Django rest framework (ModelViewSet): insert a parameter before save.

[Sidon]

I am looking a way for insert a parameter in a data serializer before save, I have a model with only 2 fields, for stay easy, let's consider that both are of an API service on the internet, like twitter. For example.

I have to accept a command line, via curl, like this:

curl -X POST -F twitter_id=1399 http://localhost:8000/api/users/, then to consult the api service and, finally, save on my database.

My problem is: There is just one parameter (twitter_id) on the query, how to insert a second parameter (twitter_name)?

Below I show my code and my try (commented)

model:

    class User(models.Model):

        twitter_id

        twitter_name 

view.py:

    class UserViewSet(viewsets.ModelViewSet):

        serializer_class = UserSerializer

        queryset = User.objects.all()

        def get_queryset(self):

            queryset = User.objects.all()

            twt_id = self.request.query_params.get('twitter_id', None)

            limit = self.request.query_params.get('limit', None)

    

            if tw_id is not None:

                queryset = queryset.filter(twitter_id=tw_id)

            elif limit is not None:        

                queryset = queryset[:int(limit)]

            return queryset

    

serializer.py

    class UserSerializer(serializers.ModelSerializer):

        links = serializers.SerializerMethodField()

        data_twt = {}

        

        class Meta:

            model = user

            fields = ('twitter_id', 'twitter_name')

    

         # ... 

   

        def get_links(self, obj):

            request = self.context['request']

            links = {'self': reverse('person-detail', kwargs={'pk': obj.pk}, request=request)}

        def validate(self, data):

            if bool(self.context['request'].POST):

                tw_id = str(data['twitter_id'])

                _tw_id = User.objects.filter(twitter_id=fb_id)

                if _tw_id.exists():

                    raise serializers.ValidationError('User already registered')

                else:

                    try:

                        self.data_twt = get_twitter_person(fb_id)

                        # Here I tried to modify data, but data is read only

                        # data['twitter_name'] = self.data_twt['name']

                    except:

                        raise serializers.ValidationError('Id not in Twitter')

            return data

[Sidon]

Ok, Finally, I solve my issue: In UserViewSet:

    def perform_create(self, serializer):
        serializer.save(twitter_name='Blah Blah'