class="o">=</span> <span class="n">db_instance_qs</span><span class="o">.</span><span class="n">get</span><span class="p">()</span> <span class="n">non_loaded_fields</span> <span class="o">=</span> <span class="n">db_instance</span><span class="o">.</span><span class="n">get_deferred_fields</span><span class="p">()</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">:</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span> <span class="ow">in</span> <span class="n">non_loaded_fields</span><span class="p">:</span> <span class="c1"># This field wasn't refreshed - skip ahead.</span> <span class="k">continue</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">db_instance</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">))</span> <span class="c1"># Throw away stale foreign key references.</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span> <span class="ow">and</span> <span class="n">field</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">()</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="p">:</span> <span class="n">rel_instance</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">())</span> <span class="n">local_val</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">db_instance</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="n">related_val</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">if</span> <span class="n">rel_instance</span> <span class="ow">is</span> <span class="kc">None</span> <span class="k">else</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">rel_instance</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">related_field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">if</span> <span class="n">local_val</span> <span class="o">!=</span> <span class="n">related_val</span> <span class="ow">or</span> <span class="p">(</span><span class="n">local_val</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">and</span> <span class="n">related_val</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">):</span> <span class="k">del</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="p">[</span><span class="n">field</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">()]</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">db_instance</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">db</span></div> <span class="k">def</span> <span class="nf">serializable_value</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field_name</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns the value of the field name for this instance. If the field is</span> <span class="sd"> a foreign key, returns the id value, instead of the object. If there's</span> <span class="sd"> no Field object with this name on the model, the model attribute's</span> <span class="sd"> value is returned directly.</span> <span class="sd"> Used to serialize a field's value (in the serializer, or form output,</span> <span class="sd"> for example). Normally, you would just access the attribute directly</span> <span class="sd"> and not use this method.</span> <span class="sd"> """</span> <span class="k">try</span><span class="p">:</span> <span class="n">field</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_field</span><span class="p">(</span><span class="n">field_name</span><span class="p">)</span> <span class="k">except</span> <span class="n">FieldDoesNotExist</span><span class="p">:</span> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field_name</span><span class="p">)</span> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <div class="viewcode-block" id="Model.save"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.save">[docs]</a> <span class="k">def</span> <span class="nf">save</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">force_insert</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">force_update</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">update_fields</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Saves the current instance. Override this in a subclass if you want to</span> <span class="sd"> control the saving process.</span> <span class="sd"> The 'force_insert' and 'force_update' parameters can be used to insist</span> <span class="sd"> that the "save" must be an SQL insert or update (or equivalent for</span> <span class="sd"> non-SQL backends), respectively. Normally, they should not be set.</span> <span class="sd"> """</span> <span class="c1"># Ensure that a model instance without a PK hasn't been assigned to</span> <span class="c1"># a ForeignKey or OneToOneField on this model. If the field is</span> <span class="c1"># nullable, allowing the save() would result in silent data loss.</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">:</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">is_relation</span><span class="p">:</span> <span class="c1"># If the related field isn't cached, then an instance hasn't</span> <span class="c1"># been assigned and there's no need to worry about this check.</span> <span class="k">try</span><span class="p">:</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">())</span> <span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span> <span class="k">continue</span> <span class="n">obj</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="c1"># A pk may have been assigned manually to a model instance not</span> <span class="c1"># saved to the database (or auto-generated in a case like</span> <span class="c1"># UUIDField), but we allow the save to proceed and rely on the</span> <span class="c1"># database to raise an IntegrityError if applicable. If</span> <span class="c1"># constraints aren't supported by the database, there's the</span> <span class="c1"># unavoidable risk of data corruption.</span> <span class="k">if</span> <span class="n">obj</span> <span class="ow">and</span> <span class="n">obj</span><span class="o">.</span><span class="n">pk</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span> <span class="s2">"save() prohibited to prevent data loss due to "</span> <span class="s2">"unsaved related object '</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span> <span class="p">)</span> <span class="n">using</span> <span class="o">=</span> <span class="n">using</span> <span class="ow">or</span> <span class="n">router</span><span class="o">.</span><span class="n">db_for_write</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="n">instance</span><span class="o">=</span><span class="bp">self</span><span class="p">)</span> <span class="k">if</span> <span class="n">force_insert</span> <span class="ow">and</span> <span class="p">(</span><span class="n">force_update</span> <span class="ow">or</span> <span class="n">update_fields</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"Cannot force both insert and updating in model saving."</span><span class="p">)</span> <span class="k">if</span> <span class="n">update_fields</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="c1"># If update_fields is empty, skip the save. We do also check for</span> <span class="c1"># no-op saves later on for inheritance cases. This bailout is</span> <span class="c1"># still needed for skipping signal sending.</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">update_fields</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">:</span> <span class="k">return</span> <span class="n">update_fields</span> <span class="o">=</span> <span class="nb">frozenset</span><span class="p">(</span><span class="n">update_fields</span><span class="p">)</span> <span class="n">field_names</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">:</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">field</span><span class="o">.</span><span class="n">primary_key</span><span class="p">:</span> <span class="n">field_names</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">)</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span> <span class="o">!=</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">:</span> <span class="n">field_names</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="n">non_model_fields</span> <span class="o">=</span> <span class="n">update_fields</span><span class="o">.</span><span class="n">difference</span><span class="p">(</span><span class="n">field_names</span><span class="p">)</span> <span class="k">if</span> <span class="n">non_model_fields</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"The following fields do not exist in this "</span> <span class="s2">"model or are m2m fields: </span><span class="si">%s</span><span class="s2">"</span> <span class="o">%</span> <span class="s1">', '</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">non_model_fields</span><span class="p">))</span> <span class="c1"># If saving to the same database, and this model is deferred, then</span> <span class="c1"># automatically do a "update_fields" save on the loaded fields.</span> <span class="k">elif</span> <span class="ow">not</span> <span class="n">force_insert</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">_deferred</span> <span class="ow">and</span> <span class="n">using</span> <span class="o">==</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">db</span><span class="p">:</span> <span class="n">field_names</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">:</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">field</span><span class="o">.</span><span class="n">primary_key</span> <span class="ow">and</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">field</span><span class="p">,</span> <span class="s1">'through'</span><span class="p">):</span> <span class="n">field_names</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="n">deferred_fields</span> <span class="o">=</span> <span class="p">[</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span> <span class="k">if</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="ow">not</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span> <span class="ow">and</span> <span class="nb">isinstance</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__dict__</span><span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">],</span> <span class="n">DeferredAttribute</span><span class="p">))</span> <span class="p">]</span> <span class="n">loaded_fields</span> <span class="o">=</span> <span class="n">field_names</span><span class="o">.</span><span class="n">difference</span><span class="p">(</span><span class="n">deferred_fields</span><span class="p">)</span> <span class="k">if</span> <span class="n">loaded_fields</span><span class="p">:</span> <span class="n">update_fields</span> <span class="o">=</span> <span class="nb">frozenset</span><span class="p">(</span><span class="n">loaded_fields</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">save_base</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">,</span> <span class="n">force_insert</span><span class="o">=</span><span class="n">force_insert</span><span class="p">,</span> <span class="n">force_update</span><span class="o">=</span><span class="n">force_update</span><span class="p">,</span> <span class="n">update_fields</span><span class="o">=</span><span class="n">update_fields</span><span class="p">)</span></div> <span class="n">save</span><span class="o">.</span><span class="n">alters_data</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">save_base</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">raw</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">force_insert</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">force_update</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">update_fields</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Handles the parts of saving which should be done only once per save,</span> <span class="sd"> yet need to be done in raw saves, too. This includes some sanity</span> <span class="sd"> checks and signal sending.</span> <span class="sd"> The 'raw' argument is telling save_base not to save any parent</span> <span class="sd"> models and not to do any changes to the values before save. This</span> <span class="sd"> is used by fixture loading.</span> <span class="sd"> """</span> <span class="n">using</span> <span class="o">=</span> <span class="n">using</span> <span class="ow">or</span> <span class="n">router</span><span class="o">.</span><span class="n">db_for_write</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="n">instance</span><span class="o">=</span><span class="bp">self</span><span class="p">)</span> <span class="k">assert</span> <span class="ow">not</span> <span class="p">(</span><span class="n">force_insert</span> <span class="ow">and</span> <span class="p">(</span><span class="n">force_update</span> <span class="ow">or</span> <span class="n">update_fields</span><span class="p">))</span> <span class="k">assert</span> <span class="n">update_fields</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="nb">len</span><span class="p">(</span><span class="n">update_fields</span><span class="p">)</span> <span class="o">></span> <span class="mi">0</span> <span class="n">cls</span> <span class="o">=</span> <span class="n">origin</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span> <span class="c1"># Skip proxies, but keep the origin as the proxy model.</span> <span class="k">if</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">proxy</span><span class="p">:</span> <span class="n">cls</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_model</span> <span class="n">meta</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">meta</span><span class="o">.</span><span class="n">auto_created</span><span class="p">:</span> <span class="n">signals</span><span class="o">.</span><span class="n">pre_save</span><span class="o">.</span><span class="n">send</span><span class="p">(</span><span class="n">sender</span><span class="o">=</span><span class="n">origin</span><span class="p">,</span> <span class="n">instance</span><span class="o">=</span><span class="bp">self</span><span class="p">,</span> <span class="n">raw</span><span class="o">=</span><span class="n">raw</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">,</span> <span class="n">update_fields</span><span class="o">=</span><span class="n">update_fields</span><span class="p">)</span> <span class="k">with</span> <span class="n">transaction</span><span class="o">.</span><span class="n">atomic</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">,</span> <span class="n">savepoint</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">raw</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_save_parents</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">using</span><span class="p">,</span> <span class="n">update_fields</span><span class="p">)</span> <span class="n">updated</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_save_table</span><span class="p">(</span><span class="n">raw</span><span class="p">,</span> <span class="n">cls</span><span class="p">,</span> <span class="n">force_insert</span><span class="p">,</span> <span class="n">force_update</span><span class="p">,</span> <span class="n">using</span><span class="p">,</span> <span class="n">update_fields</span><span class="p">)</span> <span class="c1"># Store the database on which the object was saved</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">using</span> <span class="c1"># Once saved, this is no longer a to-be-added instance.</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">adding</span> <span class="o">=</span> <span class="kc">False</span> <span class="c1"># Signal that the save is complete</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">meta</span><span class="o">.</span><span class="n">auto_created</span><span class="p">:</span> <span class="n">signals</span><span class="o">.</span><span class="n">post_save</span><span class="o">.</span><span class="n">send</span><span class="p">(</span><span class="n">sender</span><span class="o">=</span><span class="n">origin</span><span class="p">,</span> <span class="n">instance</span><span class="o">=</span><span class="bp">self</span><span class="p">,</span> <span class="n">created</span><span class="o">=</span><span class="p">(</span><span class="ow">not</span> <span class="n">updated</span><span class="p">),</span> <span class="n">update_fields</span><span class="o">=</span><span class="n">update_fields</span><span class="p">,</span> <span class="n">raw</span><span class="o">=</span><span class="n">raw</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">)</span> <span class="n">save_base</span><span class="o">.</span><span class="n">alters_data</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">_save_parents</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cls</span><span class="p">,</span> <span class="n">using</span><span class="p">,</span> <span class="n">update_fields</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Saves all the parents of cls using values from self.</span> <span class="sd"> """</span> <span class="n">meta</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span> <span class="k">for</span> <span class="n">parent</span><span class="p">,</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">meta</span><span class="o">.</span><span class="n">parents</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="c1"># Make sure the link fields are synced between parent and self.</span> <span class="k">if</span> <span class="p">(</span><span class="n">field</span> <span class="ow">and</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">and</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">):</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">))</span> <span class="bp">self</span><span class="o">.</span><span class="n">_save_parents</span><span class="p">(</span><span class="n">cls</span><span class="o">=</span><span class="n">parent</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">,</span> <span class="n">update_fields</span><span class="o">=</span><span class="n">update_fields</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_save_table</span><span class="p">(</span><span class="n">cls</span><span class="o">=</span><span class="n">parent</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">,</span> <span class="n">update_fields</span><span class="o">=</span><span class="n">update_fields</span><span class="p">)</span> <span class="c1"># Set the parent's PK value to self.</span> <span class="k">if</span> <span class="n">field</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">(</span><span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="p">))</span> <span class="c1"># Since we didn't have an instance of the parent handy set</span> <span class="c1"># attname directly, bypassing the descriptor. Invalidate</span> <span class="c1"># the related object cache, in case it's been accidentally</span> <span class="c1"># populated. A fresh instance will be re-built from the</span> <span class="c1"># database if necessary.</span> <span class="n">cache_name</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">()</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cache_name</span><span class="p">):</span> <span class="nb">delattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cache_name</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_save_table</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">raw</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">cls</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">force_insert</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">force_update</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">update_fields</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Does the heavy-lifting involved in saving. Updates or inserts the data</span> <span class="sd"> for a single table.</span> <span class="sd"> """</span> <span class="n">meta</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span> <span class="n">non_pks</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">meta</span><span class="o">.</span><span class="n">local_concrete_fields</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">f</span><span class="o">.</span><span class="n">primary_key</span><span class="p">]</span> <span class="k">if</span> <span class="n">update_fields</span><span class="p">:</span> <span class="n">non_pks</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">non_pks</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="ow">in</span> <span class="n">update_fields</span> <span class="ow">or</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="ow">in</span> <span class="n">update_fields</span><span class="p">]</span> <span class="n">pk_val</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">(</span><span class="n">meta</span><span class="p">)</span> <span class="k">if</span> <span class="n">pk_val</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">pk_val</span> <span class="o">=</span> <span class="n">meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">get_pk_value_on_save</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="n">pk_val</span><span class="p">)</span> <span class="n">pk_set</span> <span class="o">=</span> <span class="n">pk_val</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">pk_set</span> <span class="ow">and</span> <span class="p">(</span><span class="n">force_update</span> <span class="ow">or</span> <span class="n">update_fields</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"Cannot force an update in save() with no primary key."</span><span class="p">)</span> <span class="n">updated</span> <span class="o">=</span> <span class="kc">False</span> <span class="c1"># If possible, try an UPDATE. If that doesn't update anything, do an INSERT.</span> <span class="k">if</span> <span class="n">pk_set</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">force_insert</span><span class="p">:</span> <span class="n">base_qs</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_base_manager</span><span class="o">.</span><span class="n">using</span><span class="p">(</span><span class="n">using</span><span class="p">)</span> <span class="n">values</span> <span class="o">=</span> <span class="p">[(</span><span class="n">f</span><span class="p">,</span> <span class="kc">None</span><span class="p">,</span> <span class="p">(</span><span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">if</span> <span class="n">raw</span> <span class="k">else</span> <span class="n">f</span><span class="o">.</span><span class="n">pre_save</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="kc">False</span><span class="p">)))</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">non_pks</span><span class="p">]</span> <span class="n">forced_update</span> <span class="o">=</span> <span class="n">update_fields</span> <span class="ow">or</span> <span class="n">force_update</span> <span class="n">updated</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_do_update</span><span class="p">(</span><span class="n">base_qs</span><span class="p">,</span> <span class="n">using</span><span class="p">,</span> <span class="n">pk_val</span><span class="p">,</span> <span class="n">values</span><span class="p">,</span> <span class="n">update_fields</span><span class="p">,</span> <span class="n">forced_update</span><span class="p">)</span> <span class="k">if</span> <span class="n">force_update</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">updated</span><span class="p">:</span> <span class="k">raise</span> <span class="n">DatabaseError</span><span class="p">(</span><span class="s2">"Forced update did not affect any rows."</span><span class="p">)</span> <span class="k">if</span> <span class="n">update_fields</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">updated</span><span class="p">:</span> <span class="k">raise</span> <span class="n">DatabaseError</span><span class="p">(</span><span class="s2">"Save with update_fields did not affect any rows."</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">updated</span><span class="p">:</span> <span class="k">if</span> <span class="n">meta</span><span class="o">.</span><span class="n">order_with_respect_to</span><span class="p">:</span> <span class="c1"># If this is a model with an order_with_respect_to</span> <span class="c1"># autopopulate the _order field</span> <span class="n">field</span> <span class="o">=</span> <span class="n">meta</span><span class="o">.</span><span class="n">order_with_respect_to</span> <span class="n">order_value</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_base_manager</span><span class="o">.</span><span class="n">using</span><span class="p">(</span><span class="n">using</span><span class="p">)</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span> <span class="o">**</span><span class="p">{</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">:</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)})</span><span class="o">.</span><span class="n">count</span><span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">_order</span> <span class="o">=</span> <span class="n">order_value</span> <span class="n">fields</span> <span class="o">=</span> <span class="n">meta</span><span class="o">.</span><span class="n">local_concrete_fields</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">pk_set</span><span class="p">:</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">f</span><span class="p">,</span> <span class="n">AutoField</span><span class="p">)]</span> <span class="n">update_pk</span> <span class="o">=</span> <span class="nb">bool</span><span class="p">(</span><span class="n">meta</span><span class="o">.</span><span class="n">has_auto_field</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">pk_set</span><span class="p">)</span> <span class="n">result</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_do_insert</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_base_manager</span><span class="p">,</span> <span class="n">using</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">update_pk</span><span class="p">,</span> <span class="n">raw</span><span class="p">)</span> <span class="k">if</span> <span class="n">update_pk</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="n">result</span><span class="p">)</span> <span class="k">return</span> <span class="n">updated</span> <span class="k">def</span> <span class="nf">_do_update</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">base_qs</span><span class="p">,</span> <span class="n">using</span><span class="p">,</span> <span class="n">pk_val</span><span class="p">,</span> <span class="n">values</span><span class="p">,</span> <span class="n">update_fields</span><span class="p">,</span> <span class="n">forced_update</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> This method will try to update the model. If the model was updated (in</span> <span class="sd"> the sense that an update query was done and a matching row was found</span> <span class="sd"> from the DB) the method will return True.</span> <span class="sd"> """</span> <span class="n">filtered</span> <span class="o">=</span> <span class="n">base_qs</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">pk</span><span class="o">=</span><span class="n">pk_val</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">values</span><span class="p">:</span> <span class="c1"># We can end up here when saving a model in inheritance chain where</span> <span class="c1"># update_fields doesn't target any field in current model. In that</span> <span class="c1"># case we just say the update succeeded. Another case ending up here</span> <span class="c1"># is a model with just PK - in that case check that the PK still</span> <span class="c1"># exists.</span> <span class="k">return</span> <span class="n">update_fields</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">filtered</span><span class="o">.</span><span class="n">exists</span><span class="p">()</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">select_on_save</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">forced_update</span><span class="p">:</span> <span class="k">if</span> <span class="n">filtered</span><span class="o">.</span><span class="n">exists</span><span class="p">():</span> <span class="c1"># It may happen that the object is deleted from the DB right after</span> <span class="c1"># this check, causing the subsequent UPDATE to return zero matching</span> <span class="c1"># rows. The same result can occur in some rare cases when the</span> <span class="c1"># database returns zero despite the UPDATE being executed</span> <span class="c1"># successfully (a row is matched and updated). In order to</span> <span class="c1"># distinguish these two cases, the object's existence in the</span> <span class="c1"># database is again checked for if the UPDATE query returns 0.</span> <span class="k">return</span> <span class="n">filtered</span><span class="o">.</span><span class="n">_update</span><span class="p">(</span><span class="n">values</span><span class="p">)</span> <span class="o">></span> <span class="mi">0</span> <span class="ow">or</span> <span class="n">filtered</span><span class="o">.</span><span class="n">exists</span><span class="p">()</span> <span class="k">else</span><span class="p">:</span> <span class="k">return</span> <span class="kc">False</span> <span class="k">return</span> <span class="n">filtered</span><span class="o">.</span><span class="n">_update</span><span class="p">(</span><span class="n">values</span><span class="p">)</span> <span class="o">></span> <span class="mi">0</span> <span class="k">def</span> <span class="nf">_do_insert</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">manager</span><span class="p">,</span> <span class="n">using</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">update_pk</span><span class="p">,</span> <span class="n">raw</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Do an INSERT. If update_pk is defined then this method should return</span> <span class="sd"> the new pk for the model.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="n">manager</span><span class="o">.</span><span class="n">_insert</span><span class="p">([</span><span class="bp">self</span><span class="p">],</span> <span class="n">fields</span><span class="o">=</span><span class="n">fields</span><span class="p">,</span> <span class="n">return_id</span><span class="o">=</span><span class="n">update_pk</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">,</span> <span class="n">raw</span><span class="o">=</span><span class="n">raw</span><span class="p">)</span> <div class="viewcode-block" id="Model.delete"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.delete">[docs]</a> <span class="k">def</span> <span class="nf">delete</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="n">using</span> <span class="o">=</span> <span class="n">using</span> <span class="ow">or</span> <span class="n">router</span><span class="o">.</span><span class="n">db_for_write</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="n">instance</span><span class="o">=</span><span class="bp">self</span><span class="p">)</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">()</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">,</span> <span class="p">(</span> <span class="s2">"</span><span class="si">%s</span><span class="s2"> object can't be deleted because its </span><span class="si">%s</span><span class="s2"> attribute is set to None."</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="p">)</span> <span class="n">collector</span> <span class="o">=</span> <span class="n">Collector</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">)</span> <span class="n">collector</span><span class="o">.</span><span class="n">collect</span><span class="p">([</span><span class="bp">self</span><span class="p">])</span> <span class="n">collector</span><span class="o">.</span><span class="n">delete</span><span class="p">()</span></div> <span class="n">delete</span><span class="o">.</span><span class="n">alters_data</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">_get_FIELD_display</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="p">):</span> <span class="n">value</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">return</span> <span class="n">force_text</span><span class="p">(</span><span class="nb">dict</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">flatchoices</span><span class="p">)</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="n">value</span><span class="p">),</span> <span class="n">strings_only</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_get_next_or_previous_by_FIELD</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="p">,</span> <span class="n">is_next</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"get_next/get_previous cannot be used on unsaved objects."</span><span class="p">)</span> <span class="n">op</span> <span class="o">=</span> <span class="s1">'gt'</span> <span class="k">if</span> <span class="n">is_next</span> <span class="k">else</span> <span class="s1">'lt'</span> <span class="n">order</span> <span class="o">=</span> <span class="s1">''</span> <span class="k">if</span> <span class="n">is_next</span> <span class="k">else</span> <span class="s1">'-'</span> <span class="n">param</span> <span class="o">=</span> <span class="n">force_text</span><span class="p">(</span><span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">))</span> <span class="n">q</span> <span class="o">=</span> <span class="n">Q</span><span class="p">(</span><span class="o">**</span><span class="p">{</span><span class="s1">'</span><span class="si">%s</span><span class="s1">__</span><span class="si">%s</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">op</span><span class="p">):</span> <span class="n">param</span><span class="p">})</span> <span class="n">q</span> <span class="o">=</span> <span class="n">q</span> <span class="o">|</span> <span class="n">Q</span><span class="p">(</span><span class="o">**</span><span class="p">{</span><span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">:</span> <span class="n">param</span><span class="p">,</span> <span class="s1">'pk__</span><span class="si">%s</span><span class="s1">'</span> <span class="o">%</span> <span class="n">op</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span><span class="p">})</span> <span class="n">qs</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">_default_manager</span><span class="o">.</span><span class="n">using</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">db</span><span class="p">)</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o">**</span><span class="n">kwargs</span><span class="p">)</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">q</span><span class="p">)</span><span class="o">.</span><span class="n">order_by</span><span class="p">(</span> <span class="s1">'</span><span class="si">%s%s</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">order</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">),</span> <span class="s1">'</span><span class="si">%s</span><span class="s1">pk'</span> <span class="o">%</span> <span class="n">order</span> <span class="p">)</span> <span class="k">try</span><span class="p">:</span> <span class="k">return</span> <span class="n">qs</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">except</span> <span class="ne">IndexError</span><span class="p">:</span> <span class="k">raise</span> <span class="bp">self</span><span class="o">.</span><span class="n">DoesNotExist</span><span class="p">(</span><span class="s2">"</span><span class="si">%s</span><span class="s2"> matching query does not exist."</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_get_next_or_previous_in_order</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">is_next</span><span class="p">):</span> <span class="n">cachename</span> <span class="o">=</span> <span class="s2">"__</span><span class="si">%s</span><span class="s2">_order_cache"</span> <span class="o">%</span> <span class="n">is_next</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cachename</span><span class="p">):</span> <span class="n">op</span> <span class="o">=</span> <span class="s1">'gt'</span> <span class="k">if</span> <span class="n">is_next</span> <span class="k">else</span> <span class="s1">'lt'</span> <span class="n">order</span> <span class="o">=</span> <span class="s1">'_order'</span> <span class="k">if</span> <span class="n">is_next</span> <span class="k">else</span> <span class="s1">'-_order'</span> <span class="n">order_field</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">order_with_respect_to</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_default_manager</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o">**</span><span class="p">{</span> <span class="n">order_field</span><span class="o">.</span><span class="n">name</span><span class="p">:</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">order_field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="p">})</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o">**</span><span class="p">{</span> <span class="s1">'_order__</span><span class="si">%s</span><span class="s1">'</span> <span class="o">%</span> <span class="n">op</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_default_manager</span><span class="o">.</span><span class="n">values</span><span class="p">(</span><span class="s1">'_order'</span><span class="p">)</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o">**</span><span class="p">{</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">name</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span> <span class="p">})</span> <span class="p">})</span><span class="o">.</span><span class="n">order_by</span><span class="p">(</span><span class="n">order</span><span class="p">)[:</span><span class="mi">1</span><span class="p">]</span><span class="o">.</span><span class="n">get</span><span class="p">()</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cachename</span><span class="p">,</span> <span class="n">obj</span><span class="p">)</span> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">cachename</span><span class="p">)</span> <span class="k">def</span> <span class="nf">prepare_database_save</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"Unsaved model instance </span><span class="si">%r</span><span class="s2"> cannot be used in an ORM query."</span> <span class="o">%</span> <span class="bp">self</span><span class="p">)</span> <span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">get_related_field</span><span class="p">()</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <div class="viewcode-block" id="Model.clean"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.clean">[docs]</a> <span class="k">def</span> <span class="nf">clean</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Hook for doing any extra model-wide validation after clean() has been</span> <span class="sd"> called on every field by self.clean_fields. Any ValidationError raised</span> <span class="sd"> by this method will not be associated with a particular field; it will</span> <span class="sd"> have a special-case association with the field defined by NON_FIELD_ERRORS.</span> <span class="sd"> """</span> <span class="k">pass</span></div> <div class="viewcode-block" id="Model.validate_unique"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.validate_unique">[docs]</a> <span class="k">def</span> <span class="nf">validate_unique</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">exclude</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Checks unique constraints on the model and raises ``ValidationError``</span> <span class="sd"> if any failed.</span> <span class="sd"> """</span> <span class="n">unique_checks</span><span class="p">,</span> <span class="n">date_checks</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_unique_checks</span><span class="p">(</span><span class="n">exclude</span><span class="o">=</span><span class="n">exclude</span><span class="p">)</span> <span class="n">errors</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_perform_unique_checks</span><span class="p">(</span><span class="n">unique_checks</span><span class="p">)</span> <span class="n">date_errors</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_perform_date_checks</span><span class="p">(</span><span class="n">date_checks</span><span class="p">)</span> <span class="k">for</span> <span class="n">k</span><span class="p">,</span> <span class="n">v</span> <span class="ow">in</span> <span class="n">date_errors</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="n">errors</span><span class="o">.</span><span class="n">setdefault</span><span class="p">(</span><span class="n">k</span><span class="p">,</span> <span class="p">[])</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">v</span><span class="p">)</span> <span class="k">if</span> <span class="n">errors</span><span class="p">:</span> <span class="k">raise</span> <span class="n">ValidationError</span><span class="p">(</span><span class="n">errors</span><span class="p">)</span></div> <span class="k">def</span> <span class="nf">_get_unique_checks</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">exclude</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Gather a list of checks to perform. Since validate_unique could be</span> <span class="sd"> called from a ModelForm, some fields may have been excluded; we can't</span> <span class="sd"> perform a unique check on a model that is missing fields involved</span> <span class="sd"> in that check.</span> <span class="sd"> Fields that did not validate should also be excluded, but they need</span> <span class="sd"> to be passed in via the exclude argument.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="n">exclude</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">exclude</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">unique_checks</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">unique_togethers</span> <span class="o">=</span> <span class="p">[(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">unique_together</span><span class="p">)]</span> <span class="k">for</span> <span class="n">parent_class</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_parent_list</span><span class="p">():</span> <span class="k">if</span> <span class="n">parent_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">unique_together</span><span class="p">:</span> <span class="n">unique_togethers</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">parent_class</span><span class="p">,</span> <span class="n">parent_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">unique_together</span><span class="p">))</span> <span class="k">for</span> <span class="n">model_class</span><span class="p">,</span> <span class="n">unique_together</span> <span class="ow">in</span> <span class="n">unique_togethers</span><span class="p">:</span> <span class="k">for</span> <span class="n">check</span> <span class="ow">in</span> <span class="n">unique_together</span><span class="p">:</span> <span class="k">for</span> <span class="n">name</span> <span class="ow">in</span> <span class="n">check</span><span class="p">:</span> <span class="c1"># If this is an excluded field, don't add this check.</span> <span class="k">if</span> <span class="n">name</span> <span class="ow">in</span> <span class="n">exclude</span><span class="p">:</span> <span class="k">break</span> <span class="k">else</span><span class="p">:</span> <span class="n">unique_checks</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">model_class</span><span class="p">,</span> <span class="nb">tuple</span><span class="p">(</span><span class="n">check</span><span class="p">)))</span> <span class="c1"># These are checks for the unique_for_<date/year/month>.</span> <span class="n">date_checks</span> <span class="o">=</span> <span class="p">[]</span> <span class="c1"># Gather a list of checks for fields declared as unique and add them to</span> <span class="c1"># the list of checks.</span> <span class="n">fields_with_class</span> <span class="o">=</span> <span class="p">[(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">)]</span> <span class="k">for</span> <span class="n">parent_class</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_parent_list</span><span class="p">():</span> <span class="n">fields_with_class</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">parent_class</span><span class="p">,</span> <span class="n">parent_class</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">))</span> <span class="k">for</span> <span class="n">model_class</span><span class="p">,</span> <span class="n">fields</span> <span class="ow">in</span> <span class="n">fields_with_class</span><span class="p">:</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">:</span> <span class="n">name</span> <span class="o">=</span> <span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="k">if</span> <span class="n">name</span> <span class="ow">in</span> <span class="n">exclude</span><span class="p">:</span> <span class="k">continue</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">unique</span><span class="p">:</span> <span class="n">unique_checks</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">model_class</span><span class="p">,</span> <span class="p">(</span><span class="n">name</span><span class="p">,)))</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_date</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_date</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">exclude</span><span class="p">:</span> <span class="n">date_checks</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">model_class</span><span class="p">,</span> <span class="s1">'date'</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_date</span><span class="p">))</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_year</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_year</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">exclude</span><span class="p">:</span> <span class="n">date_checks</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">model_class</span><span class="p">,</span> <span class="s1">'year'</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_year</span><span class="p">))</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_month</span> <span class="ow">and</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_month</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">exclude</span><span class="p">:</span> <span class="n">date_checks</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">model_class</span><span class="p">,</span> <span class="s1">'month'</span><span class="p">,</span> <span class="n">name</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">unique_for_month</span><span class="p">))</span> <span class="k">return</span> <span class="n">unique_checks</span><span class="p">,</span> <span class="n">date_checks</span> <span class="k">def</span> <span class="nf">_perform_unique_checks</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">unique_checks</span><span class="p">):</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">for</span> <span class="n">model_class</span><span class="p">,</span> <span class="n">unique_check</span> <span class="ow">in</span> <span class="n">unique_checks</span><span class="p">:</span> <span class="c1"># Try to look up an existing object with the same values as this</span> <span class="c1"># object's values for all the unique field.</span> <span class="n">lookup_kwargs</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">for</span> <span class="n">field_name</span> <span class="ow">in</span> <span class="n">unique_check</span><span class="p">:</span> <span class="n">f</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_field</span><span class="p">(</span><span class="n">field_name</span><span class="p">)</span> <span class="n">lookup_value</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">if</span> <span class="n">lookup_value</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="c1"># no value, skip the lookup</span> <span class="k">continue</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">primary_key</span> <span class="ow">and</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">adding</span><span class="p">:</span> <span class="c1"># no need to check for unique primary key when editing</span> <span class="k">continue</span> <span class="n">lookup_kwargs</span><span class="p">[</span><span class="nb">str</span><span class="p">(</span><span class="n">field_name</span><span class="p">)]</span> <span class="o">=</span> <span class="n">lookup_value</span> <span class="c1"># some fields were skipped, no reason to do the check</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">unique_check</span><span class="p">)</span> <span class="o">!=</span> <span class="nb">len</span><span class="p">(</span><span class="n">lookup_kwargs</span><span class="p">):</span> <span class="k">continue</span> <span class="n">qs</span> <span class="o">=</span> <span class="n">model_class</span><span class="o">.</span><span class="n">_default_manager</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o">**</span><span class="n">lookup_kwargs</span><span class="p">)</span> <span class="c1"># Exclude the current object from the query if we are editing an</span> <span class="c1"># instance (as opposed to creating a new one)</span> <span class="c1"># Note that we need to use the pk as defined by model_class, not</span> <span class="c1"># self.pk. These can be different fields because model inheritance</span> <span class="c1"># allows single model to have effectively multiple primary keys.</span> <span class="c1"># Refs #17615.</span> <span class="n">model_class_pk</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">(</span><span class="n">model_class</span><span class="o">.</span><span class="n">_meta</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">adding</span> <span class="ow">and</span> <span class="n">model_class_pk</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="n">qs</span> <span class="o">=</span> <span class="n">qs</span><span class="o">.</span><span class="n">exclude</span><span class="p">(</span><span class="n">pk</span><span class="o">=</span><span class="n">model_class_pk</span><span class="p">)</span> <span class="k">if</span> <span class="n">qs</span><span class="o">.</span><span class="n">exists</span><span class="p">():</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">unique_check</span><span class="p">)</span> <span class="o">==</span> <span class="mi">1</span><span class="p">:</span> <span class="n">key</span> <span class="o">=</span> <span class="n">unique_check</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">else</span><span class="p">:</span> <span class="n">key</span> <span class="o">=</span> <span class="n">NON_FIELD_ERRORS</span> <span class="n">errors</span><span class="o">.</span><span class="n">setdefault</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="p">[])</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">unique_error_message</span><span class="p">(</span><span class="n">model_class</span><span class="p">,</span> <span class="n">unique_check</span><span class="p">))</span> <span class="k">return</span> <span class="n">errors</span> <span class="k">def</span> <span class="nf">_perform_date_checks</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">date_checks</span><span class="p">):</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">for</span> <span class="n">model_class</span><span class="p">,</span> <span class="n">lookup_type</span><span class="p">,</span> <span class="n">field</span><span class="p">,</span> <span class="n">unique_for</span> <span class="ow">in</span> <span class="n">date_checks</span><span class="p">:</span> <span class="n">lookup_kwargs</span> <span class="o">=</span> <span class="p">{}</span> <span class="c1"># there's a ticket to add a date lookup, we can remove this special</span> <span class="c1"># case if that makes it's way in</span> <span class="n">date</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">unique_for</span><span class="p">)</span> <span class="k">if</span> <span class="n">date</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">continue</span> <span class="k">if</span> <span class="n">lookup_type</span> <span class="o">==</span> <span class="s1">'date'</span><span class="p">:</span> <span class="n">lookup_kwargs</span><span class="p">[</span><span class="s1">'</span><span class="si">%s</span><span class="s1">__day'</span> <span class="o">%</span> <span class="n">unique_for</span><span class="p">]</span> <span class="o">=</span> <span class="n">date</span><span class="o">.</span><span class="n">day</span> <span class="n">lookup_kwargs</span><span class="p">[</span><span class="s1">'</span><span class="si">%s</span><span class="s1">__month'</span> <span class="o">%</span> <span class="n">unique_for</span><span class="p">]</span> <span class="o">=</span> <span class="n">date</span><span class="o">.</span><span class="n">month</span> <span class="n">lookup_kwargs</span><span class="p">[</span><span class="s1">'</span><span class="si">%s</span><span class="s1">__year'</span> <span class="o">%</span> <span class="n">unique_for</span><span class="p">]</span> <span class="o">=</span> <span class="n">date</span><span class="o">.</span><span class="n">year</span> <span class="k">else</span><span class="p">:</span> <span class="n">lookup_kwargs</span><span class="p">[</span><span class="s1">'</span><span class="si">%s</span><span class="s1">__</span><span class="si">%s</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">unique_for</span><span class="p">,</span> <span class="n">lookup_type</span><span class="p">)]</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">date</span><span class="p">,</span> <span class="n">lookup_type</span><span class="p">)</span> <span class="n">lookup_kwargs</span><span class="p">[</span><span class="n">field</span><span class="p">]</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field</span><span class="p">)</span> <span class="n">qs</span> <span class="o">=</span> <span class="n">model_class</span><span class="o">.</span><span class="n">_default_manager</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o">**</span><span class="n">lookup_kwargs</span><span class="p">)</span> <span class="c1"># Exclude the current object from the query if we are editing an</span> <span class="c1"># instance (as opposed to creating a new one)</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_state</span><span class="o">.</span><span class="n">adding</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="n">qs</span> <span class="o">=</span> <span class="n">qs</span><span class="o">.</span><span class="n">exclude</span><span class="p">(</span><span class="n">pk</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">pk</span><span class="p">)</span> <span class="k">if</span> <span class="n">qs</span><span class="o">.</span><span class="n">exists</span><span class="p">():</span> <span class="n">errors</span><span class="o">.</span><span class="n">setdefault</span><span class="p">(</span><span class="n">field</span><span class="p">,</span> <span class="p">[])</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="bp">self</span><span class="o">.</span><span class="n">date_error_message</span><span class="p">(</span><span class="n">lookup_type</span><span class="p">,</span> <span class="n">field</span><span class="p">,</span> <span class="n">unique_for</span><span class="p">)</span> <span class="p">)</span> <span class="k">return</span> <span class="n">errors</span> <span class="k">def</span> <span class="nf">date_error_message</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">lookup_type</span><span class="p">,</span> <span class="n">field_name</span><span class="p">,</span> <span class="n">unique_for</span><span class="p">):</span> <span class="n">opts</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span> <span class="n">field</span> <span class="o">=</span> <span class="n">opts</span><span class="o">.</span><span class="n">get_field</span><span class="p">(</span><span class="n">field_name</span><span class="p">)</span> <span class="k">return</span> <span class="n">ValidationError</span><span class="p">(</span> <span class="n">message</span><span class="o">=</span><span class="n">field</span><span class="o">.</span><span class="n">error_messages</span><span class="p">[</span><span class="s1">'unique_for_date'</span><span class="p">],</span> <span class="n">code</span><span class="o">=</span><span class="s1">'unique_for_date'</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="p">{</span> <span class="s1">'model'</span><span class="p">:</span> <span class="bp">self</span><span class="p">,</span> <span class="s1">'model_name'</span><span class="p">:</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span><span class="p">(</span><span class="n">capfirst</span><span class="p">(</span><span class="n">opts</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">)),</span> <span class="s1">'lookup_type'</span><span class="p">:</span> <span class="n">lookup_type</span><span class="p">,</span> <span class="s1">'field'</span><span class="p">:</span> <span class="n">field_name</span><span class="p">,</span> <span class="s1">'field_label'</span><span class="p">:</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span><span class="p">(</span><span class="n">capfirst</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">)),</span> <span class="s1">'date_field'</span><span class="p">:</span> <span class="n">unique_for</span><span class="p">,</span> <span class="s1">'date_field_label'</span><span class="p">:</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span><span class="p">(</span><span class="n">capfirst</span><span class="p">(</span><span class="n">opts</span><span class="o">.</span><span class="n">get_field</span><span class="p">(</span><span class="n">unique_for</span><span class="p">)</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">)),</span> <span class="p">}</span> <span class="p">)</span> <span class="k">def</span> <span class="nf">unique_error_message</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">model_class</span><span class="p">,</span> <span class="n">unique_check</span><span class="p">):</span> <span class="n">opts</span> <span class="o">=</span> <span class="n">model_class</span><span class="o">.</span><span class="n">_meta</span> <span class="n">params</span> <span class="o">=</span> <span class="p">{</span> <span class="s1">'model'</span><span class="p">:</span> <span class="bp">self</span><span class="p">,</span> <span class="s1">'model_class'</span><span class="p">:</span> <span class="n">model_class</span><span class="p">,</span> <span class="s1">'model_name'</span><span class="p">:</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span><span class="p">(</span><span class="n">capfirst</span><span class="p">(</span><span class="n">opts</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">)),</span> <span class="s1">'unique_check'</span><span class="p">:</span> <span class="n">unique_check</span><span class="p">,</span> <span class="p">}</span> <span class="c1"># A unique field</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">unique_check</span><span class="p">)</span> <span class="o">==</span> <span class="mi">1</span><span class="p">:</span> <span class="n">field</span> <span class="o">=</span> <span class="n">opts</span><span class="o">.</span><span class="n">get_field</span><span class="p">(</span><span class="n">unique_check</span><span class="p">[</span><span class="mi">0</span><span class="p">])</span> <span class="n">params</span><span class="p">[</span><span class="s1">'field_label'</span><span class="p">]</span> <span class="o">=</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span><span class="p">(</span><span class="n">capfirst</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">))</span> <span class="k">return</span> <span class="n">ValidationError</span><span class="p">(</span> <span class="n">message</span><span class="o">=</span><span class="n">field</span><span class="o">.</span><span class="n">error_messages</span><span class="p">[</span><span class="s1">'unique'</span><span class="p">],</span> <span class="n">code</span><span class="o">=</span><span class="s1">'unique'</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="n">params</span><span class="p">,</span> <span class="p">)</span> <span class="c1"># unique_together</span> <span class="k">else</span><span class="p">:</span> <span class="n">field_labels</span> <span class="o">=</span> <span class="p">[</span><span class="n">capfirst</span><span class="p">(</span><span class="n">opts</span><span class="o">.</span><span class="n">get_field</span><span class="p">(</span><span class="n">f</span><span class="p">)</span><span class="o">.</span><span class="n">verbose_name</span><span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">unique_check</span><span class="p">]</span> <span class="n">params</span><span class="p">[</span><span class="s1">'field_labels'</span><span class="p">]</span> <span class="o">=</span> <span class="n">six</span><span class="o">.</span><span class="n">text_type</span><span class="p">(</span><span class="n">get_text_list</span><span class="p">(</span><span class="n">field_labels</span><span class="p">,</span> <span class="n">_</span><span class="p">(</span><span class="s1">'and'</span><span class="p">)))</span> <span class="k">return</span> <span class="n">ValidationError</span><span class="p">(</span> <span class="n">message</span><span class="o">=</span><span class="n">_</span><span class="p">(</span><span class="s2">"</span><span class="si">%(model_name)s</span><span class="s2"> with this </span><span class="si">%(field_labels)s</span><span class="s2"> already exists."</span><span class="p">),</span> <span class="n">code</span><span class="o">=</span><span class="s1">'unique_together'</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="n">params</span><span class="p">,</span> <span class="p">)</span> <div class="viewcode-block" id="Model.full_clean"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.full_clean">[docs]</a> <span class="k">def</span> <span class="nf">full_clean</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">exclude</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">validate_unique</span><span class="o">=</span><span class="kc">True</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Calls clean_fields, clean, and validate_unique, on the model,</span> <span class="sd"> and raises a ``ValidationError`` for any errors that occurred.</span> <span class="sd"> """</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">if</span> <span class="n">exclude</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">exclude</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">else</span><span class="p">:</span> <span class="n">exclude</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">exclude</span><span class="p">)</span> <span class="k">try</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">clean_fields</span><span class="p">(</span><span class="n">exclude</span><span class="o">=</span><span class="n">exclude</span><span class="p">)</span> <span class="k">except</span> <span class="n">ValidationError</span> <span class="k">as</span> <span class="n">e</span><span class="p">:</span> <span class="n">errors</span> <span class="o">=</span> <span class="n">e</span><span class="o">.</span><span class="n">update_error_dict</span><span class="p">(</span><span class="n">errors</span><span class="p">)</span> <span class="c1"># Form.clean() is run even if other validation fails, so do the</span> <span class="c1"># same with Model.clean() for consistency.</span> <span class="k">try</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">clean</span><span class="p">()</span> <span class="k">except</span> <span class="n">ValidationError</span> <span class="k">as</span> <span class="n">e</span><span class="p">:</span> <span class="n">errors</span> <span class="o">=</span> <span class="n">e</span><span class="o">.</span><span class="n">update_error_dict</span><span class="p">(</span><span class="n">errors</span><span class="p">)</span> <span class="c1"># Run unique checks, but only for fields that passed validation.</span> <span class="k">if</span> <span class="n">validate_unique</span><span class="p">:</span> <span class="k">for</span> <span class="n">name</span> <span class="ow">in</span> <span class="n">errors</span><span class="o">.</span><span class="n">keys</span><span class="p">():</span> <span class="k">if</span> <span class="n">name</span> <span class="o">!=</span> <span class="n">NON_FIELD_ERRORS</span> <span class="ow">and</span> <span class="n">name</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">exclude</span><span class="p">:</span> <span class="n">exclude</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">name</span><span class="p">)</span> <span class="k">try</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">validate_unique</span><span class="p">(</span><span class="n">exclude</span><span class="o">=</span><span class="n">exclude</span><span class="p">)</span> <span class="k">except</span> <span class="n">ValidationError</span> <span class="k">as</span> <span class="n">e</span><span class="p">:</span> <span class="n">errors</span> <span class="o">=</span> <span class="n">e</span><span class="o">.</span><span class="n">update_error_dict</span><span class="p">(</span><span class="n">errors</span><span class="p">)</span> <span class="k">if</span> <span class="n">errors</span><span class="p">:</span> <span class="k">raise</span> <span class="n">ValidationError</span><span class="p">(</span><span class="n">errors</span><span class="p">)</span></div> <div class="viewcode-block" id="Model.clean_fields"><a class="viewcode-back" href="../../../../ref/models/instances.html#django.db.models.Model.clean_fields">[docs]</a> <span class="k">def</span> <span class="nf">clean_fields</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">exclude</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Cleans all fields and raises a ValidationError containing a dict</span> <span class="sd"> of all validation errors if any occur.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="n">exclude</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">exclude</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">:</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="ow">in</span> <span class="n">exclude</span><span class="p">:</span> <span class="k">continue</span> <span class="c1"># Skip validation for empty fields with blank=True. The developer</span> <span class="c1"># is responsible for making sure they have a valid value.</span> <span class="n">raw_value</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">blank</span> <span class="ow">and</span> <span class="n">raw_value</span> <span class="ow">in</span> <span class="n">f</span><span class="o">.</span><span class="n">empty_values</span><span class="p">:</span> <span class="k">continue</span> <span class="k">try</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">clean</span><span class="p">(</span><span class="n">raw_value</span><span class="p">,</span> <span class="bp">self</span><span class="p">))</span> <span class="k">except</span> <span class="n">ValidationError</span> <span class="k">as</span> <span class="n">e</span><span class="p">:</span> <span class="n">errors</span><span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">]</span> <span class="o">=</span> <span class="n">e</span><span class="o">.</span><span class="n">error_list</span> <span class="k">if</span> <span class="n">errors</span><span class="p">:</span> <span class="k">raise</span> <span class="n">ValidationError</span><span class="p">(</span><span class="n">errors</span><span class="p">)</span></div> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">check</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_swappable</span><span class="p">())</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_model</span><span class="p">())</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_managers</span><span class="p">(</span><span class="o">**</span><span class="n">kwargs</span><span class="p">))</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">swapped</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_fields</span><span class="p">(</span><span class="o">**</span><span class="n">kwargs</span><span class="p">))</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_m2m_through_same_relationship</span><span class="p">())</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_long_column_names</span><span class="p">())</span> <span class="n">clash_errors</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_check_id_field</span><span class="p">()</span> <span class="o">+</span> <span class="n">cls</span><span class="o">.</span><span class="n">_check_field_name_clashes</span><span class="p">()</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">clash_errors</span><span class="p">)</span> <span class="c1"># If there are field name clashes, hide consequent column name</span> <span class="c1"># clashes.</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">clash_errors</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_column_name_clashes</span><span class="p">())</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_index_together</span><span class="p">())</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_unique_together</span><span class="p">())</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_ordering</span><span class="p">())</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_swappable</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">""" Check if the swapped model exists. """</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">if</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">swapped</span><span class="p">:</span> <span class="k">try</span><span class="p">:</span> <span class="n">apps</span><span class="o">.</span><span class="n">get_model</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">swapped</span><span class="p">)</span> <span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"'</span><span class="si">%s</span><span class="s2">' is not of the form 'app_label.app_name'."</span> <span class="o">%</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">swappable</span><span class="p">,</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E001'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">except</span> <span class="ne">LookupError</span><span class="p">:</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">model_name</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">swapped</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="s1">'.'</span><span class="p">)</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"'</span><span class="si">%s</span><span class="s2">' references '</span><span class="si">%s</span><span class="s2">.</span><span class="si">%s</span><span class="s2">', which has not been "</span> <span class="s2">"installed, or is abstract."</span> <span class="o">%</span> <span class="p">(</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">swappable</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">model_name</span> <span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E002'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_model</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">if</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">proxy</span><span class="p">:</span> <span class="k">if</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span> <span class="ow">or</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_many_to_many</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"Proxy model '</span><span class="si">%s</span><span class="s2">' contains model fields."</span> <span class="o">%</span> <span class="n">cls</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E017'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_managers</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">""" Perform all manager checks. """</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">__</span><span class="p">,</span> <span class="n">manager</span><span class="p">,</span> <span class="n">__</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">managers</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">manager</span><span class="o">.</span><span class="n">check</span><span class="p">(</span><span class="o">**</span><span class="n">kwargs</span><span class="p">))</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_fields</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">""" Perform all field checks. """</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">check</span><span class="p">(</span><span class="o">**</span><span class="n">kwargs</span><span class="p">))</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_many_to_many</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">check</span><span class="p">(</span><span class="n">from_model</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">))</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_m2m_through_same_relationship</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">""" Check if no relationship model is used by more than one m2m field.</span> <span class="sd"> """</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">seen_intermediary_signatures</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">fields</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_many_to_many</span> <span class="c1"># Skip when the target model wasn't found.</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">,</span> <span class="n">ModelBase</span><span class="p">))</span> <span class="c1"># Skip when the relationship model wasn't found.</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">through</span><span class="p">,</span> <span class="n">ModelBase</span><span class="p">))</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">:</span> <span class="n">signature</span> <span class="o">=</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">to</span><span class="p">,</span> <span class="n">cls</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">through</span><span class="p">)</span> <span class="k">if</span> <span class="n">signature</span> <span class="ow">in</span> <span class="n">seen_intermediary_signatures</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"The model has two many-to-many relations through "</span> <span class="s2">"the intermediate model '</span><span class="si">%s</span><span class="s2">.</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="p">(</span> <span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">through</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">app_label</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">through</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span> <span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E003'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">seen_intermediary_signatures</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">signature</span><span class="p">)</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_id_field</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">""" Check if `id` field is a primary key. """</span> <span class="n">fields</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="s1">'id'</span> <span class="ow">and</span> <span class="n">f</span> <span class="o">!=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="p">)</span> <span class="c1"># fields is empty or consists of the invalid "id" field</span> <span class="k">if</span> <span class="n">fields</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">fields</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span><span class="o">.</span><span class="n">primary_key</span> <span class="ow">and</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="s1">'id'</span><span class="p">:</span> <span class="k">return</span> <span class="p">[</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"'id' can only be used as a field name if the field also "</span> <span class="s2">"sets 'primary_key=True'."</span><span class="p">,</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E004'</span><span class="p">,</span> <span class="p">)</span> <span class="p">]</span> <span class="k">else</span><span class="p">:</span> <span class="k">return</span> <span class="p">[]</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_field_name_clashes</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">""" Ref #17673. """</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">used_fields</span> <span class="o">=</span> <span class="p">{}</span> <span class="c1"># name or attname -> field</span> <span class="c1"># Check that multi-inheritance doesn't cause field name shadowing.</span> <span class="k">for</span> <span class="n">parent</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_parent_list</span><span class="p">():</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">parent</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">:</span> <span class="n">clash</span> <span class="o">=</span> <span class="n">used_fields</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">)</span> <span class="ow">or</span> <span class="n">used_fields</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="ow">or</span> <span class="kc">None</span> <span class="k">if</span> <span class="n">clash</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"The field '</span><span class="si">%s</span><span class="s2">' from parent model "</span> <span class="s2">"'</span><span class="si">%s</span><span class="s2">' clashes with the field '</span><span class="si">%s</span><span class="s2">' "</span> <span class="s2">"from parent model '</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="p">(</span> <span class="n">clash</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">clash</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span> <span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E005'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="n">used_fields</span><span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">]</span> <span class="o">=</span> <span class="n">f</span> <span class="n">used_fields</span><span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">]</span> <span class="o">=</span> <span class="n">f</span> <span class="c1"># Check that fields defined in the model don't clash with fields from</span> <span class="c1"># parents.</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">:</span> <span class="n">clash</span> <span class="o">=</span> <span class="n">used_fields</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">)</span> <span class="ow">or</span> <span class="n">used_fields</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="ow">or</span> <span class="kc">None</span> <span class="c1"># Note that we may detect clash between user-defined non-unique</span> <span class="c1"># field "id" and automatically added unique field "id", both</span> <span class="c1"># defined at the same model. This special case is considered in</span> <span class="c1"># _check_id_field and here we ignore it.</span> <span class="n">id_conflict</span> <span class="o">=</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="s2">"id"</span> <span class="ow">and</span> <span class="n">clash</span> <span class="ow">and</span> <span class="n">clash</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="s2">"id"</span> <span class="ow">and</span> <span class="n">clash</span><span class="o">.</span><span class="n">model</span> <span class="o">==</span> <span class="n">cls</span><span class="p">)</span> <span class="k">if</span> <span class="n">clash</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">id_conflict</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"The field '</span><span class="si">%s</span><span class="s2">' clashes with the field '</span><span class="si">%s</span><span class="s2">' "</span> <span class="s2">"from model '</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="p">(</span> <span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">clash</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">clash</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span> <span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">f</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E006'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="n">used_fields</span><span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">]</span> <span class="o">=</span> <span class="n">f</span> <span class="n">used_fields</span><span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">]</span> <span class="o">=</span> <span class="n">f</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_column_name_clashes</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="c1"># Store a list of column names which have already been used by other fields.</span> <span class="n">used_column_names</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">:</span> <span class="n">_</span><span class="p">,</span> <span class="n">column_name</span> <span class="o">=</span> <span class="n">f</span><span class="o">.</span><span class="n">get_attname_column</span><span class="p">()</span> <span class="c1"># Ensure the column name is not already in use.</span> <span class="k">if</span> <span class="n">column_name</span> <span class="ow">and</span> <span class="n">column_name</span> <span class="ow">in</span> <span class="n">used_column_names</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"Field '</span><span class="si">%s</span><span class="s2">' has column name '</span><span class="si">%s</span><span class="s2">' that is used by "</span> <span class="s2">"another field."</span> <span class="o">%</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">column_name</span><span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="s2">"Specify a 'db_column' for the field."</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E007'</span> <span class="p">)</span> <span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">used_column_names</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">column_name</span><span class="p">)</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_index_together</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">""" Check the value of "index_together" option. """</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">index_together</span><span class="p">,</span> <span class="p">(</span><span class="nb">tuple</span><span class="p">,</span> <span class="nb">list</span><span class="p">)):</span> <span class="k">return</span> <span class="p">[</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"'index_together' must be a list or tuple."</span><span class="p">,</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E008'</span><span class="p">,</span> <span class="p">)</span> <span class="p">]</span> <span class="k">elif</span> <span class="nb">any</span><span class="p">(</span><span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">fields</span><span class="p">,</span> <span class="p">(</span><span class="nb">tuple</span><span class="p">,</span> <span class="nb">list</span><span class="p">))</span> <span class="k">for</span> <span class="n">fields</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">index_together</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"All 'index_together' elements must be lists or tuples."</span><span class="p">,</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E009'</span><span class="p">,</span> <span class="p">)</span> <span class="p">]</span> <span class="k">else</span><span class="p">:</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">fields</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">index_together</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_local_fields</span><span class="p">(</span><span class="n">fields</span><span class="p">,</span> <span class="s2">"index_together"</span><span class="p">))</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_unique_together</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">""" Check the value of "unique_together" option. """</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">unique_together</span><span class="p">,</span> <span class="p">(</span><span class="nb">tuple</span><span class="p">,</span> <span class="nb">list</span><span class="p">)):</span> <span class="k">return</span> <span class="p">[</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"'unique_together' must be a list or tuple."</span><span class="p">,</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E010'</span><span class="p">,</span> <span class="p">)</span> <span class="p">]</span> <span class="k">elif</span> <span class="nb">any</span><span class="p">(</span><span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">fields</span><span class="p">,</span> <span class="p">(</span><span class="nb">tuple</span><span class="p">,</span> <span class="nb">list</span><span class="p">))</span> <span class="k">for</span> <span class="n">fields</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">unique_together</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"All 'unique_together' elements must be lists or tuples."</span><span class="p">,</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E011'</span><span class="p">,</span> <span class="p">)</span> <span class="p">]</span> <span class="k">else</span><span class="p">:</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">fields</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">unique_together</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_check_local_fields</span><span class="p">(</span><span class="n">fields</span><span class="p">,</span> <span class="s2">"unique_together"</span><span class="p">))</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_local_fields</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">option</span><span class="p">):</span> <span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">models</span> <span class="c1"># In order to avoid hitting the relation tree prematurely, we use our</span> <span class="c1"># own fields_map instead of using get_field()</span> <span class="n">forward_fields_map</span> <span class="o">=</span> <span class="p">{</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">:</span> <span class="n">field</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">_get_fields</span><span class="p">(</span><span class="n">reverse</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="p">}</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">field_name</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">:</span> <span class="k">try</span><span class="p">:</span> <span class="n">field</span> <span class="o">=</span> <span class="n">forward_fields_map</span><span class="p">[</span><span class="n">field_name</span><span class="p">]</span> <span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"'</span><span class="si">%s</span><span class="s2">' refers to the non-existent field '</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="p">(</span> <span class="n">option</span><span class="p">,</span> <span class="n">field_name</span><span class="p">,</span> <span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E012'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="p">,</span> <span class="n">models</span><span class="o">.</span><span class="n">ManyToManyRel</span><span class="p">):</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"'</span><span class="si">%s</span><span class="s2">' refers to a ManyToManyField '</span><span class="si">%s</span><span class="s2">', but "</span> <span class="s2">"ManyToManyFields are not permitted in '</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="p">(</span> <span class="n">option</span><span class="p">,</span> <span class="n">field_name</span><span class="p">,</span> <span class="n">option</span><span class="p">,</span> <span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E013'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">elif</span> <span class="n">field</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="p">(</span><span class="s2">"'</span><span class="si">%s</span><span class="s2">' refers to field '</span><span class="si">%s</span><span class="s2">' which is not local "</span> <span class="s2">"to model '</span><span class="si">%s</span><span class="s2">'."</span><span class="p">)</span> <span class="o">%</span> <span class="p">(</span> <span class="n">option</span><span class="p">,</span> <span class="n">field_name</span><span class="p">,</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span> <span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="p">(</span><span class="s2">"This issue may be caused by multi-table "</span> <span class="s2">"inheritance."</span><span class="p">),</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E016'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_ordering</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">""" Check "ordering" option -- is it a list of strings and do all fields</span> <span class="sd"> exist? """</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">ordering</span><span class="p">:</span> <span class="k">return</span> <span class="p">[]</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">ordering</span><span class="p">,</span> <span class="p">(</span><span class="nb">list</span><span class="p">,</span> <span class="nb">tuple</span><span class="p">)):</span> <span class="k">return</span> <span class="p">[</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="p">(</span><span class="s2">"'ordering' must be a tuple or list "</span> <span class="s2">"(even if you want to order by only one field)."</span><span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E014'</span><span class="p">,</span> <span class="p">)</span> <span class="p">]</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">fields</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">ordering</span> <span class="c1"># Skip '?' fields.</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="n">f</span> <span class="o">!=</span> <span class="s1">'?'</span><span class="p">)</span> <span class="c1"># Convert "-field" to "field".</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">((</span><span class="n">f</span><span class="p">[</span><span class="mi">1</span><span class="p">:]</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="s1">'-'</span><span class="p">)</span> <span class="k">else</span> <span class="n">f</span><span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">)</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="n">f</span> <span class="o">!=</span> <span class="s1">'_order'</span> <span class="ow">or</span> <span class="ow">not</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">order_with_respect_to</span><span class="p">)</span> <span class="c1"># Skip ordering in the format field1__field2 (FIXME: checking</span> <span class="c1"># this format would be nice, but it's a little fiddly).</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">(</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="s1">'__'</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">f</span><span class="p">)</span> <span class="c1"># Skip ordering on pk. This is always a valid order_by field</span> <span class="c1"># but is an alias and therefore won't be found by opts.get_field.</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">{</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="n">f</span> <span class="o">!=</span> <span class="s1">'pk'</span><span class="p">}</span> <span class="c1"># Check for invalid or non-existent fields in ordering.</span> <span class="n">invalid_fields</span> <span class="o">=</span> <span class="p">[]</span> <span class="c1"># Any field name that is not present in field_names does not exist.</span> <span class="c1"># Also, ordering by m2m fields is not allowed.</span> <span class="n">opts</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span> <span class="n">valid_fields</span> <span class="o">=</span> <span class="nb">set</span><span class="p">(</span><span class="n">chain</span><span class="o">.</span><span class="n">from_iterable</span><span class="p">(</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">auto_created</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">f</span><span class="o">.</span><span class="n">concrete</span><span class="p">)</span> <span class="k">else</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">field</span><span class="o">.</span><span class="n">related_query_name</span><span class="p">(),)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">chain</span><span class="p">(</span><span class="n">opts</span><span class="o">.</span><span class="n">fields</span><span class="p">,</span> <span class="n">opts</span><span class="o">.</span><span class="n">related_objects</span><span class="p">)</span> <span class="p">))</span> <span class="n">invalid_fields</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">fields</span> <span class="o">-</span> <span class="n">valid_fields</span><span class="p">)</span> <span class="k">for</span> <span class="n">invalid_field</span> <span class="ow">in</span> <span class="n">invalid_fields</span><span class="p">:</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s2">"'ordering' refers to the non-existent field '</span><span class="si">%s</span><span class="s2">'."</span> <span class="o">%</span> <span class="n">invalid_field</span><span class="p">,</span> <span class="n">hint</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E015'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">return</span> <span class="n">errors</span> <span class="nd">@classmethod</span> <span class="k">def</span> <span class="nf">_check_long_column_names</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Check that any auto-generated column names are shorter than the limits</span> <span class="sd"> for each database in which the model will be created.</span> <span class="sd"> """</span> <span class="n">errors</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">allowed_len</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">db_alias</span> <span class="o">=</span> <span class="kc">None</span> <span class="c1"># Find the minimum max allowed length among all specified db_aliases.</span> <span class="k">for</span> <span class="n">db</span> <span class="ow">in</span> <span class="n">settings</span><span class="o">.</span><span class="n">DATABASES</span><span class="o">.</span><span class="n">keys</span><span class="p">():</span> <span class="c1"># skip databases where the model won't be created</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">router</span><span class="o">.</span><span class="n">allow_migrate_model</span><span class="p">(</span><span class="n">db</span><span class="p">,</span> <span class="n">cls</span><span class="p">):</span> <span class="k">continue</span> <span class="n">connection</span> <span class="o">=</span> <span class="n">connections</span><span class="p">[</span><span class="n">db</span><span class="p">]</span> <span class="n">max_name_length</span> <span class="o">=</span> <span class="n">connection</span><span class="o">.</span><span class="n">ops</span><span class="o">.</span><span class="n">max_name_length</span><span class="p">()</span> <span class="k">if</span> <span class="n">max_name_length</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">connection</span><span class="o">.</span><span class="n">features</span><span class="o">.</span><span class="n">truncates_names</span><span class="p">:</span> <span class="k">continue</span> <span class="k">else</span><span class="p">:</span> <span class="k">if</span> <span class="n">allowed_len</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">allowed_len</span> <span class="o">=</span> <span class="n">max_name_length</span> <span class="n">db_alias</span> <span class="o">=</span> <span class="n">db</span> <span class="k">elif</span> <span class="n">max_name_length</span> <span class="o"><</span> <span class="n">allowed_len</span><span class="p">:</span> <span class="n">allowed_len</span> <span class="o">=</span> <span class="n">max_name_length</span> <span class="n">db_alias</span> <span class="o">=</span> <span class="n">db</span> <span class="k">if</span> <span class="n">allowed_len</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">return</span> <span class="n">errors</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">:</span> <span class="n">_</span><span class="p">,</span> <span class="n">column_name</span> <span class="o">=</span> <span class="n">f</span><span class="o">.</span><span class="n">get_attname_column</span><span class="p">()</span> <span class="c1"># Check if auto-generated name for the field is too long</span> <span class="c1"># for the database.</span> <span class="k">if</span> <span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">db_column</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">and</span> <span class="n">column_name</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="n">column_name</span><span class="p">)</span> <span class="o">></span> <span class="n">allowed_len</span><span class="p">):</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s1">'Autogenerated column name too long for field "</span><span class="si">%s</span><span class="s1">". '</span> <span class="s1">'Maximum length is "</span><span class="si">%s</span><span class="s1">" for database "</span><span class="si">%s</span><span class="s1">".'</span> <span class="o">%</span> <span class="p">(</span><span class="n">column_name</span><span class="p">,</span> <span class="n">allowed_len</span><span class="p">,</span> <span class="n">db_alias</span><span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="s2">"Set the column name manually using 'db_column'."</span><span class="p">,</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E018'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_many_to_many</span><span class="p">:</span> <span class="c1"># Check if auto-generated name for the M2M field is too long</span> <span class="c1"># for the database.</span> <span class="k">for</span> <span class="n">m2m</span> <span class="ow">in</span> <span class="n">f</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">through</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_fields</span><span class="p">:</span> <span class="n">_</span><span class="p">,</span> <span class="n">rel_name</span> <span class="o">=</span> <span class="n">m2m</span><span class="o">.</span><span class="n">get_attname_column</span><span class="p">()</span> <span class="k">if</span> <span class="p">(</span><span class="n">m2m</span><span class="o">.</span><span class="n">db_column</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">and</span> <span class="n">rel_name</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="n">rel_name</span><span class="p">)</span> <span class="o">></span> <span class="n">allowed_len</span><span class="p">):</span> <span class="n">errors</span><span class="o">.</span><span class="n">append</span><span class="p">(</span> <span class="n">checks</span><span class="o">.</span><span class="n">Error</span><span class="p">(</span> <span class="s1">'Autogenerated column name too long for M2M field '</span> <span class="s1">'"</span><span class="si">%s</span><span class="s1">". Maximum length is "</span><span class="si">%s</span><span class="s1">" for database "</span><span class="si">%s</span><span class="s1">".'</span> <span class="o">%</span> <span class="p">(</span><span class="n">rel_name</span><span class="p">,</span> <span class="n">allowed_len</span><span class="p">,</span> <span class="n">db_alias</span><span class="p">),</span> <span class="n">hint</span><span class="o">=</span><span class="p">(</span><span class="s2">"Use 'through' to create a separate model "</span> <span class="s2">"for M2M and then set column_name using "</span> <span class="s2">"'db_column'."</span><span class="p">),</span> <span class="n">obj</span><span class="o">=</span><span class="n">cls</span><span class="p">,</span> <span class="nb">id</span><span class="o">=</span><span class="s1">'models.E019'</span><span class="p">,</span> <span class="p">)</span> <span class="p">)</span> <span class="k">return</span> <span class="n">errors</span></div> <span class="c1">############################################</span> <span class="c1"># HELPER FUNCTIONS (CURRIED MODEL METHODS) #</span> <span class="c1">############################################</span> <span class="c1"># ORDERING METHODS #########################</span> <span class="k">def</span> <span class="nf">method_set_order</span><span class="p">(</span><span class="n">ordered_obj</span><span class="p">,</span> <span class="bp">self</span><span class="p">,</span> <span class="n">id_list</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="k">if</span> <span class="n">using</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">using</span> <span class="o">=</span> <span class="n">DEFAULT_DB_ALIAS</span> <span class="n">order_wrt</span> <span class="o">=</span> <span class="n">ordered_obj</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">order_with_respect_to</span> <span class="n">filter_args</span> <span class="o">=</span> <span class="n">order_wrt</span><span class="o">.</span><span class="n">get_forward_related_filter</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="c1"># FIXME: It would be nice if there was an "update many" version of update</span> <span class="c1"># for situations like this.</span> <span class="k">with</span> <span class="n">transaction</span><span class="o">.</span><span class="n">atomic</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">,</span> <span class="n">savepoint</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="k">for</span> <span class="n">i</span><span class="p">,</span> <span class="n">j</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="n">id_list</span><span class="p">):</span> <span class="n">ordered_obj</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">pk</span><span class="o">=</span><span class="n">j</span><span class="p">,</span> <span class="o">**</span><span class="n">filter_args</span><span class="p">)</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">_order</span><span class="o">=</span><span class="n">i</span><span class="p">)</span> <span class="k">def</span> <span class="nf">method_get_order</span><span class="p">(</span><span class="n">ordered_obj</span><span class="p">,</span> <span class="bp">self</span><span class="p">):</span> <span class="n">rel_val</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">ordered_obj</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">order_with_respect_to</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">field_name</span><span class="p">)</span> <span class="n">order_name</span> <span class="o">=</span> <span class="n">ordered_obj</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">order_with_respect_to</span><span class="o">.</span><span class="n">name</span> <span class="n">pk_name</span> <span class="o">=</span> <span class="n">ordered_obj</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">name</span> <span class="k">return</span> <span class="p">[</span><span class="n">r</span><span class="p">[</span><span class="n">pk_name</span><span class="p">]</span> <span class="k">for</span> <span class="n">r</span> <span class="ow">in</span> <span class="n">ordered_obj</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o">**</span><span class="p">{</span><span class="n">order_name</span><span class="p">:</span> <span class="n">rel_val</span><span class="p">})</span><span class="o">.</span><span class="n">values</span><span class="p">(</span><span class="n">pk_name</span><span class="p">)]</span> <span class="c1">########</span> <span class="c1"># MISC #</span> <span class="c1">########</span> <span class="k">def</span> <span class="nf">simple_class_factory</span><span class="p">(</span><span class="n">model</span><span class="p">,</span> <span class="n">attrs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Needed for dynamic classes.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="n">model</span> <span class="k">def</span> <span class="nf">model_unpickle</span><span class="p">(</span><span class="n">model_id</span><span class="p">,</span> <span class="n">attrs</span><span class="p">,</span> <span class="n">factory</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Used to unpickle Model subclasses with deferred fields.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">model_id</span><span class="p">,</span> <span class="nb">tuple</span><span class="p">):</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">apps</span><span class="o">.</span><span class="n">ready</span><span class="p">:</span> <span class="n">apps</span><span class="o">.</span><span class="n">populate</span><span class="p">(</span><span class="n">settings</span><span class="o">.</span><span class="n">INSTALLED_APPS</span><span class="p">)</span> <span class="n">model</span> <span class="o">=</span> <span class="n">apps</span><span class="o">.</span><span class="n">get_model</span><span class="p">(</span><span class="o">*</span><span class="n">model_id</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># Backwards compat - the model was cached directly in earlier versions.</span> <span class="n">model</span> <span class="o">=</span> <span class="n">model_id</span> <span class="n">cls</span> <span class="o">=</span> <span class="n">factory</span><span class="p">(</span><span class="n">model</span><span class="p">,</span> <span class="n">attrs</span><span class="p">)</span> <span class="k">return</span> <span class="n">cls</span><span class="o">.</span><span class="n">__new__</span><span class="p">(</span><span class="n">cls</span><span class="p">)</span> <span class="n">model_unpickle</span><span class="o">.</span><span class="n">__safe_for_unpickle__</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">unpickle_inner_exception</span><span class="p">(</span><span class="n">klass</span><span class="p">,</span> <span class="n">exception_name</span><span class="p">):</span> <span class="c1"># Get the exception class from the class it is attached to:</span> <span class="n">exception</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">klass</span><span class="p">,</span> <span class="n">exception_name</span><span class="p">)</span> <span class="k">return</span> <span class="n">exception</span><span class="o">.</span><span class="n">__new__</span><span class="p">(</span><span class="n">exception</span><span class="p">)</span> </pre></div> </div> </div> </div> <div class="yui-b" id="sidebar"> <div class="sphinxsidebar" role="navigation" aria-label="main navigation"> <div class="sphinxsidebarwrapper"> <h3>Browse</h3> <ul> </ul> <h3>You are here:</h3> <ul> <li> <a href="../../../../index.html">Django 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