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The view will manage content negotiation and setting the correct renderer on the response.</li> <li>Any <code>APIException</code> exceptions will be caught and mediated into appropriate responses.</li> <li>Incoming requests will be authenticated and appropriate permission and/or throttle checks will be run before dispatching the request to the handler method.</li> </ul> <p>Using the <code>APIView</code> class is pretty much the same as using a regular <code>View</code> class, as usual, the incoming request is dispatched to an appropriate handler method such as <code>.get()</code> or <code>.post()</code>. Additionally, a number of attributes may be set on the class that control various aspects of the API policy.</p> <p>For example:</p> <pre class="prettyprint lang-py"><code>from rest_framework.views import APIView from rest_framework.response import Response from rest_framework import authentication, permissions class ListUsers(APIView): """ View to list all users in the system. * Requires token authentication. * Only admin users are able to access this view. """ authentication_classes = (authentication.TokenAuthentication,) permission_classes = (permissions.IsAdminUser,) def get(self, request, format=None): """ Return a list of all users. """ usernames = [user.username for user in User.objects.all()] return Response(usernames) </code></pre> <h2 id="api-policy-attributes">API policy attributes</h2> <p>The following attributes control the pluggable aspects of API views.</p> <h3 id="renderer_classes">.renderer_classes</h3> <h3 id="parser_classes">.parser_classes</h3> <h3 id="authentication_classes">.authentication_classes</h3> <h3 id="throttle_classes">.throttle_classes</h3> <h3 id="permission_classes">.permission_classes</h3> <h3 id="content_negotiation_class">.content_negotiation_class</h3> <h2 id="api-policy-instantiation-methods">API policy instantiation methods</h2> <p>The following methods are used by REST framework to instantiate the various pluggable API policies. You won't typically need to override these methods.</p> <h3 id="get_renderersself">.get_renderers(self)</h3> <h3 id="get_parsersself">.get_parsers(self)</h3> <h3 id="get_authenticatorsself">.get_authenticators(self)</h3> <h3 id="get_throttlesself">.get_throttles(self)</h3> <h3 id="get_permissionsself">.get_permissions(self)</h3> <h3 id="get_content_negotiatorself">.get_content_negotiator(self)</h3> <h2 id="api-policy-implementation-methods">API policy implementation methods</h2> <p>The following methods are called before dispatching to the handler method.</p> <h3 id="check_permissionsself-request">.check_permissions(self, request)</h3> <h3 id="check_throttlesself-request">.check_throttles(self, request)</h3> <h3 id="perform_content_negotiationself-request-forcefalse">.perform_content_negotiation(self, request, force=False)</h3> <h2 id="dispatch-methods">Dispatch methods</h2> <p>The following methods are called directly by the view's <code>.dispatch()</code> method. These perform any actions that need to occur before or after calling the handler methods such as <code>.get()</code>, <code>.post()</code>, <code>put()</code>, <code>patch()</code> and <code>.delete()</code>.</p> <h3 id="initialself-request-42args-kwargs">.initial(self, request, *args, **kwargs)</h3> <p>Performs any actions that need to occur before the handler method gets called. This method is used to enforce permissions and throttling, and perform content negotiation.</p> <p>You won't typically need to override this method.</p> <h3 id="handle_exceptionself-exc">.handle_exception(self, exc)</h3> <p>Any exception thrown by the handler method will be passed to this method, which either returns a <code>Response</code> instance, or re-raises the exception.</p> <p>The default implementation handles any subclass of <code>rest_framework.exceptions.APIException</code>, as well as Django's <code>Http404</code> and <code>PermissionDenied</code> exceptions, and returns an appropriate error response.</p> <p>If you need to customize the error responses your API returns you should subclass this method.</p> <h3 id="initialize_requestself-request-42args-kwargs">.initialize_request(self, request, *args, **kwargs)</h3> <p>Ensures that the request object that is passed to the handler method is an instance of <code>Request</code>, rather than the usual Django <code>HttpRequest</code>.</p> <p>You won't typically need to override this method.</p> <h3 id="finalize_responseself-request-response-42args-kwargs">.finalize_response(self, request, response, *args, **kwargs)</h3> <p>Ensures that any <code>Response</code> object returned from the handler method will be rendered into the correct content type, as determined by the content negotiation.</p> <p>You won't typically need to override this method.</p> <hr /> <h1 id="function-based-views">Function Based Views</h1> <blockquote> <p>Saying [that Class based views] is always the superior solution is a mistake.</p> <p>— <a href="http://www.boredomandlaziness.org/2012/05/djangos-cbvs-are-not-mistake-but.html">Nick Coghlan</a></p> </blockquote> <p>REST framework also allows you to work with regular function based views. It provides a set of simple decorators that wrap your function based views to ensure they receive an instance of <code>Request</code> (rather than the usual Django <code>HttpRequest</code>) and allows them to return a <code>Response</code> (instead of a Django <code>HttpResponse</code>), and allow you to configure how the request is processed.</p> <h2 id="api_view">@api_view()</h2> <p><strong>Signature:</strong> <code>@api_view(http_method_names)</code></p> <p>The core of this functionality is the <code>api_view</code> decorator, which takes a list of HTTP methods that your view should respond to. For example, this is how you would write a very simple view that just manually returns some data:</p> <pre class="prettyprint lang-py"><code>from rest_framework.decorators import api_view @api_view(['GET']) def hello_world(request): return Response({"message": "Hello, world!"}) </code></pre> <p>This view will use the default renderers, parsers, authentication classes etc specified in the <a href="settings">settings</a>.</p> <h2 id="api-policy-decorators">API policy decorators</h2> <p>To override the default settings, REST framework provides a set of additional decorators which can be added to your views. These must come <em>after</em> (below) the <code>@api_view</code> decorator. For example, to create a view that uses a <a href="throttling">throttle</a> to ensure it can only be called once per day by a particular user, use the <code>@throttle_classes</code> decorator, passing a list of throttle classes:</p> <pre class="prettyprint lang-py"><code>from rest_framework.decorators import api_view, throttle_classes from rest_framework.throttling import UserRateThrottle class OncePerDayUserThrottle(UserRateThrottle): rate = '1/day' @api_view(['GET']) @throttle_classes([OncePerDayUserThrottle]) def view(request): return Response({"message": "Hello for today! See you tomorrow!"}) </code></pre> <p>These decorators correspond to the attributes set on <code>APIView</code> subclasses, described above.</p> <p>The available decorators are:</p> <ul> <li><code>@renderer_classes(...)</code></li> <li><code>@parser_classes(...)</code></li> <li><code>@authentication_classes(...)</code></li> <li><code>@throttle_classes(...)</code></li> <li><code>@permission_classes(...)</code></li> </ul> <p>Each of these decorators takes a single argument which must be a list or tuple of classes.</p> </div><!--/span--> </div><!--/row--> </div><!--/.fluid-container--> </div><!--/.body content--> <div id="push"></div> </div><!--/.wrapper --> <footer class="span12"> <p>Sponsored by <a href="http://dabapps.com/">DabApps</a>.</a></p> </footer> <!-- Le javascript ================================================== --> <!-- Placed at the end of the document so the pages load faster --> <script src="http://www.django-rest-framework.org/js/jquery-1.8.1-min.js"></script> <script src="http://www.django-rest-framework.org/js/prettify-1.0.js"></script> <script src="http://www.django-rest-framework.org/js/bootstrap-2.1.1-min.js"></script> <script> //$('.side-nav').scrollspy() var shiftWindow = function() { scrollBy(0, -50) }; if (location.hash) shiftWindow(); window.addEventListener("hashchange", shiftWindow); $('.dropdown-menu').on('click touchstart', function(event) { event.stopPropagation(); }); // Dynamically force sidenav to no higher than browser window $('.side-nav').css('max-height', window.innerHeight - 130); $(function(){ $(window).resize(function(){ $('.side-nav').css('max-height', window.innerHeight - 130); }); }); </script> </body></html>