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Django 4.1 - Issues with Serializing Nested Serializer with Dynamic Fields Based on Request

👀 Views: 837 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-05
django django-rest-framework serializers Python

I'm wondering if anyone has experience with I'm trying to implement I'm following best practices but After trying multiple solutions online, I still can't figure this out... I'm working with Django REST Framework (DRF) and I've run into an issue when trying to serialize nested serializers with dynamic fields. I have a `Post` model that contains multiple `Comment` instances as a related field. Depending on the user's permissions, I want to include or exclude certain fields in the `CommentSerializer`. Here's what my serializers look like: ```python class CommentSerializer(serializers.ModelSerializer): class Meta: model = Comment fields = ['id', 'content', 'created_at', 'author'] # 'author' should be dynamic based on user permissions class PostSerializer(serializers.ModelSerializer): comments = CommentSerializer(many=True, read_only=True) class Meta: model = Post fields = ['id', 'title', 'comments'] ``` In my view, I'm trying to modify the fields of the `CommentSerializer` based on whether the user has permission to view the 'author' field: ```python class PostDetailView(APIView): def get(self, request, pk): post = get_object_or_404(Post, pk=pk) serializer = PostSerializer(post, context={'request': request}) return Response(serializer.data) ``` I attempted to modify the `CommentSerializer` to adjust its fields based on the context, like so: ```python class CommentSerializer(serializers.ModelSerializer): class Meta: model = Comment fields = ['id', 'content', 'created_at'] # Default fields def __init__(self, *args, **kwargs): user = kwargs.pop('user', None) super().__init__(*args, **kwargs) if user and user.has_perm('view_author'): self.fields['author'] = serializers.CharField(source='author.username') # Add 'author' field ``` But when I try to access the `PostDetailView`, I get a `TypeError` that says `__init__() got an unexpected keyword argument 'user'`. I've ensured that the view passes the request context correctly. Any ideas on how I can properly pass the user to the `CommentSerializer` so it can dynamically adjust the fields? This is the error message I'm getting: ``` TypeError: __init__() got an unexpected keyword argument 'user' ``` I am using Django 4.1 with Django REST Framework 3.12. Help would be greatly appreciated! My development environment is Windows. Is there a simpler solution I'm overlooking? Is there a simpler solution I'm overlooking? My team is using Python for this service. What's the correct way to implement this?