Challenge 2: Build a Full CRUD API — Possible Solution
====================================================================

# catalog/serializers.py

from rest_framework import serializers
from .models import Author

class AuthorSerializer(serializers.ModelSerializer):
    class Meta:
        model = Author
        fields = ["id", "name", "bio"]

# catalog/views.py

from rest_framework import viewsets
from .models import Author
from .serializers import AuthorSerializer

class AuthorViewSet(viewsets.ModelViewSet):
    queryset = Author.objects.all()
    serializer_class = AuthorSerializer

# catalog/urls.py

from rest_framework.routers import DefaultRouter
from .views import AuthorViewSet

router = DefaultRouter()
router.register("authors", AuthorViewSet)

urlpatterns = router.urls

# mysite/urls.py (the project's root, per Course 1 Chapter 2's include() pattern)

from django.urls import path, include

urlpatterns = [
    path("api/", include("catalog.urls")),
]

RESULTING ROUTES (mounted under /api/ from the project root)
------------------------------------------------------------------
  GET    /api/authors/       -> list all authors
  POST   /api/authors/       -> create a new author
  GET    /api/authors/{id}/  -> retrieve one author
  PUT    /api/authors/{id}/  -> update one author (full replace)
  PATCH  /api/authors/{id}/  -> partially update one author
  DELETE /api/authors/{id}/  -> delete one author

WHY THIS WORKS
--------------
- AuthorViewSet only needs two class attributes — queryset (which rows)
  and serializer_class (how to shape them) — and ModelViewSet's parent
  class implements every one of the six actions above using those two
  pieces of information; nothing else needed to be written by hand.
- router.register("authors", AuthorViewSet) is the single line that
  replaces what would otherwise be five or six separate path() entries
  in urlpatterns, one per action — directly mirroring the chapter's
  comparison to Rails' resources :books generating multiple routes from
  one declaration.
- Mounting catalog.urls under "api/" in the project's root urls.py
  reuses the exact include() pattern from Course 1, Chapter 2 — the app's
  own urls.py (in this case, router.urls) never needs to know or care
  what prefix it ends up served under.