Django REST Framework - Using Nested Serializers with Create and Update Methods
I'm having a hard time understanding I've been struggling with this for a few days now and could really use some help. I'm working on a project and hit a roadblock. I'm stuck on something that should probably be simple. Hey everyone, I'm running into an issue that's driving me crazy... I'm working on a Django application using Django REST Framework (version 3.12.4) and I'm having trouble with nested serializers. Specifically, I'm trying to create and update a model with related data using nested serializers, but I'm running into an issue where the child objects are not being created or updated properly. Here's a simplified version of my models: ```python class Author(models.Model): name = models.CharField(max_length=100) class Book(models.Model): title = models.CharField(max_length=200) author = models.ForeignKey(Author, related_name='books', on_delete=models.CASCADE) ``` And here are my serializers: ```python class AuthorSerializer(serializers.ModelSerializer): class Meta: model = Author fields = ['id', 'name'] class BookSerializer(serializers.ModelSerializer): author = AuthorSerializer() class Meta: model = Book fields = ['id', 'title', 'author'] def create(self, validated_data): author_data = validated_data.pop('author') author, created = Author.objects.get_or_create(**author_data) book = Book.objects.create(author=author, **validated_data) return book def update(self, instance, validated_data): author_data = validated_data.pop('author') instance.title = validated_data.get('title', instance.title) instance.save() author, created = Author.objects.get_or_create(**author_data) instance.author = author instance.save() return instance ``` When I send a POST request to create a new book with author data like this: ```json { "title": "New Book", "author": { "name": "John Doe" } } ``` It works fine, and the book and author are created. However, when I attempt to send a PATCH request to update the book's title and author name: ```json { "title": "Updated Book", "author": { "name": "Jane Doe" } } ``` I receive a 400 Bad Request error with the message: `"{'author': [ErrorDetail(string='This field is required.', code='required')]}`. It seems like the author data isn't being processed correctly during the update. I've tried adding validation checks to ensure the author data is not empty, but I still encounter this issue. I'd appreciate any insights on how to properly handle updates for nested serializers in Django REST Framework. Is there something I might be missing in the update method? My development environment is Ubuntu. Am I missing something obvious? Thanks in advance! What's the best practice here? The stack includes Python and several other technologies. I'd be grateful for any help. I'd really appreciate any guidance on this. Am I approaching this the right way? I'm working with Python in a Docker container on macOS. I appreciate any insights!