Represent json data with PrimaryKeyRelatedField in django - django

Question

I'm designing a mailbox with Django. My code is as follows:
#models.py
class Post(models.Model):
text = models.CharField(max_length=256)
sender = models.ForeignKey(User)
receiver = models.ForeignKey(User)
class Comment(models.Model):
post = models.ForeignKey(Post)
text = models.CharField(max_length=256)
#serializers.py
class CommentSerializer(serializers.ModelSerializer):
post = serializers.PrimaryKeyRelatedField()
class Meta:
model = Comment
fields = [
'id',
'text',
'post'
]
class PostSerializer(serializers.ModelSerializer):
class Meta:
model = Post
fields = [
'id',
'text',
'sender',
'receiver',
]
class MainUserSerializer(serializers.ModelSerializer):
class Meta:
model = User
fields = ['username', 'email']
I tried to customize serializer and have a serializer as follows:
class PostSerializer(serializers.Field):
def to_representation(self, value):
return PostSerializer(value, context={'request': self.context['request']}).data
def to_internal_value(self, id):
try:
id = int(id)
except ValueError:
raise serializers.ValidationError("Id should be int.")
try:
post = Post.objects.get(pk=id)
except User.DoesNotExist:
raise serializers.ValidationError("Such a post does not exist")
return user
I want to represent comment objects like this
{
"post":{
"text" = "Hello"
"sender" = 1
"receiver" = 2
}
"text": "Greate"
}
My code works great but The problem is it doesn't show the Combo Box for selecting the post. I also tried to customize the PrimaryKeyRelatedField's to_represent method in this way:
class PostSerializer(serializers.PrimaryKeyRelatedField):
def to_representation(self, value):
post_id = super(PostSerializer, self).to_representation(value)
post = Post.objects.get(pk=user_id)
return PostSerializer(
user, {"context":self.context['request']}
).data
but it says the unhashable type: 'ReturnDict' and as I understand we could return anything but simple things such as int or string. Is there a way to do this?