Use of Django’s built-in generic views vs single function using something like @api_view([‘GET’, ‘PUT’, ‘DELETE’])

he choice between using separate classes for create, delete, and other actions, or combining them into a single function using something like @api_view(['GET', 'PUT', 'DELETE']), depends on a few factors such as code organization, reusability, and the use of Django’s built-in generic views.

Here’s why separate classes are often preferred in Django REST Framework (DRF) projects:

1. Use of DRF’s Generic Views:

Django REST Framework provides generic views like ListCreateAPIView and DestroyAPIView to handle common patterns (listing, creating, deleting, etc.) in a standard way. These views:

• Provide built-in logic to handle common HTTP methods (GET, POST, DELETE, etc.).
• Use a standard pattern that makes code more maintainable and less repetitive.

By separating concerns (like list/create and delete), each class does one thing and adheres to the Single Responsibility Principle.

Example:

• ListCreateAPIView handles GET (listing) and POST (creating).
• DestroyAPIView handles DELETE requests.

2. Reusability:

When you separate the logic into different classes (like NoteListCreate and NoteDelete), it makes it easier to reuse them. If you need to use the same logic elsewhere (e.g., in a different view or project), you can simply import the respective view class and use it.

• NoteListCreate can be used when you want to allow listing and creating notes.
• NoteDelete can be reused when you only need the delete functionality elsewhere.

3. Better Alignment with REST Principles:

REST principles advocate separating actions into individual endpoints. This means that typically:

• GET (list), POST (create), PUT (update), and DELETE should have their own respective views (or at least separate logic in the view).
• This helps make the code more explicit and easier to debug.

4. Built-in Permissions and Throttling:

Using separate view classes for different actions gives you better control over permissions and throttling. For example:

• You might allow any authenticated user to create a note (permission_classes = [IsAuthenticated] for NoteListCreate).
• You could enforce stricter permissions for delete actions (like allowing only the owner of the note to delete it).

With the function-based view approach (@api_view(['GET', 'PUT', 'DELETE'])), managing different permissions or throttle rates for different actions within the same view becomes more complex and less maintainable.

5. Maintainability and Readability:

• By splitting views into separate classes, each class is focused on a specific responsibility, which enhances code readability.
• It’s easier to debug or modify a single view class for creating notes (NoteListCreate) than to have all actions combined in one function.

Example: When to Use Function-based Views (FBVs):

• Function-based views like @api_view are useful for simple cases where combining actions makes sense (e.g., when handling a single resource like a “snippet”).
• They can be good for small projects or when you need fine control over every action without relying on the generic logic of class-based views.

Example of Combining Actions in a Function-Based View:

from rest_framework.decorators import api_view
from rest_framework.response import Response
from rest_framework import status
from .models import Snippet
from .serializers import SnippetSerializer

@api_view(['GET', 'PUT', 'DELETE'])
def snippet_detail(request, pk):
    try:
        snippet = Snippet.objects.get(pk=pk)
    except Snippet.DoesNotExist:
        return Response(status=status.HTTP_404_NOT_FOUND)

    if request.method == 'GET':
        serializer = SnippetSerializer(snippet)
        return Response(serializer.data)

    elif request.method == 'PUT':
        serializer = SnippetSerializer(snippet, data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

    elif request.method == 'DELETE':
        snippet.delete()
        return Response(status=status.HTTP_204_NO_CONTENT)

This can work well, but as your project grows, it can become harder to manage, especially with more complex views or when you need to apply different permissions or authentication settings.