Problem with POST from fronside. Method does not support writable dotted-source fields by default

Question

I create some dotted source field in my serializer. I did it cause have to display name value of foreign key not pk value. But when I trying to POST from frontend djang throws this : AssertionError at /api/my-api/ The .create() method does not support writable dotted-source fields by default. Write an explicit .create() method for serializer MySerializer, or set read_only=True on dotted-source serializer fields.

So, when I set read_only = True my POST from frontend to request null for every field from dotted-source serializer fields.

This is my serializer:

class FcaWorksSerializer(serializers.ModelSerializer):
    fell_form = serializers.CharField(source="fell_form.name" )
    #...
    main_type = serializers.CharField(source="main_type.name")

    class Meta:
        model = FcaWorks
        fields = ('id_fca','wkod', 'main_type','fell_form','fell_type','kind',\
        'sortiment','vol_drew','use_type','fca_res','ed_izm','vol_les','act_name',\
        'obj_type','use_area','indicator','comment','date_report')

How I can to solve this problem?

Answer 1

Override the __init__() method of the serializer to adjust the serializer condition

class FcaWorksSerializer(serializers.ModelSerializer):
    fell_form = serializers.CharField()
    # ...
    main_type = serializers.CharField()

    class Meta:
        model = FcaWorks
        fields = ('id_fca', 'wkod', 'main_type', 'fell_form', 'fell_type', 'kind',
                  'sortiment', 'vol_drew', 'use_type', 'fca_res', 'ed_izm', 'vol_les', 'act_name',
                  'obj_type', 'use_area', 'indicator', 'comment', 'date_report')

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        if self.context['request'].method == 'GET':
            self.fields['fell_form'].source = "fell_form.name"
            self.fields['main_type'].source = "main_type.name"

    def create(self, validated_data):
        # here you will get the data
        fell_form = validated_data['fell_form']
        main_type = validated_data['main_type']