Get value of another field in Field level Validation in DRF

I dug around codebase of drf a little bit. You can get values of all fields using following approach. This way you can throw serialization error as {'my_field':'error message} instead of {'non_field_error':'error message'}

def validate_myfield(self, value):
   data = self.get_initial() # data for all the fields
   #do your validation

However, if you wish to do it for ListSerializer, i.e for serializer = serializer_class(many=True), this won't work. You will get list of empty values. In that scenario, you could write your validations in def validate function and to avoid non_field_errors in your serialization error, you can raise ValidationError with error message as a dictionary instead of string.

def validate(self, data):
    # do your validation
    raise serializers.ValidationError({"your_field": "error_message"})

No that is not possible. If you need to access more than one value you have to use the Object-level validation (see docs):

class Keys_Serializer(serializers.Serializer):

    key_id = serializers.IntegerField(required=True)
    key_name = serializers.CharField(required=True)
    value_id = serializers.IntegerField(required=False)

    def validate(self, data):
        # here you can access all values
        key_id = data['key_id']
        value_id = data['value_id']
        # perform you validation
        if key_id != value_id:
            raise serializers.ValidationError("key_id must be equal to value_id")
        return data