django-rest-framework/api-guide/viewsets/index.html
2015-11-04 14:59:23 +00:00

656 lines
28 KiB
HTML

<!DOCTYPE html>
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta charset="utf-8">
<title>Viewsets - Django REST framework</title>
<link href="../../img/favicon.ico" rel="icon" type="image/x-icon">
<link rel="canonical" href="http://www.django-rest-framework.org/api-guide/viewsets/" />
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="description" content="Django, API, REST, Viewsets">
<meta name="author" content="Tom Christie">
<!-- Le styles -->
<link href="../../css/prettify.css" rel="stylesheet">
<link href="../../css/bootstrap.css" rel="stylesheet">
<link href="../../css/bootstrap-responsive.css" rel="stylesheet">
<link href="../../css/default.css" rel="stylesheet">
<!-- Le HTML5 shim, for IE6-8 support of HTML5 elements -->
<!--[if lt IE 9]>
<script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
<script type="text/javascript">
var _gaq = _gaq || [];
_gaq.push(['_setAccount', 'UA-18852272-2']);
_gaq.push(['_trackPageview']);
(function() {
var ga = document.createElement('script');
ga.type = 'text/javascript';
ga.async = true;
ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
var s = document.getElementsByTagName('script')[0];
s.parentNode.insertBefore(ga, s);
})();
</script>
<style>
span.fusion-wrap a {
display: block;
margin-top: 10px;
color: black;
}
a.fusion-poweredby {
display: block;
margin-top: 10px;
}
@media (max-width: 767px) {
div.promo {
display: none;
}
}
</style>
</head>
<body onload="prettyPrint()" class="-page">
<div class="wrapper">
<div class="navbar navbar-inverse navbar-fixed-top">
<div class="navbar-inner">
<div class="container-fluid">
<a class="repo-link btn btn-primary btn-small" href="https://github.com/tomchristie/django-rest-framework/tree/master">GitHub</a>
<a class="repo-link btn btn-inverse btn-small " rel="prev" href="../routers/">
Next <i class="icon-arrow-right icon-white"></i>
</a>
<a class="repo-link btn btn-inverse btn-small " rel="next" href="../generic-views/">
<i class="icon-arrow-left icon-white"></i> Previous
</a>
<a id="search_modal_show" class="repo-link btn btn-inverse btn-small" href="#mkdocs_search_modal" data-toggle="modal" data-target="#mkdocs_search_modal"><i class="icon-search icon-white"></i> Search</a>
<a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</a>
<a class="brand" href="http://www.django-rest-framework.org">Django REST framework</a>
<div class="nav-collapse collapse">
<!-- Main navigation -->
<ul class="nav navbar-nav">
<li >
<a href="../..">Home</a>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Tutorial <b class="caret"></b></a>
<ul class="dropdown-menu">
<li >
<a href="../../tutorial/quickstart/">Quickstart</a>
</li>
<li >
<a href="../../tutorial/1-serialization/">1 - Serialization</a>
</li>
<li >
<a href="../../tutorial/2-requests-and-responses/">2 - Requests and responses</a>
</li>
<li >
<a href="../../tutorial/3-class-based-views/">3 - Class based views</a>
</li>
<li >
<a href="../../tutorial/4-authentication-and-permissions/">4 - Authentication and permissions</a>
</li>
<li >
<a href="../../tutorial/5-relationships-and-hyperlinked-apis/">5 - Relationships and hyperlinked APIs</a>
</li>
<li >
<a href="../../tutorial/6-viewsets-and-routers/">6 - Viewsets and routers</a>
</li>
</ul>
</li>
<li class="dropdown active">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">API Guide <b class="caret"></b></a>
<ul class="dropdown-menu">
<li >
<a href="../requests/">Requests</a>
</li>
<li >
<a href="../responses/">Responses</a>
</li>
<li >
<a href="../views/">Views</a>
</li>
<li >
<a href="../generic-views/">Generic views</a>
</li>
<li class="active" >
<a href="./">Viewsets</a>
</li>
<li >
<a href="../routers/">Routers</a>
</li>
<li >
<a href="../parsers/">Parsers</a>
</li>
<li >
<a href="../renderers/">Renderers</a>
</li>
<li >
<a href="../serializers/">Serializers</a>
</li>
<li >
<a href="../fields/">Serializer fields</a>
</li>
<li >
<a href="../relations/">Serializer relations</a>
</li>
<li >
<a href="../validators/">Validators</a>
</li>
<li >
<a href="../authentication/">Authentication</a>
</li>
<li >
<a href="../permissions/">Permissions</a>
</li>
<li >
<a href="../throttling/">Throttling</a>
</li>
<li >
<a href="../filtering/">Filtering</a>
</li>
<li >
<a href="../pagination/">Pagination</a>
</li>
<li >
<a href="../versioning/">Versioning</a>
</li>
<li >
<a href="../content-negotiation/">Content negotiation</a>
</li>
<li >
<a href="../metadata/">Metadata</a>
</li>
<li >
<a href="../format-suffixes/">Format suffixes</a>
</li>
<li >
<a href="../reverse/">Returning URLs</a>
</li>
<li >
<a href="../exceptions/">Exceptions</a>
</li>
<li >
<a href="../status-codes/">Status codes</a>
</li>
<li >
<a href="../testing/">Testing</a>
</li>
<li >
<a href="../settings/">Settings</a>
</li>
</ul>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Topics <b class="caret"></b></a>
<ul class="dropdown-menu">
<li >
<a href="../../topics/documenting-your-api/">Documenting your API</a>
</li>
<li >
<a href="../../topics/internationalization/">Internationalization</a>
</li>
<li >
<a href="../../topics/ajax-csrf-cors/">AJAX, CSRF & CORS</a>
</li>
<li >
<a href="../../topics/html-and-forms/">HTML & Forms</a>
</li>
<li >
<a href="../../topics/browser-enhancements/">Browser Enhancements</a>
</li>
<li >
<a href="../../topics/browsable-api/">The Browsable API</a>
</li>
<li >
<a href="../../topics/rest-hypermedia-hateoas/">REST, Hypermedia & HATEOAS</a>
</li>
<li >
<a href="../../topics/third-party-resources/">Third Party Resources</a>
</li>
<li >
<a href="../../topics/contributing/">Contributing to REST framework</a>
</li>
<li >
<a href="../../topics/project-management/">Project management</a>
</li>
<li >
<a href="../../topics/3.0-announcement/">3.0 Announcement</a>
</li>
<li >
<a href="../../topics/3.1-announcement/">3.1 Announcement</a>
</li>
<li >
<a href="../../topics/3.2-announcement/">3.2 Announcement</a>
</li>
<li >
<a href="../../topics/3.3-announcement/">3.3 Announcement</a>
</li>
<li >
<a href="../../topics/kickstarter-announcement/">Kickstarter Announcement</a>
</li>
<li >
<a href="../../topics/release-notes/">Release Notes</a>
</li>
</ul>
</li>
</ul>
</div>
<!--/.nav-collapse -->
</div>
</div>
</div>
<div class="body-content">
<div class="container-fluid">
<!-- Search Modal -->
<div id="mkdocs_search_modal" class="modal hide fade" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">&times;</button>
<h3 id="myModalLabel">Documentation search</h3>
</div>
<div class="modal-body">
<form role="form" autocomplete="off">
<div class="form-group">
<input type="text" name="q" class="form-control" placeholder="Search..." id="mkdocs-search-query">
</div>
</form>
<div id="mkdocs-search-results"></div>
</div>
<div class="modal-footer">
<button class="btn" data-dismiss="modal" aria-hidden="true">Close</button>
</div>
</div>
<div class="row-fluid">
<div class="span3">
<div id="table-of-contents">
<ul class="nav nav-list side-nav well sidebar-nav-fixed">
<li class="main">
<a href="#viewsets">ViewSets</a>
</li>
<li>
<a href="#example">Example</a>
</li>
<li>
<a href="#marking-extra-actions-for-routing">Marking extra actions for routing</a>
</li>
<li class="main">
<a href="#api-reference">API Reference</a>
</li>
<li>
<a href="#viewset">ViewSet</a>
</li>
<li>
<a href="#genericviewset">GenericViewSet</a>
</li>
<li>
<a href="#modelviewset">ModelViewSet</a>
</li>
<li>
<a href="#readonlymodelviewset">ReadOnlyModelViewSet</a>
</li>
<li class="main">
<a href="#custom-viewset-base-classes">Custom ViewSet base classes</a>
</li>
<li>
<a href="#example_3">Example</a>
</li>
</ul>
</div>
</div>
<div id="main-content" class="span9">
<a class="github" href="https://github.com/tomchristie/django-rest-framework/tree/master/rest_framework/viewsets.py">
<span class="label label-info">viewsets.py</span>
</a>
<h1 id="viewsets"><a class="toclink" href="#viewsets">ViewSets</a></h1>
<blockquote>
<p>After routing has determined which controller to use for a request, your controller is responsible for making sense of the request and producing the appropriate output.</p>
<p>&mdash; <a href="http://guides.rubyonrails.org/routing.html">Ruby on Rails Documentation</a></p>
</blockquote>
<p>Django REST framework allows you to combine the logic for a set of related views in a single class, called a <code>ViewSet</code>. In other frameworks you may also find conceptually similar implementations named something like 'Resources' or 'Controllers'.</p>
<p>A <code>ViewSet</code> class is simply <strong>a type of class-based View, that does not provide any method handlers</strong> such as <code>.get()</code> or <code>.post()</code>, and instead provides actions such as <code>.list()</code> and <code>.create()</code>.</p>
<p>The method handlers for a <code>ViewSet</code> are only bound to the corresponding actions at the point of finalizing the view, using the <code>.as_view()</code> method.</p>
<p>Typically, rather than explicitly registering the views in a viewset in the urlconf, you'll register the viewset with a router class, that automatically determines the urlconf for you.</p>
<h2 id="example"><a class="toclink" href="#example">Example</a></h2>
<p>Let's define a simple viewset that can be used to list or retrieve all the users in the system.</p>
<pre><code>from django.contrib.auth.models import User
from django.shortcuts import get_object_or_404
from myapps.serializers import UserSerializer
from rest_framework import viewsets
from rest_framework.response import Response
class UserViewSet(viewsets.ViewSet):
"""
A simple ViewSet for listing or retrieving users.
"""
def list(self, request):
queryset = User.objects.all()
serializer = UserSerializer(queryset, many=True)
return Response(serializer.data)
def retrieve(self, request, pk=None):
queryset = User.objects.all()
user = get_object_or_404(queryset, pk=pk)
serializer = UserSerializer(user)
return Response(serializer.data)
</code></pre>
<p>If we need to, we can bind this viewset into two separate views, like so:</p>
<pre><code>user_list = UserViewSet.as_view({'get': 'list'})
user_detail = UserViewSet.as_view({'get': 'retrieve'})
</code></pre>
<p>Typically we wouldn't do this, but would instead register the viewset with a router, and allow the urlconf to be automatically generated.</p>
<pre><code>from myapp.views import UserViewSet
from rest_framework.routers import DefaultRouter
router = DefaultRouter()
router.register(r'users', UserViewSet)
urlpatterns = router.urls
</code></pre>
<p>Rather than writing your own viewsets, you'll often want to use the existing base classes that provide a default set of behavior. For example:</p>
<pre><code>class UserViewSet(viewsets.ModelViewSet):
"""
A viewset for viewing and editing user instances.
"""
serializer_class = UserSerializer
queryset = User.objects.all()
</code></pre>
<p>There are two main advantages of using a <code>ViewSet</code> class over using a <code>View</code> class.</p>
<ul>
<li>Repeated logic can be combined into a single class. In the above example, we only need to specify the <code>queryset</code> once, and it'll be used across multiple views.</li>
<li>By using routers, we no longer need to deal with wiring up the URL conf ourselves.</li>
</ul>
<p>Both of these come with a trade-off. Using regular views and URL confs is more explicit and gives you more control. ViewSets are helpful if you want to get up and running quickly, or when you have a large API and you want to enforce a consistent URL configuration throughout.</p>
<h2 id="marking-extra-actions-for-routing"><a class="toclink" href="#marking-extra-actions-for-routing">Marking extra actions for routing</a></h2>
<p>The default routers included with REST framework will provide routes for a standard set of create/retrieve/update/destroy style operations, as shown below:</p>
<pre><code>class UserViewSet(viewsets.ViewSet):
"""
Example empty viewset demonstrating the standard
actions that will be handled by a router class.
If you're using format suffixes, make sure to also include
the `format=None` keyword argument for each action.
"""
def list(self, request):
pass
def create(self, request):
pass
def retrieve(self, request, pk=None):
pass
def update(self, request, pk=None):
pass
def partial_update(self, request, pk=None):
pass
def destroy(self, request, pk=None):
pass
</code></pre>
<p>If you have ad-hoc methods that you need to be routed to, you can mark them as requiring routing using the <code>@detail_route</code> or <code>@list_route</code> decorators.</p>
<p>The <code>@detail_route</code> decorator contains <code>pk</code> in its URL pattern and is intended for methods which require a single instance. The <code>@list_route</code> decorator is intended for methods which operate on a list of objects.</p>
<p>For example:</p>
<pre><code>from django.contrib.auth.models import User
from rest_framework import status
from rest_framework import viewsets
from rest_framework.decorators import detail_route, list_route
from rest_framework.response import Response
from myapp.serializers import UserSerializer, PasswordSerializer
class UserViewSet(viewsets.ModelViewSet):
"""
A viewset that provides the standard actions
"""
queryset = User.objects.all()
serializer_class = UserSerializer
@detail_route(methods=['post'])
def set_password(self, request, pk=None):
user = self.get_object()
serializer = PasswordSerializer(data=request.data)
if serializer.is_valid():
user.set_password(serializer.data['password'])
user.save()
return Response({'status': 'password set'})
else:
return Response(serializer.errors,
status=status.HTTP_400_BAD_REQUEST)
@list_route()
def recent_users(self, request):
recent_users = User.objects.all().order('-last_login')
page = self.paginate_queryset(recent_users)
if page is not None:
serializer = self.get_serializer(page, many=True)
return self.get_paginated_response(serializer.data)
serializer = self.get_serializer(recent_users, many=True)
return Response(serializer.data)
</code></pre>
<p>The decorators can additionally take extra arguments that will be set for the routed view only. For example...</p>
<pre><code> @detail_route(methods=['post'], permission_classes=[IsAdminOrIsSelf])
def set_password(self, request, pk=None):
...
</code></pre>
<p>These decorators will route <code>GET</code> requests by default, but may also accept other HTTP methods, by using the <code>methods</code> argument. For example:</p>
<pre><code> @detail_route(methods=['post', 'delete'])
def unset_password(self, request, pk=None):
...
</code></pre>
<p>The two new actions will then be available at the urls <code>^users/{pk}/set_password/$</code> and <code>^users/{pk}/unset_password/$</code></p>
<hr />
<h1 id="api-reference"><a class="toclink" href="#api-reference">API Reference</a></h1>
<h2 id="viewset"><a class="toclink" href="#viewset">ViewSet</a></h2>
<p>The <code>ViewSet</code> class inherits from <code>APIView</code>. You can use any of the standard attributes such as <code>permission_classes</code>, <code>authentication_classes</code> in order to control the API policy on the viewset.</p>
<p>The <code>ViewSet</code> class does not provide any implementations of actions. In order to use a <code>ViewSet</code> class you'll override the class and define the action implementations explicitly.</p>
<h2 id="genericviewset"><a class="toclink" href="#genericviewset">GenericViewSet</a></h2>
<p>The <code>GenericViewSet</code> class inherits from <code>GenericAPIView</code>, and provides the default set of <code>get_object</code>, <code>get_queryset</code> methods and other generic view base behavior, but does not include any actions by default.</p>
<p>In order to use a <code>GenericViewSet</code> class you'll override the class and either mixin the required mixin classes, or define the action implementations explicitly.</p>
<h2 id="modelviewset"><a class="toclink" href="#modelviewset">ModelViewSet</a></h2>
<p>The <code>ModelViewSet</code> class inherits from <code>GenericAPIView</code> and includes implementations for various actions, by mixing in the behavior of the various mixin classes.</p>
<p>The actions provided by the <code>ModelViewSet</code> class are <code>.list()</code>, <code>.retrieve()</code>, <code>.create()</code>, <code>.update()</code>, and <code>.destroy()</code>.</p>
<h4 id="example_1"><a class="toclink" href="#example_1">Example</a></h4>
<p>Because <code>ModelViewSet</code> extends <code>GenericAPIView</code>, you'll normally need to provide at least the <code>queryset</code> and <code>serializer_class</code> attributes. For example:</p>
<pre><code>class AccountViewSet(viewsets.ModelViewSet):
"""
A simple ViewSet for viewing and editing accounts.
"""
queryset = Account.objects.all()
serializer_class = AccountSerializer
permission_classes = [IsAccountAdminOrReadOnly]
</code></pre>
<p>Note that you can use any of the standard attributes or method overrides provided by <code>GenericAPIView</code>. For example, to use a <code>ViewSet</code> that dynamically determines the queryset it should operate on, you might do something like this:</p>
<pre><code>class AccountViewSet(viewsets.ModelViewSet):
"""
A simple ViewSet for viewing and editing the accounts
associated with the user.
"""
serializer_class = AccountSerializer
permission_classes = [IsAccountAdminOrReadOnly]
def get_queryset(self):
return self.request.user.accounts.all()
</code></pre>
<p>Note however that upon removal of the <code>queryset</code> property from your <code>ViewSet</code>, any associated <a href="../routers/">router</a> will be unable to derive the base_name of your Model automatically, and so you will have to specify the <code>base_name</code> kwarg as part of your <a href="../routers/">router registration</a>.</p>
<p>Also note that although this class provides the complete set of create/list/retrieve/update/destroy actions by default, you can restrict the available operations by using the standard permission classes.</p>
<h2 id="readonlymodelviewset"><a class="toclink" href="#readonlymodelviewset">ReadOnlyModelViewSet</a></h2>
<p>The <code>ReadOnlyModelViewSet</code> class also inherits from <code>GenericAPIView</code>. As with <code>ModelViewSet</code> it also includes implementations for various actions, but unlike <code>ModelViewSet</code> only provides the 'read-only' actions, <code>.list()</code> and <code>.retrieve()</code>.</p>
<h4 id="example_2"><a class="toclink" href="#example_2">Example</a></h4>
<p>As with <code>ModelViewSet</code>, you'll normally need to provide at least the <code>queryset</code> and <code>serializer_class</code> attributes. For example:</p>
<pre><code>class AccountViewSet(viewsets.ReadOnlyModelViewSet):
"""
A simple ViewSet for viewing accounts.
"""
queryset = Account.objects.all()
serializer_class = AccountSerializer
</code></pre>
<p>Again, as with <code>ModelViewSet</code>, you can use any of the standard attributes and method overrides available to <code>GenericAPIView</code>.</p>
<h1 id="custom-viewset-base-classes"><a class="toclink" href="#custom-viewset-base-classes">Custom ViewSet base classes</a></h1>
<p>You may need to provide custom <code>ViewSet</code> classes that do not have the full set of <code>ModelViewSet</code> actions, or that customize the behavior in some other way.</p>
<h2 id="example_3"><a class="toclink" href="#example_3">Example</a></h2>
<p>To create a base viewset class that provides <code>create</code>, <code>list</code> and <code>retrieve</code> operations, inherit from <code>GenericViewSet</code>, and mixin the required actions:</p>
<pre><code>class CreateListRetrieveViewSet(mixins.CreateModelMixin,
mixins.ListModelMixin,
mixins.RetrieveModelMixin,
viewsets.GenericViewSet):
"""
A viewset that provides `retrieve`, `create`, and `list` actions.
To use it, override the class and set the `.queryset` and
`.serializer_class` attributes.
"""
pass
</code></pre>
<p>By creating your own base <code>ViewSet</code> classes, you can provide common behavior that can be reused in multiple viewsets across your API.</p>
</div> <!--/span-->
</div> <!--/row-->
</div> <!--/.fluid-container-->
</div> <!--/.body content-->
<div id="push"></div>
</div> <!--/.wrapper -->
<footer class="span12">
<p>Documentation built with <a href="http://www.mkdocs.org/">MkDocs</a>.
</p>
</footer>
<!-- Le javascript
================================================== -->
<!-- Placed at the end of the document so the pages load faster -->
<script src="../../js/jquery-1.8.1-min.js"></script>
<script src="../../js/prettify-1.0.js"></script>
<script src="../../js/bootstrap-2.1.1-min.js"></script>
<script>var base_url = '../..';</script>
<script src="../../mkdocs/js/require.js"></script>
<script src="../../js/theme.js"></script>
<script>
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/dropdown to no higher than browser window
$('.side-nav, .dropdown-menu').css('max-height', window.innerHeight - 130);
$(function() {
$(window).resize(function() {
$('.side-nav, .dropdown-menu').css('max-height', window.innerHeight - 130);
});
});
</script>
</body>
</html>