django_rest_url_with_query_paramaters

serializers.py

class BookCoverSerializer(serializers.HyperlinkedModelSerializer):

    class Meta:
        model = Book
        fields = ('cover',)

    def validate(self, attrs):
        attrs = super().validate(attrs)
        book = Book.objects.get(pk=self.context['book_id'])
        attrs['book'] = book
        return attrs

    def create(self, validated_data):
        book = validated_data.get('book')
        book.cover = validated_data.get('cover')
        print(book.cover)
        book.save()
        return book