from rest_framework.views import APIView

→ APIView is a base class provided by DRF that allows you to define views like a typical class but with REST functionality (GET, POST, PUT, etc.).

from rest_framework.response import Response

→ Response is used to return structured API responses in JSON format.

from rest_framework import status

→ DRF provides HTTP status codes like 200 OK, 201 CREATED, 400 BAD REQUEST using status.

from .models import Book

→ Importing the Book model to work with the database.

from .serializers import BookSerializer

→ Importing the BookSerializer so we can convert model data into JSON format.

Custom View Class:

class CustomBookCreateView(APIView):

→ This class is a custom view to handle POST requests. It extends from APIView.

def get(self, request, *args, **kwargs):

→ This method handles GET requests to retrieve all books from the database.
→ request: Represents the HTTP request made by the client.
→ *args, **kwargs: These are used to handle any additional arguments (e.g., filtering options).

Fetching All Books:

books = Book.objects.all()

→ This fetches all records from the Book model (i.e., retrieves all books stored in the database).

Serializing the Data:

serializer = BookSerializer(books, many=True)

→ BookSerializer(books, many=True) converts the books queryset into JSON format.
→ many=True is required because we are serializing multiple objects (a list of books).

Returning the Response:

return Response(serializer.data)

→ This sends back the serialized book data as a JSON response.
→ The client (frontend or API consumer) will receive a structured list of books in JSON format.

def post(self, request):

→ This method will be executed when a POST request hits this view URL.

Extracting Data from Request:

title = request.data.get(‘title’)

author = request.data.get(‘author’)

price = request.data.get(‘price’)

published_date = request.data.get(‘published_date’)

→ We’re manually accessing each field from the incoming request data (which is usually in JSON format).

Manual Validation:

if not title or not author:

    return Response({‘error’: ‘Title and author are required.’}, status=status.HTTP_400_BAD_REQUEST)

→ Basic validation: If either title or author is missing, return an error message with 400 Bad Request.

Creating the Book Record:

book = Book.objects.create(

    title=title,

    author=author,

    price=price,

    published_date=published_date

)

→ This line creates a new record in the database using the extracted data.

Serializing the Record and Returning Response:

serializer = BookSerializer(book)

→ After creating the book, we serialize it so that it can be returned as JSON.

Return Response(serializer.data, status=status.HTTP_201_CREATED)

→ We return the serialized data with status 201 Created indicating success.