<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" lang=""> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>django.db.migrations.operations.special — Django 1.8.19 documentation</title> <link rel="stylesheet" href="../../../../../_static/default.css" type="text/css" /> <link rel="stylesheet" href="../../../../../_static/pygments.css" type="text/css" /> <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT: '../../../../../', VERSION: '1.8.19', COLLAPSE_INDEX: false, FILE_SUFFIX: '.html', HAS_SOURCE: true }; </script> <script type="text/javascript" src="../../../../../_static/jquery.js"></script> <script type="text/javascript" src="../../../../../_static/underscore.js"></script> <script type="text/javascript" src="../../../../../_static/doctools.js"></script> <link rel="index" title="Index" href="../../../../../genindex.html" /> <link rel="search" title="Search" href="../../../../../search.html" /> <link rel="top" title="Django 1.8.19 documentation" href="../../../../../contents.html" /> <link rel="up" title="django" href="../../../../django.html" /> <script type="text/javascript" src="../../../../../templatebuiltins.js"></script> <script type="text/javascript"> (function($) { if (!django_template_builtins) { // templatebuiltins.js missing, do nothing. return; } $(document).ready(function() { // Hyperlink Django template tags and filters var base = "../../../../../ref/templates/builtins.html"; if (base == "#") { // Special case for builtins.html itself base = ""; } // Tags are keywords, class '.k' $("div.highlight\\-html\\+django span.k").each(function(i, elem) { var tagname = $(elem).text(); if ($.inArray(tagname, django_template_builtins.ttags) != -1) { var fragment = tagname.replace(/_/, '-'); $(elem).html("<a href='" + base + "#" + fragment + "'>" + tagname + "</a>"); } }); // Filters are functions, class '.nf' $("div.highlight\\-html\\+django span.nf").each(function(i, elem) { var filtername = $(elem).text(); if ($.inArray(filtername, django_template_builtins.tfilters) != -1) { var fragment = filtername.replace(/_/, '-'); $(elem).html("<a href='" + base + "#" + fragment + "'>" + filtername + "</a>"); } }); }); })(jQuery); </script> </head> <body role="document"> <div class="document"> <div id="custom-doc" class="yui-t6"> <div id="hd"> <h1><a href="../../../../../index.html">Django 1.8.19 documentation</a></h1> <div id="global-nav"> <a title="Home page" href="../../../../../index.html">Home</a> | <a title="Table of contents" href="../../../../../contents.html">Table of contents</a> | <a title="Global index" href="../../../../../genindex.html">Index</a> | <a title="Module index" href="../../../../../py-modindex.html">Modules</a> </div> <div class="nav"> <a href="../../../../index.html" title="Module code" accesskey="U">up</a></div> </div> <div id="bd"> <div id="yui-main"> <div class="yui-b"> <div class="yui-g" id="_modules-django-db-migrations-operations-special"> <h1>Source code for django.db.migrations.operations.special</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">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">router</span> <span class="kn">from</span> <span class="nn">.base</span> <span class="k">import</span> <span class="n">Operation</span> <div class="viewcode-block" id="SeparateDatabaseAndState"><a class="viewcode-back" href="../../../../../ref/migration-operations.html#django.db.migrations.operations.SeparateDatabaseAndState">[docs]</a><span class="k">class</span> <span class="nc">SeparateDatabaseAndState</span><span class="p">(</span><span class="n">Operation</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Takes two lists of operations - ones that will be used for the database,</span> <span class="sd"> and ones that will be used for the state change. This allows operations</span> <span class="sd"> that don't support state change to have it applied, or have operations</span> <span class="sd"> that affect the state or not the database, or so on.</span> <span class="sd"> """</span> <span class="n">serialization_expand_args</span> <span class="o">=</span> <span class="p">[</span><span class="s1">'database_operations'</span><span class="p">,</span> <span class="s1">'state_operations'</span><span class="p">]</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">database_operations</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">state_operations</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">database_operations</span> <span class="o">=</span> <span class="n">database_operations</span> <span class="ow">or</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">state_operations</span> <span class="o">=</span> <span class="n">state_operations</span> <span class="ow">or</span> <span class="p">[]</span> <span class="k">def</span> <span class="nf">deconstruct</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">kwargs</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">database_operations</span><span class="p">:</span> <span class="n">kwargs</span><span class="p">[</span><span class="s1">'database_operations'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">database_operations</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">state_operations</span><span class="p">:</span> <span class="n">kwargs</span><span class="p">[</span><span class="s1">'state_operations'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">state_operations</span> <span class="k">return</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="p">[],</span> <span class="n">kwargs</span> <span class="p">)</span> <span class="k">def</span> <span class="nf">state_forwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">state</span><span class="p">):</span> <span class="k">for</span> <span class="n">state_operation</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">state_operations</span><span class="p">:</span> <span class="n">state_operation</span><span class="o">.</span><span class="n">state_forwards</span><span class="p">(</span><span class="n">app_label</span><span class="p">,</span> <span class="n">state</span><span class="p">)</span> <span class="k">def</span> <span class="nf">database_forwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">from_state</span><span class="p">,</span> <span class="n">to_state</span><span class="p">):</span> <span class="c1"># We calculate state separately in here since our state functions aren't useful</span> <span class="k">for</span> <span class="n">database_operation</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">database_operations</span><span class="p">:</span> <span class="n">to_state</span> <span class="o">=</span> <span class="n">from_state</span><span class="o">.</span><span class="n">clone</span><span class="p">()</span> <span class="n">database_operation</span><span class="o">.</span><span class="n">state_forwards</span><span class="p">(</span><span class="n">app_label</span><span class="p">,</span> <span class="n">to_state</span><span class="p">)</span> <span class="n">database_operation</span><span class="o">.</span><span class="n">database_forwards</span><span class="p">(</span><span class="n">app_label</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">from_state</span><span class="p">,</span> <span class="n">to_state</span><span class="p">)</span> <span class="n">from_state</span> <span class="o">=</span> <span class="n">to_state</span> <span class="k">def</span> <span class="nf">database_backwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">from_state</span><span class="p">,</span> <span class="n">to_state</span><span class="p">):</span> <span class="c1"># We calculate state separately in here since our state functions aren't useful</span> <span class="n">base_state</span> <span class="o">=</span> <span class="n">to_state</span> <span class="k">for</span> <span class="n">pos</span><span class="p">,</span> <span class="n">database_operation</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="nb">reversed</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">database_operations</span><span class="p">)):</span> <span class="n">to_state</span> <span class="o">=</span> <span class="n">base_state</span><span class="o">.</span><span class="n">clone</span><span class="p">()</span> <span class="k">for</span> <span class="n">dbop</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">database_operations</span><span class="p">[:</span><span class="o">-</span><span class="p">(</span><span class="n">pos</span> <span class="o">+</span> <span class="mi">1</span><span class="p">)]:</span> <span class="n">dbop</span><span class="o">.</span><span class="n">state_forwards</span><span class="p">(</span><span class="n">app_label</span><span class="p">,</span> <span class="n">to_state</span><span class="p">)</span> <span class="n">from_state</span> <span class="o">=</span> <span class="n">to_state</span><span class="o">.</span><span class="n">clone</span><span class="p">()</span> <span class="n">database_operation</span><span class="o">.</span><span class="n">state_forwards</span><span class="p">(</span><span class="n">app_label</span><span class="p">,</span> <span class="n">from_state</span><span class="p">)</span> <span class="n">database_operation</span><span class="o">.</span><span class="n">database_backwards</span><span class="p">(</span><span class="n">app_label</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">from_state</span><span class="p">,</span> <span class="n">to_state</span><span class="p">)</span> <span class="k">def</span> <span class="nf">describe</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="s2">"Custom state/database change combination"</span></div> <div class="viewcode-block" id="RunSQL"><a class="viewcode-back" href="../../../../../ref/migration-operations.html#django.db.migrations.operations.RunSQL">[docs]</a><span class="k">class</span> <span class="nc">RunSQL</span><span class="p">(</span><span class="n">Operation</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Runs some raw SQL. A reverse SQL statement may be provided.</span> <span class="sd"> Also accepts a list of operations that represent the state change effected</span> <span class="sd"> by this SQL change, in case it's custom column/table creation/deletion.</span> <span class="sd"> """</span> <span class="n">noop</span> <span class="o">=</span> <span class="s1">''</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">sql</span><span class="p">,</span> <span class="n">reverse_sql</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">state_operations</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">hints</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">sql</span> <span class="o">=</span> <span class="n">sql</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_sql</span> <span class="o">=</span> <span class="n">reverse_sql</span> <span class="bp">self</span><span class="o">.</span><span class="n">state_operations</span> <span class="o">=</span> <span class="n">state_operations</span> <span class="ow">or</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">hints</span> <span class="o">=</span> <span class="n">hints</span> <span class="ow">or</span> <span class="p">{}</span> <span class="k">def</span> <span class="nf">deconstruct</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">kwargs</span> <span class="o">=</span> <span class="p">{</span> <span class="s1">'sql'</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">sql</span><span class="p">,</span> <span class="p">}</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_sql</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="n">kwargs</span><span class="p">[</span><span class="s1">'reverse_sql'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_sql</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">state_operations</span><span class="p">:</span> <span class="n">kwargs</span><span class="p">[</span><span class="s1">'state_operations'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">state_operations</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">hints</span><span class="p">:</span> <span class="n">kwargs</span><span class="p">[</span><span class="s1">'hints'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">hints</span> <span class="k">return</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="p">[],</span> <span class="n">kwargs</span> <span class="p">)</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">reversible</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_sql</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="k">def</span> <span class="nf">state_forwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">state</span><span class="p">):</span> <span class="k">for</span> <span class="n">state_operation</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">state_operations</span><span class="p">:</span> <span class="n">state_operation</span><span class="o">.</span><span class="n">state_forwards</span><span class="p">(</span><span class="n">app_label</span><span class="p">,</span> <span class="n">state</span><span class="p">)</span> <span class="k">def</span> <span class="nf">database_forwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">from_state</span><span class="p">,</span> <span class="n">to_state</span><span class="p">):</span> <span class="k">if</span> <span class="n">router</span><span class="o">.</span><span class="n">allow_migrate</span><span class="p">(</span><span class="n">schema_editor</span><span class="o">.</span><span class="n">connection</span><span class="o">.</span><span class="n">alias</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">hints</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_run_sql</span><span class="p">(</span><span class="n">schema_editor</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">sql</span><span class="p">)</span> <span class="k">def</span> <span class="nf">database_backwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">from_state</span><span class="p">,</span> <span class="n">to_state</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_sql</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">NotImplementedError</span><span class="p">(</span><span class="s2">"You cannot reverse this operation"</span><span class="p">)</span> <span class="k">if</span> <span class="n">router</span><span class="o">.</span><span class="n">allow_migrate</span><span class="p">(</span><span class="n">schema_editor</span><span class="o">.</span><span class="n">connection</span><span class="o">.</span><span class="n">alias</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">hints</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_run_sql</span><span class="p">(</span><span class="n">schema_editor</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_sql</span><span class="p">)</span> <span class="k">def</span> <span class="nf">describe</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="s2">"Raw SQL operation"</span> <span class="k">def</span> <span class="nf">_run_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">sqls</span><span class="p">):</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">sqls</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">for</span> <span class="n">sql</span> <span class="ow">in</span> <span class="n">sqls</span><span class="p">:</span> <span class="n">params</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">sql</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="n">elements</span> <span class="o">=</span> <span class="nb">len</span><span class="p">(</span><span class="n">sql</span><span class="p">)</span> <span class="k">if</span> <span class="n">elements</span> <span class="o">==</span> <span class="mi">2</span><span class="p">:</span> <span class="n">sql</span><span class="p">,</span> <span class="n">params</span> <span class="o">=</span> <span class="n">sql</span> <span class="k">else</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"Expected a 2-tuple but got </span><span class="si">%d</span><span class="s2">"</span> <span class="o">%</span> <span class="n">elements</span><span class="p">)</span> <span class="n">schema_editor</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">sql</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="k">elif</span> <span class="n">sqls</span> <span class="o">!=</span> <span class="n">RunSQL</span><span class="o">.</span><span class="n">noop</span><span class="p">:</span> <span class="n">statements</span> <span class="o">=</span> <span class="n">schema_editor</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">prepare_sql_script</span><span class="p">(</span><span class="n">sqls</span><span class="p">)</span> <span class="k">for</span> <span class="n">statement</span> <span class="ow">in</span> <span class="n">statements</span><span class="p">:</span> <span class="n">schema_editor</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="n">statement</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="kc">None</span><span class="p">)</span></div> <div class="viewcode-block" id="RunPython"><a class="viewcode-back" href="../../../../../ref/migration-operations.html#django.db.migrations.operations.RunPython">[docs]</a><span class="k">class</span> <span class="nc">RunPython</span><span class="p">(</span><span class="n">Operation</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Runs Python code in a context suitable for doing versioned ORM operations.</span> <span class="sd"> """</span> <span class="n">reduces_to_sql</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="n">code</span><span class="p">,</span> <span class="n">reverse_code</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">atomic</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">hints</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">atomic</span> <span class="o">=</span> <span class="n">atomic</span> <span class="c1"># Forwards code</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">callable</span><span class="p">(</span><span class="n">code</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"RunPython must be supplied with a callable"</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">code</span> <span class="o">=</span> <span class="n">code</span> <span class="c1"># Reverse code</span> <span class="k">if</span> <span class="n">reverse_code</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_code</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">else</span><span class="p">:</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">callable</span><span class="p">(</span><span class="n">reverse_code</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"RunPython must be supplied with callable arguments"</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_code</span> <span class="o">=</span> <span class="n">reverse_code</span> <span class="bp">self</span><span class="o">.</span><span class="n">hints</span> <span class="o">=</span> <span class="n">hints</span> <span class="ow">or</span> <span class="p">{}</span> <span class="k">def</span> <span class="nf">deconstruct</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">kwargs</span> <span class="o">=</span> <span class="p">{</span> <span class="s1">'code'</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">code</span><span class="p">,</span> <span class="p">}</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_code</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="n">kwargs</span><span class="p">[</span><span class="s1">'reverse_code'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_code</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">atomic</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">True</span><span class="p">:</span> <span class="n">kwargs</span><span class="p">[</span><span class="s1">'atomic'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">atomic</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">hints</span><span class="p">:</span> <span class="n">kwargs</span><span class="p">[</span><span class="s1">'hints'</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">hints</span> <span class="k">return</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="p">[],</span> <span class="n">kwargs</span> <span class="p">)</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">reversible</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_code</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="k">def</span> <span class="nf">state_forwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">state</span><span class="p">):</span> <span class="c1"># RunPython objects have no state effect. To add some, combine this</span> <span class="c1"># with SeparateDatabaseAndState.</span> <span class="k">pass</span> <span class="k">def</span> <span class="nf">database_forwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">from_state</span><span class="p">,</span> <span class="n">to_state</span><span class="p">):</span> <span class="k">if</span> <span class="n">router</span><span class="o">.</span><span class="n">allow_migrate</span><span class="p">(</span><span class="n">schema_editor</span><span class="o">.</span><span class="n">connection</span><span class="o">.</span><span class="n">alias</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">hints</span><span class="p">):</span> <span class="c1"># We now execute the Python code in a context that contains a 'models'</span> <span class="c1"># object, representing the versioned models as an app registry.</span> <span class="c1"># We could try to override the global cache, but then people will still</span> <span class="c1"># use direct imports, so we go with a documentation approach instead.</span> <span class="bp">self</span><span class="o">.</span><span class="n">code</span><span class="p">(</span><span class="n">from_state</span><span class="o">.</span><span class="n">apps</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">)</span> <span class="k">def</span> <span class="nf">database_backwards</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">,</span> <span class="n">from_state</span><span class="p">,</span> <span class="n">to_state</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_code</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">NotImplementedError</span><span class="p">(</span><span class="s2">"You cannot reverse this operation"</span><span class="p">)</span> <span class="k">if</span> <span class="n">router</span><span class="o">.</span><span class="n">allow_migrate</span><span class="p">(</span><span class="n">schema_editor</span><span class="o">.</span><span class="n">connection</span><span class="o">.</span><span class="n">alias</span><span class="p">,</span> <span class="n">app_label</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">hints</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_code</span><span class="p">(</span><span class="n">from_state</span><span class="o">.</span><span class="n">apps</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">)</span> <span class="k">def</span> <span class="nf">describe</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="s2">"Raw Python operation"</span> <span class="nd">@staticmethod</span> <div class="viewcode-block" id="RunPython.noop"><a class="viewcode-back" href="../../../../../ref/migration-operations.html#django.db.migrations.operations.RunPython.noop">[docs]</a> <span class="k">def</span> <span class="nf">noop</span><span class="p">(</span><span class="n">apps</span><span class="p">,</span> <span class="n">schema_editor</span><span class="p">):</span> <span class="k">return</span> <span class="kc">None</span></div></div> </pre></div> </div> </div> </div> <div class="yui-b" id="sidebar"> <div class="sphinxsidebar" role="navigation" 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