django-rest-framework/api-guide/metadata/index.html
2019-12-12 14:50:50 +00:00

603 lines
23 KiB
HTML

<!DOCTYPE html>
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta charset="utf-8">
<title>Metadata - Django REST framework</title>
<link href="../../img/favicon.ico" rel="icon" type="image/x-icon">
<link rel="canonical" href="https://www.django-rest-framework.org/api-guide/metadata/" />
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="description" content="Django, API, REST, Metadata">
<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>
#sidebarInclude img {
margin-bottom: 10px;
}
#sidebarInclude a.promo {
color: black;
}
@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/encode/django-rest-framework/tree/master">GitHub</a>
<a class="repo-link btn btn-inverse btn-small " rel="next" href="../schemas/">
Next <i class="icon-arrow-right icon-white"></i>
</a>
<a class="repo-link btn btn-inverse btn-small " rel="prev" href="../content-negotiation/">
<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="https://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 >
<a href="../viewsets/">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="../caching/">Caching</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 class="active" >
<a href="./">Metadata</a>
</li>
<li >
<a href="../schemas/">Schemas</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/api-clients/">API Clients</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>
</ul>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">Community <b class="caret"></b></a>
<ul class="dropdown-menu">
<li >
<a href="../../community/tutorials-and-resources/">Tutorials and Resources</a>
</li>
<li >
<a href="../../community/third-party-packages/">Third Party Packages</a>
</li>
<li >
<a href="../../community/contributing/">Contributing to REST framework</a>
</li>
<li >
<a href="../../community/project-management/">Project management</a>
</li>
<li >
<a href="../../community/release-notes/">Release Notes</a>
</li>
<li >
<a href="../../community/3.11-announcement/">3.11 Announcement</a>
</li>
<li >
<a href="../../community/3.10-announcement/">3.10 Announcement</a>
</li>
<li >
<a href="../../community/3.9-announcement/">3.9 Announcement</a>
</li>
<li >
<a href="../../community/3.8-announcement/">3.8 Announcement</a>
</li>
<li >
<a href="../../community/3.7-announcement/">3.7 Announcement</a>
</li>
<li >
<a href="../../community/3.6-announcement/">3.6 Announcement</a>
</li>
<li >
<a href="../../community/3.5-announcement/">3.5 Announcement</a>
</li>
<li >
<a href="../../community/3.4-announcement/">3.4 Announcement</a>
</li>
<li >
<a href="../../community/3.3-announcement/">3.3 Announcement</a>
</li>
<li >
<a href="../../community/3.2-announcement/">3.2 Announcement</a>
</li>
<li >
<a href="../../community/3.1-announcement/">3.1 Announcement</a>
</li>
<li >
<a href="../../community/3.0-announcement/">3.0 Announcement</a>
</li>
<li >
<a href="../../community/kickstarter-announcement/">Kickstarter Announcement</a>
</li>
<li >
<a href="../../community/mozilla-grant/">Mozilla Grant</a>
</li>
<li >
<a href="../../community/funding/">Funding</a>
</li>
<li >
<a href="../../community/jobs/">Jobs</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="#metadata">Metadata</a>
</li>
<li>
<a href="#setting-the-metadata-scheme">Setting the metadata scheme</a>
</li>
<li>
<a href="#creating-schema-endpoints">Creating schema endpoints</a>
</li>
<li class="main">
<a href="#custom-metadata-classes">Custom metadata classes</a>
</li>
<li>
<a href="#example">Example</a>
</li>
<li class="main">
<a href="#third-party-packages">Third party packages</a>
</li>
<li>
<a href="#drf-schema-adapter">DRF-schema-adapter</a>
</li>
<div class="promo">
<hr/>
<div id="sidebarInclude">
</div>
</ul>
</div>
</div>
<div id="main-content" class="span9">
<a class="github" href="https://github.com/encode/django-rest-framework/tree/master/rest_framework/metadata.py">
<span class="label label-info">metadata.py</span>
</a>
<h1 id="metadata"><a class="toclink" href="#metadata">Metadata</a></h1>
<blockquote>
<p>[The <code>OPTIONS</code>] method allows a client to determine the options and/or requirements associated with a resource, or the capabilities of a server, without implying a resource action or initiating a resource retrieval.</p>
<p>&mdash; <a href="https://tools.ietf.org/html/rfc7231#section-4.3.7">RFC7231, Section 4.3.7.</a></p>
</blockquote>
<p>REST framework includes a configurable mechanism for determining how your API should respond to <code>OPTIONS</code> requests. This allows you to return API schema or other resource information.</p>
<p>There are not currently any widely adopted conventions for exactly what style of response should be returned for HTTP <code>OPTIONS</code> requests, so we provide an ad-hoc style that returns some useful information.</p>
<p>Here's an example response that demonstrates the information that is returned by default.</p>
<pre><code>HTTP 200 OK
Allow: GET, POST, HEAD, OPTIONS
Content-Type: application/json
{
"name": "To Do List",
"description": "List existing 'To Do' items, or create a new item.",
"renders": [
"application/json",
"text/html"
],
"parses": [
"application/json",
"application/x-www-form-urlencoded",
"multipart/form-data"
],
"actions": {
"POST": {
"note": {
"type": "string",
"required": false,
"read_only": false,
"label": "title",
"max_length": 100
}
}
}
}
</code></pre>
<h2 id="setting-the-metadata-scheme"><a class="toclink" href="#setting-the-metadata-scheme">Setting the metadata scheme</a></h2>
<p>You can set the metadata class globally using the <code>'DEFAULT_METADATA_CLASS'</code> settings key:</p>
<pre><code>REST_FRAMEWORK = {
'DEFAULT_METADATA_CLASS': 'rest_framework.metadata.SimpleMetadata'
}
</code></pre>
<p>Or you can set the metadata class individually for a view:</p>
<pre><code>class APIRoot(APIView):
metadata_class = APIRootMetadata
def get(self, request, format=None):
return Response({
...
})
</code></pre>
<p>The REST framework package only includes a single metadata class implementation, named <code>SimpleMetadata</code>. If you want to use an alternative style you'll need to implement a custom metadata class.</p>
<h2 id="creating-schema-endpoints"><a class="toclink" href="#creating-schema-endpoints">Creating schema endpoints</a></h2>
<p>If you have specific requirements for creating schema endpoints that are accessed with regular <code>GET</code> requests, you might consider re-using the metadata API for doing so.</p>
<p>For example, the following additional route could be used on a viewset to provide a linkable schema endpoint.</p>
<pre><code>@action(methods=['GET'], detail=False)
def schema(self, request):
meta = self.metadata_class()
data = meta.determine_metadata(request, self)
return Response(data)
</code></pre>
<p>There are a couple of reasons that you might choose to take this approach, including that <code>OPTIONS</code> responses <a href="https://www.mnot.net/blog/2012/10/29/NO_OPTIONS">are not cacheable</a>.</p>
<hr />
<h1 id="custom-metadata-classes"><a class="toclink" href="#custom-metadata-classes">Custom metadata classes</a></h1>
<p>If you want to provide a custom metadata class you should override <code>BaseMetadata</code> and implement the <code>determine_metadata(self, request, view)</code> method.</p>
<p>Useful things that you might want to do could include returning schema information, using a format such as <a href="https://json-schema.org/">JSON schema</a>, or returning debug information to admin users.</p>
<h2 id="example"><a class="toclink" href="#example">Example</a></h2>
<p>The following class could be used to limit the information that is returned to <code>OPTIONS</code> requests.</p>
<pre><code>class MinimalMetadata(BaseMetadata):
"""
Don't include field and other information for `OPTIONS` requests.
Just return the name and description.
"""
def determine_metadata(self, request, view):
return {
'name': view.get_view_name(),
'description': view.get_view_description()
}
</code></pre>
<p>Then configure your settings to use this custom class:</p>
<pre><code>REST_FRAMEWORK = {
'DEFAULT_METADATA_CLASS': 'myproject.apps.core.MinimalMetadata'
}
</code></pre>
<h1 id="third-party-packages"><a class="toclink" href="#third-party-packages">Third party packages</a></h1>
<p>The following third party packages provide additional metadata implementations.</p>
<h2 id="drf-schema-adapter"><a class="toclink" href="#drf-schema-adapter">DRF-schema-adapter</a></h2>
<p><a href="https://github.com/drf-forms/drf-schema-adapter">drf-schema-adapter</a> is a set of tools that makes it easier to provide schema information to frontend frameworks and libraries. It provides a metadata mixin as well as 2 metadata classes and several adapters suitable to generate <a href="https://json-schema.org/">json-schema</a> as well as schema information readable by various libraries.</p>
<p>You can also write your own adapter to work with your specific frontend.
If you wish to do so, it also provides an exporter that can export those schema information to json files.</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 async src="https://fund.django-rest-framework.org/sidebar_include.js"></script>
<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 src="../../js/theme.js"></script>
<script>var base_url = '../..';</script>
<script src="../../search/main.js" defer></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>