Usage RESTfull API

[lafemmeduviking]

Hello,

I'm trying to use your module with the django rest framework but when I'm creating my entity from a serializer I loose the EAV fields.
Is there any way I can make it work?

Everything works fine from the admin.

thanks for your help

[Dresdn]

Since the model itself is registered, any usage should inherit the EAV fields. Have any code or anything to share?

[lafemmeduviking]

This is my patterbn model :

class Pattern(models.Model):
name = models.CharField(max_length=200, blank=False, null=True)
creator = models.ForeignKey(Creator,
on_delete=models.DO_NOTHING,
blank=True,
null=True,
related_name="creator", default=None)
# category = models.CharField(max_length=100, blank=True, null=True)
# gender = models.CharField(max_length=100, blank=True, null=True)
# format = models.CharField(max_length=100, blank=True, null=True)
size = models.CharField(max_length=50, blank=True, null=True)
level = models.DecimalField(max_digits=2, decimal_places=1, blank=True, default=None, null=True)
is_published = models.BooleanField(default=False)

His advanced registration :

class PatternEavConfig(EavConfig):
manager_attr = 'objects'
manager_only = False
eav_attr = 'eav'
generic_relation_attr = 'eav_values'
generic_relation_related_name = None

@classmethod
def get_attributes(cls, instance=None):
    entity = ContentType.objects.filter(model='pattern').values('id')
    return Attribute.objects.filter(entity_ct=entity[0]["id"])

This the pattern serializer:

class PatternPostSerializer(serializers.ModelSerializer):
"""Pattern creation serializer with material / without images """
creator = serializers.PrimaryKeyRelatedField(queryset=Creator.objects.all())
attributes = AttributeSerializer(many=True, required=False)

class Meta:
    model = Pattern
    fields = ('id', 'name', 'creator', 'attributes', 'size', 'level')

def get_creator(self, object):
    print('object creator: ', object)
    if object.creator is None:
        return None
    else:
        return Creator.objects.filter(id=object.creator_id).values('id', 'name')

def get_attributes(self, object):
    return object.eav_values.all().values('value_enum_id', 'value_enum_value', 'attribute_slug')

def to_representation(self, instance):
    """Set field type for output only"""
    self.fields["creator"] = serializers.SerializerMethodField()
    self.fields["attributes"] = serializers.SerializerMethodField()
    return super().to_representation(instance)

def create(self, validated_data):
    attributes = []
    if 'attributes' in validated_data:
        attributes = validated_data.pop('attributes')
        print('attributes', attributes)

    pattern_instance = Pattern.objects.create(**validated_data)

    for attribute in attributes:
        if attribute:
            Value.objects.create(entity=pattern_instance,
            #                              entity_ct_id=21,
                                 attribute=attribute['attribute'],
                                 value_enum=attribute['value_enum'])
    return pattern_instance

The attributes serializer :

class AttributeSerializer(serializers.ModelSerializer):
class Meta:
model = Value
fields = ['attribute', 'value_enum']

POST example:

Thanks a lot

[Dresdn]

Thanks for sharing as that helps provide some context. One thing to note, you didn't specify what the actual error message/problem you were having, so I'm going to have guess some.

Focusing on the serializer, it seems like you're trying to manually create a Value object based on the attribute data passed in. This seems like a lot of effort and probably where you're seeing a problem since there's a lot of underlying relationships that the Manager creates for you.

I would say there's 2 paths to take:

1. If you want to pass in the FK id's, then take a look at how Entity.save_value() handles this.
2. Alternatively, you use the IDs to get the Attribute by the id and then do a setattr(entity, attribute.slug, value) with a instance.save() at the end

Here's how you could do it based on your code:

def create(self, validated_data):
  attributes = validated_data.pop('attributes', None)
  
  pattern_instance = Pattern(**validated_data)
  # Get the Entity for the instance
  entity = pattern_instance.eav

  for attribute in attributes:
    attr = instance.get_all_attributes().get(id=attribute[attribute]) # You'll want to wrap this in a try in case the Attribute isn't associated with the Entity
    # Code to handle the enum e.g. value = attr.enum_group.values.get(pk=attribute[value_enum])
    setattr(entity, attr.slug, value)

  # Save the object like normal and let the eav manager do it's thing on creating the Value objects
  pattern_instance.save() # wrap in a try to return any validation errors

[lafemmeduviking]

Thanks a lot for your help ! It works fine.

I had no error, just no new attribute for my entity pattern.