title: Django REST Framework combining routers from different apps
body: <p>I have a project that spans multiple apps:</p>
  
  <pre><code>./project/app1
  ./project/app2
  ./project/...
  </code></pre>
  
  <p>Each app has a router for Django REST Framework to incorporate the parts of the API provided by that app:</p>
  
  <pre><code>from django.conf.urls import url, include
  from rest_framework.routers import DefaultRouter
  from .views import ThingViewSet
  
  router = DefaultRouter()
  router.register(r'things', ThingViewSet, base_name='thing')
  
  urlpatterns = [
      url(r'^', include(router.urls)),
  ]
  </code></pre>
  
  <p>Because the apps are separate, my top-level URLs file (<code>./project/urls.py</code>) includes each of the URLs files from the separate apps:</p>
  
  <pre><code>url(r'^api/app1/', include('app1.urls', namespace='a1')),
  url(r'^api/app2/', include('app2.urls', namespace='a2')),
  </code></pre>
  
  <p>This means that Django REST Framework shows a separate API root for each app. What I would like, however, is a unified API structure, so that if I navigate to <code>http://example.com/api/</code> I see the full list of all URLs that are available at that level of the hierarchy.</p>
  
  <p>I presume there is a way to include all my separate routers defined in the individual <code>urls.py</code> files for each app into a single router, but I can't find documentation on how to do this. Am I missing something obvious?</p>