<!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.views.decorators.http — 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-views-decorators-http"> <h1>Source code for django.views.decorators.http</h1><div class="highlight"><pre> <span></span><span class="sd">"""</span> <span class="sd">Decorators for views based on HTTP headers.</span> <span class="sd">"""</span> <span class="kn">import</span> <span class="nn">logging</span> <span class="kn">from</span> <span class="nn">calendar</span> <span class="k">import</span> <span class="n">timegm</span> <span class="kn">from</span> <span class="nn">functools</span> <span class="k">import</span> <span class="n">wraps</span> <span class="kn">from</span> <span class="nn">django.http</span> <span class="k">import</span> <span class="p">(</span> <span class="n">HttpResponse</span><span class="p">,</span> <span class="n">HttpResponseNotAllowed</span><span class="p">,</span> <span class="n">HttpResponseNotModified</span><span class="p">,</span> <span class="p">)</span> <span class="kn">from</span> <span class="nn">django.middleware.http</span> <span class="k">import</span> <span class="n">ConditionalGetMiddleware</span> <span class="kn">from</span> <span class="nn">django.utils.decorators</span> <span class="k">import</span> <span class="n">available_attrs</span><span class="p">,</span> <span class="n">decorator_from_middleware</span> <span class="kn">from</span> <span class="nn">django.utils.http</span> <span class="k">import</span> <span class="p">(</span> <span class="n">http_date</span><span class="p">,</span> <span class="n">parse_etags</span><span class="p">,</span> <span class="n">parse_http_date_safe</span><span class="p">,</span> <span class="n">quote_etag</span><span class="p">,</span> <span class="p">)</span> <span class="n">conditional_page</span> <span class="o">=</span> <span class="n">decorator_from_middleware</span><span class="p">(</span><span class="n">ConditionalGetMiddleware</span><span class="p">)</span> <span class="n">logger</span> <span class="o">=</span> <span class="n">logging</span><span class="o">.</span><span class="n">getLogger</span><span class="p">(</span><span class="s1">'django.request'</span><span class="p">)</span> <div class="viewcode-block" id="require_http_methods"><a class="viewcode-back" href="../../../../topics/http/decorators.html#django.views.decorators.http.require_http_methods">[docs]</a><span class="k">def</span> <span class="nf">require_http_methods</span><span class="p">(</span><span class="n">request_method_list</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Decorator to make a view only accept particular request methods. Usage::</span> <span class="sd"> @require_http_methods(["GET", "POST"])</span> <span class="sd"> def my_view(request):</span> <span class="sd"> # I can assume now that only GET or POST requests make it this far</span> <span class="sd"> # ...</span> <span class="sd"> Note that request methods should be in uppercase.</span> <span class="sd"> """</span> <span class="k">def</span> <span class="nf">decorator</span><span class="p">(</span><span class="n">func</span><span class="p">):</span> <span class="nd">@wraps</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="n">assigned</span><span class="o">=</span><span class="n">available_attrs</span><span class="p">(</span><span class="n">func</span><span class="p">))</span> <span class="k">def</span> <span class="nf">inner</span><span class="p">(</span><span class="n">request</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="k">if</span> <span class="n">request</span><span class="o">.</span><span class="n">method</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">request_method_list</span><span class="p">:</span> <span class="n">logger</span><span class="o">.</span><span class="n">warning</span><span class="p">(</span><span class="s1">'Method Not Allowed (</span><span class="si">%s</span><span class="s1">): </span><span class="si">%s</span><span class="s1">'</span><span class="p">,</span> <span class="n">request</span><span class="o">.</span><span class="n">method</span><span class="p">,</span> <span class="n">request</span><span class="o">.</span><span class="n">path</span><span class="p">,</span> <span class="n">extra</span><span class="o">=</span><span class="p">{</span> <span class="s1">'status_code'</span><span class="p">:</span> <span class="mi">405</span><span class="p">,</span> <span class="s1">'request'</span><span class="p">:</span> <span class="n">request</span> <span class="p">}</span> <span class="p">)</span> <span class="k">return</span> <span class="n">HttpResponseNotAllowed</span><span class="p">(</span><span class="n">request_method_list</span><span class="p">)</span> <span class="k">return</span> <span class="n">func</span><span class="p">(</span><span class="n">request</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="k">return</span> <span class="n">inner</span> <span class="k">return</span> <span class="n">decorator</span></div> <span class="n">require_GET</span> <span class="o">=</span> <span class="n">require_http_methods</span><span class="p">([</span><span class="s2">"GET"</span><span class="p">])</span> <span class="n">require_GET</span><span class="o">.</span><span class="n">__doc__</span> <span class="o">=</span> <span class="s2">"Decorator to require that a view only accepts the GET method."</span> <span class="n">require_POST</span> <span class="o">=</span> <span class="n">require_http_methods</span><span class="p">([</span><span class="s2">"POST"</span><span class="p">])</span> <span class="n">require_POST</span><span class="o">.</span><span class="n">__doc__</span> <span class="o">=</span> <span class="s2">"Decorator to require that a view only accepts the POST method."</span> <span class="n">require_safe</span> <span class="o">=</span> <span class="n">require_http_methods</span><span class="p">([</span><span class="s2">"GET"</span><span class="p">,</span> <span class="s2">"HEAD"</span><span class="p">])</span> <span class="n">require_safe</span><span class="o">.</span><span class="n">__doc__</span> <span class="o">=</span> <span class="s2">"Decorator to require that a view only accepts safe methods: GET and HEAD."</span> <span class="k">def</span> <span class="nf">_precondition_failed</span><span class="p">(</span><span class="n">request</span><span class="p">):</span> <span class="n">logger</span><span class="o">.</span><span class="n">warning</span><span class="p">(</span><span class="s1">'Precondition Failed: </span><span class="si">%s</span><span class="s1">'</span><span class="p">,</span> <span class="n">request</span><span class="o">.</span><span class="n">path</span><span class="p">,</span> <span class="n">extra</span><span class="o">=</span><span class="p">{</span> <span class="s1">'status_code'</span><span class="p">:</span> <span class="mi">412</span><span class="p">,</span> <span class="s1">'request'</span><span class="p">:</span> <span class="n">request</span> <span class="p">},</span> <span class="p">)</span> <span class="k">return</span> <span class="n">HttpResponse</span><span class="p">(</span><span class="n">status</span><span class="o">=</span><span class="mi">412</span><span class="p">)</span> <div class="viewcode-block" id="condition"><a class="viewcode-back" href="../../../../topics/http/decorators.html#django.views.decorators.http.condition">[docs]</a><span class="k">def</span> <span class="nf">condition</span><span class="p">(</span><span class="n">etag_func</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">last_modified_func</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Decorator to support conditional retrieval (or change) for a view</span> <span class="sd"> function.</span> <span class="sd"> The parameters are callables to compute the ETag and last modified time for</span> <span class="sd"> the requested resource, respectively. The callables are passed the same</span> <span class="sd"> parameters as the view itself. The Etag function should return a string (or</span> <span class="sd"> None if the resource doesn't exist), whilst the last_modified function</span> <span class="sd"> should return a datetime object (or None if the resource doesn't exist).</span> <span class="sd"> If both parameters are provided, all the preconditions must be met before</span> <span class="sd"> the view is processed.</span> <span class="sd"> This decorator will either pass control to the wrapped view function or</span> <span class="sd"> return an HTTP 304 response (unmodified) or 412 response (preconditions</span> <span class="sd"> failed), depending upon the request method.</span> <span class="sd"> Any behavior marked as "undefined" in the HTTP spec (e.g. If-none-match</span> <span class="sd"> plus If-modified-since headers) will result in the view function being</span> <span class="sd"> called.</span> <span class="sd"> """</span> <span class="k">def</span> <span class="nf">decorator</span><span class="p">(</span><span class="n">func</span><span class="p">):</span> <span class="nd">@wraps</span><span class="p">(</span><span class="n">func</span><span class="p">,</span> <span class="n">assigned</span><span class="o">=</span><span class="n">available_attrs</span><span class="p">(</span><span class="n">func</span><span class="p">))</span> <span class="k">def</span> <span class="nf">inner</span><span class="p">(</span><span class="n">request</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="c1"># Get HTTP request headers</span> <span class="n">if_modified_since</span> <span class="o">=</span> <span class="n">request</span><span class="o">.</span><span class="n">META</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"HTTP_IF_MODIFIED_SINCE"</span><span class="p">)</span> <span class="k">if</span> <span class="n">if_modified_since</span><span class="p">:</span> <span class="n">if_modified_since</span> <span class="o">=</span> <span class="n">parse_http_date_safe</span><span class="p">(</span><span class="n">if_modified_since</span><span class="p">)</span> <span class="n">if_unmodified_since</span> <span class="o">=</span> <span class="n">request</span><span class="o">.</span><span class="n">META</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"HTTP_IF_UNMODIFIED_SINCE"</span><span class="p">)</span> <span class="k">if</span> <span class="n">if_unmodified_since</span><span class="p">:</span> <span class="n">if_unmodified_since</span> <span class="o">=</span> <span class="n">parse_http_date_safe</span><span class="p">(</span><span class="n">if_unmodified_since</span><span class="p">)</span> <span class="n">if_none_match</span> <span class="o">=</span> <span class="n">request</span><span class="o">.</span><span class="n">META</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"HTTP_IF_NONE_MATCH"</span><span class="p">)</span> <span class="n">if_match</span> <span class="o">=</span> <span class="n">request</span><span class="o">.</span><span class="n">META</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s2">"HTTP_IF_MATCH"</span><span class="p">)</span> <span class="n">etags</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">if</span> <span class="n">if_none_match</span> <span class="ow">or</span> <span class="n">if_match</span><span class="p">:</span> <span class="c1"># There can be more than one ETag in the request, so we</span> <span class="c1"># consider the list of values.</span> <span class="k">try</span><span class="p">:</span> <span class="n">etags</span> <span class="o">=</span> <span class="n">parse_etags</span><span class="p">(</span><span class="n">if_none_match</span> <span class="ow">or</span> <span class="n">if_match</span><span class="p">)</span> <span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span> <span class="c1"># In case of invalid etag ignore all ETag headers.</span> <span class="c1"># Apparently Opera sends invalidly quoted headers at times</span> <span class="c1"># (we should be returning a 400 response, but that's a</span> <span class="c1"># little extreme) -- this is Django bug #10681.</span> <span class="n">if_none_match</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">if_match</span> <span class="o">=</span> <span class="kc">None</span> <span class="c1"># Compute values (if any) for the requested resource.</span> <span class="k">def</span> <span class="nf">get_last_modified</span><span class="p">():</span> <span class="k">if</span> <span class="n">last_modified_func</span><span class="p">:</span> <span class="n">dt</span> <span class="o">=</span> <span class="n">last_modified_func</span><span class="p">(</span><span class="n">request</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="k">if</span> <span class="n">dt</span><span class="p">:</span> <span class="k">return</span> <span class="n">timegm</span><span class="p">(</span><span class="n">dt</span><span class="o">.</span><span class="n">utctimetuple</span><span class="p">())</span> <span class="n">res_etag</span> <span class="o">=</span> <span class="n">etag_func</span><span class="p">(</span><span class="n">request</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="k">if</span> <span class="n">etag_func</span> <span class="k">else</span> <span class="kc">None</span> <span class="n">res_last_modified</span> <span class="o">=</span> <span class="n">get_last_modified</span><span class="p">()</span> <span class="n">response</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">if</span> <span class="ow">not</span> <span class="p">((</span><span class="n">if_match</span> <span class="ow">and</span> <span class="n">if_modified_since</span><span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="n">if_none_match</span> <span class="ow">and</span> <span class="n">if_unmodified_since</span><span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="n">if_modified_since</span> <span class="ow">and</span> <span class="n">if_unmodified_since</span><span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="n">if_match</span> <span class="ow">and</span> <span class="n">if_none_match</span><span class="p">)):</span> <span class="c1"># We only get here if no undefined combinations of headers are</span> <span class="c1"># specified.</span> <span class="k">if</span> <span class="p">((</span><span class="n">if_none_match</span> <span class="ow">and</span> <span class="p">(</span><span class="n">res_etag</span> <span class="ow">in</span> <span class="n">etags</span> <span class="ow">or</span> <span class="s2">"*"</span> <span class="ow">in</span> <span class="n">etags</span> <span class="ow">and</span> <span class="n">res_etag</span><span class="p">))</span> <span class="ow">and</span> <span class="p">(</span><span class="ow">not</span> <span class="n">if_modified_since</span> <span class="ow">or</span> <span class="p">(</span><span class="n">res_last_modified</span> <span class="ow">and</span> <span class="n">if_modified_since</span> <span class="ow">and</span> <span class="n">res_last_modified</span> <span class="o"><=</span> <span class="n">if_modified_since</span><span class="p">))):</span> <span class="k">if</span> <span class="n">request</span><span class="o">.</span><span class="n">method</span> <span class="ow">in</span> <span class="p">(</span><span class="s2">"GET"</span><span class="p">,</span> <span class="s2">"HEAD"</span><span class="p">):</span> <span class="n">response</span> <span class="o">=</span> <span class="n">HttpResponseNotModified</span><span class="p">()</span> <span class="k">else</span><span class="p">:</span> <span class="n">response</span> <span class="o">=</span> <span class="n">_precondition_failed</span><span class="p">(</span><span class="n">request</span><span class="p">)</span> <span class="k">elif</span> <span class="p">(</span><span class="n">if_match</span> <span class="ow">and</span> <span class="p">((</span><span class="ow">not</span> <span class="n">res_etag</span> <span class="ow">and</span> <span class="s2">"*"</span> <span class="ow">in</span> <span class="n">etags</span><span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="n">res_etag</span> <span class="ow">and</span> <span class="n">res_etag</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">etags</span><span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="n">res_last_modified</span> <span class="ow">and</span> <span class="n">if_unmodified_since</span> <span class="ow">and</span> <span class="n">res_last_modified</span> <span class="o">></span> <span class="n">if_unmodified_since</span><span class="p">))):</span> <span class="n">response</span> <span class="o">=</span> <span class="n">_precondition_failed</span><span class="p">(</span><span class="n">request</span><span class="p">)</span> <span class="k">elif</span> <span class="p">(</span><span class="ow">not</span> <span class="n">if_none_match</span> <span class="ow">and</span> <span class="n">request</span><span class="o">.</span><span class="n">method</span> <span class="ow">in</span> <span class="p">(</span><span class="s2">"GET"</span><span class="p">,</span> <span class="s2">"HEAD"</span><span class="p">)</span> <span class="ow">and</span> <span class="n">res_last_modified</span> <span class="ow">and</span> <span class="n">if_modified_since</span> <span class="ow">and</span> <span class="n">res_last_modified</span> <span class="o"><=</span> <span class="n">if_modified_since</span><span class="p">):</span> <span class="n">response</span> <span class="o">=</span> <span class="n">HttpResponseNotModified</span><span class="p">()</span> <span class="k">elif</span> <span class="p">(</span><span class="ow">not</span> <span class="n">if_match</span> <span class="ow">and</span> <span class="n">res_last_modified</span> <span class="ow">and</span> <span class="n">if_unmodified_since</span> <span class="ow">and</span> <span class="n">res_last_modified</span> <span class="o">></span> <span class="n">if_unmodified_since</span><span class="p">):</span> <span class="n">response</span> <span class="o">=</span> <span class="n">_precondition_failed</span><span class="p">(</span><span class="n">request</span><span class="p">)</span> <span class="k">if</span> <span class="n">response</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">response</span> <span class="o">=</span> <span class="n">func</span><span class="p">(</span><span class="n">request</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="c1"># Set relevant headers on the response if they don't already exist.</span> <span class="k">if</span> <span class="n">res_last_modified</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">response</span><span class="o">.</span><span class="n">has_header</span><span class="p">(</span><span class="s1">'Last-Modified'</span><span class="p">):</span> <span class="n">response</span><span class="p">[</span><span class="s1">'Last-Modified'</span><span class="p">]</span> <span class="o">=</span> <span class="n">http_date</span><span class="p">(</span><span class="n">res_last_modified</span><span class="p">)</span> <span class="k">if</span> <span class="n">res_etag</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">response</span><span class="o">.</span><span class="n">has_header</span><span class="p">(</span><span class="s1">'ETag'</span><span class="p">):</span> <span class="n">response</span><span class="p">[</span><span class="s1">'ETag'</span><span class="p">]</span> <span class="o">=</span> <span class="n">quote_etag</span><span class="p">(</span><span class="n">res_etag</span><span class="p">)</span> <span class="k">return</span> <span class="n">response</span> <span class="k">return</span> <span class="n">inner</span> <span class="k">return</span> <span class="n">decorator</span></div> <span class="c1"># Shortcut decorators for common cases based on ETag or Last-Modified only</span> <div class="viewcode-block" id="etag"><a class="viewcode-back" href="../../../../topics/http/decorators.html#django.views.decorators.http.etag">[docs]</a><span class="k">def</span> <span class="nf">etag</span><span class="p">(</span><span class="n">etag_func</span><span class="p">):</span> <span class="k">return</span> <span class="n">condition</span><span class="p">(</span><span class="n">etag_func</span><span class="o">=</span><span class="n">etag_func</span><span class="p">)</span></div> <div class="viewcode-block" id="last_modified"><a class="viewcode-back" href="../../../../topics/http/decorators.html#django.views.decorators.http.last_modified">[docs]</a><span class="k">def</span> <span class="nf">last_modified</span><span class="p">(</span><span class="n">last_modified_func</span><span class="p">):</span> <span class="k">return</span> <span class="n">condition</span><span class="p">(</span><span class="n">last_modified_func</span><span class="o">=</span><span class="n">last_modified_func</span><span class="p">)</span></div> </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 1.8.19 documentation</a> <ul><li><a href="../../../index.html">Module code</a> <ul><li><a href="../../../django.html">django</a> <ul><li>django.views.decorators.http</li></ul> </li></ul></li></ul> </li> </ul> <div id="searchbox" style="display: none" role="search"> <h3>Quick search</h3> <form class="search" action="../../../../search.html" method="get"> <div><input type="text" name="q" /></div> <div><input type="submit" value="Go" /></div> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> </div> <script 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