<!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="X-UA-Compatible" content="IE=Edge" />
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>django.utils.module_loading — Django 1.11.20 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" id="documentation_options" data-url_root="../../../" src="../../../_static/documentation_options.js"></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>
<script type="text/javascript" src="../../../_static/language_data.js"></script>
<link rel="index" title="Index" href="../../../genindex.html" />
<link rel="search" title="Search" href="../../../search.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>
<div class="document">
<div id="custom-doc" class="yui-t6">
<div id="hd">
<h1><a href="../../../index.html">Django 1.11.20 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-utils-module_loading">
<h1>Source code for django.utils.module_loading</h1><div class="highlight"><pre>
<span></span><span class="kn">import</span> <span class="nn">copy</span>
<span class="kn">import</span> <span class="nn">os</span>
<span class="kn">import</span> <span class="nn">sys</span>
<span class="kn">from</span> <span class="nn">importlib</span> <span class="k">import</span> <span class="n">import_module</span>
<span class="kn">from</span> <span class="nn">django.utils</span> <span class="k">import</span> <span class="n">six</span>
<div class="viewcode-block" id="import_string"><a class="viewcode-back" href="../../../ref/utils.html#django.utils.module_loading.import_string">[docs]</a><span class="k">def</span> <span class="nf">import_string</span><span class="p">(</span><span class="n">dotted_path</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Import a dotted module path and return the attribute/class designated by the</span>
<span class="sd"> last name in the path. Raise ImportError if the import failed.</span>
<span class="sd"> """</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">module_path</span><span class="p">,</span> <span class="n">class_name</span> <span class="o">=</span> <span class="n">dotted_path</span><span class="o">.</span><span class="n">rsplit</span><span class="p">(</span><span class="s1">'.'</span><span class="p">,</span> <span class="mi">1</span><span class="p">)</span>
<span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span>
<span class="n">msg</span> <span class="o">=</span> <span class="s2">"</span><span class="si">%s</span><span class="s2"> doesn't look like a module path"</span> <span class="o">%</span> <span class="n">dotted_path</span>
<span class="n">six</span><span class="o">.</span><span class="n">reraise</span><span class="p">(</span><span class="ne">ImportError</span><span class="p">,</span> <span class="ne">ImportError</span><span class="p">(</span><span class="n">msg</span><span class="p">),</span> <span class="n">sys</span><span class="o">.</span><span class="n">exc_info</span><span class="p">()[</span><span class="mi">2</span><span class="p">])</span>
<span class="n">module</span> <span class="o">=</span> <span class="n">import_module</span><span class="p">(</span><span class="n">module_path</span><span class="p">)</span>
<span class="k">try</span><span class="p">:</span>
<span class="k">return</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">module</span><span class="p">,</span> <span class="n">class_name</span><span class="p">)</span>
<span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span>
<span class="n">msg</span> <span class="o">=</span> <span class="s1">'Module "</span><span class="si">%s</span><span class="s1">" does not define a "</span><span class="si">%s</span><span class="s1">" attribute/class'</span> <span class="o">%</span> <span class="p">(</span>
<span class="n">module_path</span><span class="p">,</span> <span class="n">class_name</span><span class="p">)</span>
<span class="n">six</span><span class="o">.</span><span class="n">reraise</span><span class="p">(</span><span class="ne">ImportError</span><span class="p">,</span> <span class="ne">ImportError</span><span class="p">(</span><span class="n">msg</span><span class="p">),</span> <span class="n">sys</span><span class="o">.</span><span class="n">exc_info</span><span class="p">()[</span><span class="mi">2</span><span class="p">])</span></div>
<span class="k">def</span> <span class="nf">autodiscover_modules</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="sd">"""</span>
<span class="sd"> Auto-discover INSTALLED_APPS modules and fail silently when</span>
<span class="sd"> not present. This forces an import on them to register any admin bits they</span>
<span class="sd"> may want.</span>
<span class="sd"> You may provide a register_to keyword parameter as a way to access a</span>
<span class="sd"> registry. This register_to object must have a _registry instance variable</span>
<span class="sd"> to access it.</span>
<span class="sd"> """</span>
<span class="kn">from</span> <span class="nn">django.apps</span> <span class="k">import</span> <span class="n">apps</span>
<span class="n">register_to</span> <span class="o">=</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s1">'register_to'</span><span class="p">)</span>
<span class="k">for</span> <span class="n">app_config</span> <span class="ow">in</span> <span class="n">apps</span><span class="o">.</span><span class="n">get_app_configs</span><span class="p">():</span>
<span class="k">for</span> <span class="n">module_to_search</span> <span class="ow">in</span> <span class="n">args</span><span class="p">:</span>
<span class="c1"># Attempt to import the app's module.</span>
<span class="k">try</span><span class="p">:</span>
<span class="k">if</span> <span class="n">register_to</span><span class="p">:</span>
<span class="n">before_import_registry</span> <span class="o">=</span> <span class="n">copy</span><span class="o">.</span><span class="n">copy</span><span class="p">(</span><span class="n">register_to</span><span class="o">.</span><span class="n">_registry</span><span class="p">)</span>
<span class="n">import_module</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">app_config</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">module_to_search</span><span class="p">))</span>
<span class="k">except</span> <span class="ne">Exception</span><span class="p">:</span>
<span class="c1"># Reset the registry to the state before the last import</span>
<span class="c1"># as this import will have to reoccur on the next request and</span>
<span class="c1"># this could raise NotRegistered and AlreadyRegistered</span>
<span class="c1"># exceptions (see #8245).</span>
<span class="k">if</span> <span class="n">register_to</span><span class="p">:</span>
<span class="n">register_to</span><span class="o">.</span><span class="n">_registry</span> <span class="o">=</span> <span class="n">before_import_registry</span>
<span class="c1"># Decide whether to bubble up this error. If the app just</span>
<span class="c1"># doesn't have the module in question, we can ignore the error</span>
<span class="c1"># attempting to import it, otherwise we want it to bubble up.</span>
<span class="k">if</span> <span class="n">module_has_submodule</span><span class="p">(</span><span class="n">app_config</span><span class="o">.</span><span class="n">module</span><span class="p">,</span> <span class="n">module_to_search</span><span class="p">):</span>
<span class="k">raise</span>
<span class="k">if</span> <span class="n">six</span><span class="o">.</span><span class="n">PY3</span><span class="p">:</span>
<span class="kn">from</span> <span class="nn">importlib.util</span> <span class="k">import</span> <span class="n">find_spec</span> <span class="k">as</span> <span class="n">importlib_find</span>
<span class="k">def</span> <span class="nf">module_has_submodule</span><span class="p">(</span><span class="n">package</span><span class="p">,</span> <span class="n">module_name</span><span class="p">):</span>
<span class="sd">"""See if 'module' is in 'package'."""</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">package_name</span> <span class="o">=</span> <span class="n">package</span><span class="o">.</span><span class="vm">__name__</span>
<span class="n">package_path</span> <span class="o">=</span> <span class="n">package</span><span class="o">.</span><span class="n">__path__</span>
<span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span>
<span class="c1"># package isn't a package.</span>
<span class="k">return</span> <span class="kc">False</span>
<span class="n">full_module_name</span> <span class="o">=</span> <span class="n">package_name</span> <span class="o">+</span> <span class="s1">'.'</span> <span class="o">+</span> <span class="n">module_name</span>
<span class="k">return</span> <span class="n">importlib_find</span><span class="p">(</span><span class="n">full_module_name</span><span class="p">,</span> <span class="n">package_path</span><span class="p">)</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span>
<span class="k">else</span><span class="p">:</span>
<span class="kn">import</span> <span class="nn">imp</span>
<span class="k">def</span> <span class="nf">module_has_submodule</span><span class="p">(</span><span class="n">package</span><span class="p">,</span> <span class="n">module_name</span><span class="p">):</span>
<span class="sd">"""See if 'module' is in 'package'."""</span>
<span class="n">name</span> <span class="o">=</span> <span class="s2">"."</span><span class="o">.</span><span class="n">join</span><span class="p">([</span><span class="n">package</span><span class="o">.</span><span class="vm">__name__</span><span class="p">,</span> <span class="n">module_name</span><span class="p">])</span>
<span class="k">try</span><span class="p">:</span>
<span class="c1"># None indicates a cached miss; see mark_miss() in Python/import.c.</span>
<span class="k">return</span> <span class="n">sys</span><span class="o">.</span><span class="n">modules</span><span class="p">[</span><span class="n">name</span><span class="p">]</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span>
<span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span>
<span class="k">pass</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">package_path</span> <span class="o">=</span> <span class="n">package</span><span class="o">.</span><span class="n">__path__</span> <span class="c1"># No __path__, then not a package.</span>
<span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span>
<span class="c1"># Since the remainder of this function assumes that we're dealing with</span>
<span class="c1"># a package (module with a __path__), so if it's not, then bail here.</span>
<span class="k">return</span> <span class="kc">False</span>
<span class="k">for</span> <span class="n">finder</span> <span class="ow">in</span> <span class="n">sys</span><span class="o">.</span><span class="n">meta_path</span><span class="p">:</span>
<span class="k">if</span> <span class="n">finder</span><span class="o">.</span><span class="n">find_module</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">package_path</span><span class="p">):</span>
<span class="k">return</span> <span class="kc">True</span>
<span class="k">for</span> <span class="n">entry</span> <span class="ow">in</span> <span class="n">package_path</span><span class="p">:</span>
<span class="k">try</span><span class="p">:</span>
<span class="c1"># Try the cached finder.</span>
<span class="n">finder</span> <span class="o">=</span> <span class="n">sys</span><span class="o">.</span><span class="n">path_importer_cache</span><span class="p">[</span><span class="n">entry</span><span class="p">]</span>
<span class="k">if</span> <span class="n">finder</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
<span class="c1"># Implicit import machinery should be used.</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">file_</span><span class="p">,</span> <span class="n">_</span><span class="p">,</span> <span class="n">_</span> <span class="o">=</span> <span class="n">imp</span><span class="o">.</span><span class="n">find_module</span><span class="p">(</span><span class="n">module_name</span><span class="p">,</span> <span class="p">[</span><span class="n">entry</span><span class="p">])</span>
<span class="k">if</span> <span class="n">file_</span><span class="p">:</span>
<span class="n">file_</span><span class="o">.</span><span class="n">close</span><span class="p">()</span>
<span class="k">return</span> <span class="kc">True</span>
<span class="k">except</span> <span class="ne">ImportError</span><span class="p">:</span>
<span class="k">continue</span>
<span class="c1"># Else see if the finder knows of a loader.</span>
<span class="k">elif</span> <span class="n">finder</span><span class="o">.</span><span class="n">find_module</span><span class="p">(</span><span class="n">name</span><span class="p">):</span>
<span class="k">return</span> <span class="kc">True</span>
<span class="k">else</span><span class="p">:</span>
<span class="k">continue</span>
<span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span>
<span class="c1"># No cached finder, so try and make one.</span>
<span class="k">for</span> <span class="n">hook</span> <span class="ow">in</span> <span class="n">sys</span><span class="o">.</span><span class="n">path_hooks</span><span class="p">:</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">finder</span> <span class="o">=</span> <span class="n">hook</span><span class="p">(</span><span class="n">entry</span><span class="p">)</span>
<span class="c1"># XXX Could cache in sys.path_importer_cache</span>
<span class="k">if</span> <span class="n">finder</span><span class="o">.</span><span class="n">find_module</span><span class="p">(</span><span class="n">name</span><span class="p">):</span>
<span class="k">return</span> <span class="kc">True</span>
<span class="k">else</span><span class="p">:</span>
<span class="c1"># Once a finder is found, stop the search.</span>
<span class="k">break</span>
<span class="k">except</span> <span class="ne">ImportError</span><span class="p">:</span>
<span class="c1"># Continue the search for a finder.</span>
<span class="k">continue</span>
<span class="k">else</span><span class="p">:</span>
<span class="c1"># No finder found.</span>
<span class="c1"># Try the implicit import machinery if searching a directory.</span>
<span class="k">if</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">isdir</span><span class="p">(</span><span class="n">entry</span><span class="p">):</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">file_</span><span class="p">,</span> <span class="n">_</span><span class="p">,</span> <span class="n">_</span> <span class="o">=</span> <span class="n">imp</span><span class="o">.</span><span class="n">find_module</span><span class="p">(</span><span class="n">module_name</span><span class="p">,</span> <span class="p">[</span><span class="n">entry</span><span class="p">])</span>
<span class="k">if</span> <span class="n">file_</span><span class="p">:</span>
<span class="n">file_</span><span class="o">.</span><span class="n">close</span><span class="p">()</span>
<span class="k">return</span> <span class="kc">True</span>
<span class="k">except</span> <span class="ne">ImportError</span><span class="p">:</span>
<span class="k">pass</span>
<span class="c1"># XXX Could insert None or NullImporter</span>
<span class="k">else</span><span class="p">:</span>
<span class="c1"># Exhausted the search, so the module cannot be found.</span>
<span class="k">return</span> <span class="kc">False</span>
<span class="k">def</span> <span class="nf">module_dir</span><span class="p">(</span><span class="n">module</span><span class="p">):</span>
<span class="sd">"""</span>
<span class="sd"> Find the name of the directory that contains a module, if possible.</span>
<span class="sd"> Raise ValueError otherwise, e.g. for namespace packages that are split</span>
<span class="sd"> over several directories.</span>
<span class="sd"> """</span>
<span class="c1"># Convert to list because _NamespacePath does not support indexing on 3.3.</span>
<span class="n">paths</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="nb">getattr</span><span class="p">(</span><span class="n">module</span><span class="p">,</span> <span class="s1">'__path__'</span><span class="p">,</span> <span class="p">[]))</span>
<span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">paths</span><span class="p">)</span> <span class="o">==</span> <span class="mi">1</span><span class="p">:</span>
<span class="k">return</span> <span class="n">paths</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">filename</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">module</span><span class="p">,</span> <span class="s1">'__file__'</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span>
<span class="k">if</span> <span class="n">filename</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span>
<span class="k">return</span> <span class="n">os</span><span class="o">.</span><span class="n">path</span><span class="o">.</span><span class="n">dirname</span><span class="p">(</span><span class="n">filename</span><span class="p">)</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"Cannot determine directory containing </span><span class="si">%s</span><span class="s2">"</span> <span class="o">%</span> <span class="n">module</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">
<div id="searchbox" style="display: none" role="search">
<h3>Quick search</h3>
<div class="searchformwrapper">
<form class="search" action="../../../search.html" method="get">
<input type="text" name="q" />
<input type="submit" value="Go" />
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>
</div>
</div>
<script type="text/javascript">$('#searchbox').show(0);</script>
</div>
</div>
<h3>Last update:</h3>
<p class="topless">Feb 11, 2019</p>
</div>
</div>
<div id="ft">
<div class="nav">
<a href="../../index.html" title="Module code" accesskey="U">up</a></div>
</div>
</div>
<div class="clearer"></div>
</div>
</body>
</html>
