What are Django REST Framework viewsets and routers?

Question

Accepted Answer

**ViewSets** group related views. **Routers** auto-generate URL patterns.

```python
from rest_framework import viewsets, status
from rest_framework.decorators import action
from rest_framework.response import Response
from .models import User
from .serializers import UserSerializer

# ViewSet — CRUD in one class
class UserViewSet(viewsets.ModelViewSet):
    queryset = User.objects.all()
    serializer_class = UserSerializer

# Custom action
    @action(detail=False, methods=["get"])
    def me(self, request):
        serializer = self.get_serializer(request.user)
        return Response(serializer.data)

@action(detail=True, methods=["post"])
    def follow(self, request, pk=None):
        user_to_follow = self.get_object()
        request.user.following.add(user_to_follow)
        return Response({"status": "followed"})

# Router — auto URL generation
from rest_framework.routers import DefaultRouter

router = DefaultRouter()
router.register(r"users", UserViewSet)
router.register(r"posts", PostViewSet)

# Generated URLs:
# GET    /users/           — list
# POST   /users/           — create
# GET    /users/{id}/      — retrieve
# PUT    /users/{id}/      — update
# PATCH  /users/{id}/      — partial update
# DELETE /users/{id}/      — destroy
# GET    /users/me/        — custom action
# POST   /users/{id}/follow/ — custom action

# In urls.py
urlpatterns = [
    path("", include(router.urls)),
]

# ReadOnlyViewSet — only list and retrieve
class TagViewSet(viewsets.ReadOnlyModelViewSet):
    queryset = Tag.objects.all()
    serializer_class = TagSerializer
```

**ViewSet actions:**
- `list` — GET all.
- `create` — POST.
- `retrieve` — GET one.
- `update` — PUT.
- `destroy` — DELETE.

Python: What are Django REST Framework viewsets and routers?