From 3c60b4b7b6a85eac9f8bd2ebf4f1a3098be04ee2 Mon Sep 17 00:00:00 2001
From: Ryan P Kilby <rpkilby@ncsu.edu>
Date: Sat, 18 Nov 2017 00:12:09 -0500
Subject: [PATCH] Add 'extra actions' to ViewSet & browsable APIs

---
 rest_framework/renderers.py                   |  7 +++
 .../templates/rest_framework/admin.html       | 14 ++++++
 .../templates/rest_framework/base.html        | 14 ++++++
 rest_framework/viewsets.py                    | 30 +++++++++++
 tests/test_renderers.py                       | 24 ++++++++-
 tests/test_viewsets.py                        | 50 +++++++++++++++++--
 6 files changed, 133 insertions(+), 6 deletions(-)

diff --git a/rest_framework/renderers.py b/rest_framework/renderers.py
index 14a371852..ca4844321 100644
--- a/rest_framework/renderers.py
+++ b/rest_framework/renderers.py
@@ -612,6 +612,11 @@ class BrowsableAPIRenderer(BaseRenderer):
     def get_breadcrumbs(self, request):
         return get_breadcrumbs(request.path, request)
 
+    def get_extra_actions(self, view):
+        if hasattr(view, 'get_extra_action_url_map'):
+            return view.get_extra_action_url_map()
+        return None
+
     def get_filter_form(self, data, view, request):
         if not hasattr(view, 'get_queryset') or not hasattr(view, 'filter_backends'):
             return
@@ -698,6 +703,8 @@ class BrowsableAPIRenderer(BaseRenderer):
             'delete_form': self.get_rendered_html_form(data, view, 'DELETE', request),
             'options_form': self.get_rendered_html_form(data, view, 'OPTIONS', request),
 
+            'extra_actions': self.get_extra_actions(view),
+
             'filter_form': self.get_filter_form(data, view, request),
 
             'raw_data_put_form': raw_data_put_form,
diff --git a/rest_framework/templates/rest_framework/admin.html b/rest_framework/templates/rest_framework/admin.html
index 4fb6480c5..faa37a586 100644
--- a/rest_framework/templates/rest_framework/admin.html
+++ b/rest_framework/templates/rest_framework/admin.html
@@ -110,6 +110,20 @@
               </form>
             {% endif %}
 
+            {% if extra_actions %}
+              <div class="dropdown" style="float: right; margin-right: 10px">
+                <button class="btn btn-default" id="extra-actions-menu" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
+                  {% trans "Extra Actions" %}
+                  <span class="caret"></span>
+                </button>
+                <ul class="dropdown-menu" aria-labelledby="extra-actions-menu">
+                  {% for action_name, url in extra_actions|items %}
+                  <li><a href="{{ url }}">{{ action_name }}</a></li>
+                  {% endfor %}
+                </ul>
+              </div>
+            {% endif %}
+
             {% if filter_form %}
               <button style="float: right; margin-right: 10px" data-toggle="modal" data-target="#filtersModal" class="btn btn-default">
                 <span class="glyphicon glyphicon-wrench" aria-hidden="true"></span>
diff --git a/rest_framework/templates/rest_framework/base.html b/rest_framework/templates/rest_framework/base.html
index fe19b5b38..eb7a96995 100644
--- a/rest_framework/templates/rest_framework/base.html
+++ b/rest_framework/templates/rest_framework/base.html
@@ -128,6 +128,20 @@
             </div>
           {% endif %}
 
+          {% if extra_actions %}
+            <div class="dropdown" style="float: right; margin-right: 10px">
+              <button class="btn btn-default" id="extra-actions-menu" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
+                {% trans "Extra Actions" %}
+                <span class="caret"></span>
+              </button>
+              <ul class="dropdown-menu" aria-labelledby="extra-actions-menu">
+                {% for action_name, url in extra_actions|items %}
+                <li><a href="{{ url }}">{{ action_name }}</a></li>
+                {% endfor %}
+              </ul>
+            </div>
+          {% endif %}
+
           {% if filter_form %}
             <button style="float: right; margin-right: 10px" data-toggle="modal" data-target="#filtersModal" class="btn btn-default">
               <span class="glyphicon glyphicon-wrench" aria-hidden="true"></span>
diff --git a/rest_framework/viewsets.py b/rest_framework/viewsets.py
index d7b2b49b7..c4cd85d0b 100644
--- a/rest_framework/viewsets.py
+++ b/rest_framework/viewsets.py
@@ -18,9 +18,11 @@ automatically.
 """
 from __future__ import unicode_literals
 
+from collections import OrderedDict
 from functools import update_wrapper
 from inspect import getmembers
 
+from django.urls import NoReverseMatch
 from django.utils.decorators import classonlymethod
 from django.views.decorators.csrf import csrf_exempt
 
@@ -159,6 +161,34 @@ class ViewSetMixin(object):
         """
         return [method for _, method in getmembers(cls, _is_extra_action)]
 
+    def get_extra_action_url_map(self):
+        """
+        Build a map of {names: urls} for the extra actions.
+
+        This method will noop if `detail` was not provided as a view initkwarg.
+        """
+        action_urls = OrderedDict()
+
+        # exit early if `detail` has not been provided
+        if self.detail is None:
+            return action_urls
+
+        # filter for the relevant extra actions
+        actions = [
+            action for action in self.get_extra_actions()
+            if action.detail == self.detail
+        ]
+
+        for action in actions:
+            try:
+                url_name = '%s-%s' % (self.basename, action.url_name)
+                url = reverse(url_name, self.args, self.kwargs, request=self.request)
+                action_urls[action.name] = url
+            except NoReverseMatch:
+                pass  # URL requires additional arguments, ignore
+
+        return action_urls
+
 
 class ViewSet(ViewSetMixin, views.APIView):
     """
diff --git a/tests/test_renderers.py b/tests/test_renderers.py
index d468398d3..6d802b1a7 100644
--- a/tests/test_renderers.py
+++ b/tests/test_renderers.py
@@ -16,16 +16,19 @@ from django.utils.translation import ugettext_lazy as _
 
 from rest_framework import permissions, serializers, status
 from rest_framework.compat import coreapi
+from rest_framework.decorators import action
 from rest_framework.renderers import (
     AdminRenderer, BaseRenderer, BrowsableAPIRenderer, DocumentationRenderer,
     HTMLFormRenderer, JSONRenderer, SchemaJSRenderer, StaticHTMLRenderer
 )
 from rest_framework.request import Request
 from rest_framework.response import Response
+from rest_framework.routers import SimpleRouter
 from rest_framework.settings import api_settings
-from rest_framework.test import APIRequestFactory
+from rest_framework.test import APIRequestFactory, URLPatternsTestCase
 from rest_framework.utils import json
 from rest_framework.views import APIView
+from rest_framework.viewsets import ViewSet
 
 DUMMYSTATUS = status.HTTP_200_OK
 DUMMYCONTENT = 'dummycontent'
@@ -622,7 +625,18 @@ class StaticHTMLRendererTests(TestCase):
         assert result == '500 Internal Server Error'
 
 
-class BrowsableAPIRendererTests(TestCase):
+class BrowsableAPIRendererTests(URLPatternsTestCase):
+    class ExampleViewSet(ViewSet):
+        def list(self, request):
+            return Response()
+
+        @action(detail=False, name="Extra list action")
+        def list_action(self, request):
+            raise NotImplementedError
+
+    router = SimpleRouter()
+    router.register('examples', ExampleViewSet, base_name='example')
+    urlpatterns = [url(r'^api/', include(router.urls))]
 
     def setUp(self):
         self.renderer = BrowsableAPIRenderer()
@@ -640,6 +654,12 @@ class BrowsableAPIRendererTests(TestCase):
                                                view=DummyView(), request={})
         assert result is None
 
+    def test_extra_actions_dropdown(self):
+        resp = self.client.get('/api/examples/', HTTP_ACCEPT='text/html')
+        assert 'id="extra-actions-menu"' in resp.content.decode('utf-8')
+        assert '/api/examples/list_action/' in resp.content.decode('utf-8')
+        assert '>Extra list action<' in resp.content.decode('utf-8')
+
 
 class AdminRendererTests(TestCase):
 
diff --git a/tests/test_viewsets.py b/tests/test_viewsets.py
index d5c428e3a..f3e85050e 100644
--- a/tests/test_viewsets.py
+++ b/tests/test_viewsets.py
@@ -1,3 +1,5 @@
+from collections import OrderedDict
+
 import pytest
 from django.conf.urls import include, url
 from django.db import models
@@ -35,10 +37,10 @@ class ActionViewSet(GenericViewSet):
     queryset = Action.objects.all()
 
     def list(self, request, *args, **kwargs):
-        raise NotImplementedError
+        return Response()
 
     def retrieve(self, request, *args, **kwargs):
-        raise NotImplementedError
+        return Response()
 
     @action(detail=False)
     def list_action(self, request, *args, **kwargs):
@@ -56,6 +58,10 @@ class ActionViewSet(GenericViewSet):
     def custom_detail_action(self, request, *args, **kwargs):
         raise NotImplementedError
 
+    @action(detail=True, url_path=r'unresolvable/(?P<arg>\w+)', url_name='unresolvable')
+    def unresolvable_detail_action(self, request, *args, **kwargs):
+        raise NotImplementedError
+
 
 router = SimpleRouter()
 router.register(r'actions', ActionViewSet)
@@ -121,16 +127,52 @@ class InitializeViewSetsTestCase(TestCase):
             self.assertIn(attribute, dir(view))
 
 
-class GetExtraActionTests(TestCase):
+class GetExtraActionsTests(TestCase):
 
     def test_extra_actions(self):
         view = ActionViewSet()
         actual = [action.__name__ for action in view.get_extra_actions()]
-        expected = ['custom_detail_action', 'custom_list_action', 'detail_action', 'list_action']
+        expected = [
+            'custom_detail_action',
+            'custom_list_action',
+            'detail_action',
+            'list_action',
+            'unresolvable_detail_action',
+        ]
 
         self.assertEqual(actual, expected)
 
 
+@override_settings(ROOT_URLCONF='tests.test_viewsets')
+class GetExtraActionUrlMapTests(TestCase):
+
+    def test_list_view(self):
+        response = self.client.get('/api/actions/')
+        view = response.renderer_context['view']
+
+        expected = OrderedDict([
+            ('Custom list action', 'http://testserver/api/actions/custom_list_action/'),
+            ('List action', 'http://testserver/api/actions/list_action/'),
+        ])
+
+        self.assertEqual(view.get_extra_action_url_map(), expected)
+
+    def test_detail_view(self):
+        response = self.client.get('/api/actions/1/')
+        view = response.renderer_context['view']
+
+        expected = OrderedDict([
+            ('Custom detail action', 'http://testserver/api/actions/1/custom_detail_action/'),
+            ('Detail action', 'http://testserver/api/actions/1/detail_action/'),
+            # "Unresolvable detail action" excluded, since it's not resolvable
+        ])
+
+        self.assertEqual(view.get_extra_action_url_map(), expected)
+
+    def test_uninitialized_view(self):
+        self.assertEqual(ActionViewSet().get_extra_action_url_map(), OrderedDict())
+
+
 @override_settings(ROOT_URLCONF='tests.test_viewsets')
 class ReverseActionTests(TestCase):
     def test_default_basename(self):