CODEWITHSUNDEEP
djangodjango-rest-framework
Shashishekhar Hasabnis
Shashishekhar Hasabnis

Reputation: 1756

Overridden create method not saving the instance field in Django Rest Framework

I am working with the nested serializers in my project. There is just one small problem that I am facing and unable to guess whats going wrong.

I have two models:-
Model 1:-

class Answer_Options(models.Model):
    text = models.CharField(max_length=200)

Model 2:-

class Quiz_Question(models.Model):
    text = models.CharField(max_length=200)
    possible_answers = models.ManyToManyField(Answer_Options)
    correct = models.ForeignKey(Answer_Options, related_name="correct", default=None, on_delete=models.CASCADE, blank=True, null=True)

I have created the following serializers for my above models as follows:-

class Answer_OptionsSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Answer_Options
        fields = ('url', 'text')

And for Quiz Question:-

class Quiz_QuestionSerializer(serializers.HyperlinkedModelSerializer):
    possible_answers = Answer_OptionsSerializer(many=True)
    correct = Answer_OptionsSerializer()
    class Meta:
        model = Quiz_Question
        fields = ('url', 'text', 'possible_answers', 'correct')

    def create(self, validated_data):
        possible_answers_data = validated_data.pop('possible_answers')
        correct_answers_data = validated_data.pop('correct')
        quiz_question = Quiz_Question.objects.create(**validated_data)
        if possible_answers_data:
            for answer in possible_answers_data:
                answer, created  = Answer_Options.objects.get_or_create(text=answer['text'])     
                if (answer.text == correct_answers_data['text']):
                    quiz_question.correct = answer     //Not sure why this is not getting saved                          
                quiz_question.possible_answers.add(answer)
        return quiz_question

What happens is that when I post data through Django Rest Framework the create method gets called and possible answers get saved but don't know why the correct answer is not getting save for that instance.


I am not getting any error or exception. Also I can see the correct answer on the Django Rest Frameworks new object created page. But when I click the details page for that object I see null value for the correct answer.
Any clue of what I am doing wrong?

The sample json data that I am posting is like:-

{
    "text": "Google Headquarters are in?",
    "possible_answers": [
       {
            "text": "USA"
        },
        {
            "text": "Nort Korea"
        },
        {
            "text": "China"
        },
        {
            "text": "India"
        }
],
    "correct": {
        "text": "USA"
    }
}

Upvotes: 0

Views: 334

Answers (1)

neverwalkaloner
neverwalkaloner

Reputation: 47354

You need to call save() after changed correct value:

def create(self, validated_data):
    possible_answers_data = validated_data.pop('possible_answers')
    correct_answers_data = validated_data.pop('correct')
    quiz_question = Quiz_Question.objects.create(**validated_data)
    if possible_answers_data:
        for answer in possible_answers_data:
            answer, created  = Answer_Options.objects.get_or_create(text=answer['text'])    
            if answer.text == correct_answers_data['text']:
                quiz_question.correct = answer   
                quiz_question.save() # save changes
            quiz_question.possible_answers.add(answer)
    return quiz_question

Upvotes: 2

Related Questions