Graphene-django: Allow fragments for models with inheritance

[nhydock]

The library appears to currently be lacking the ability to use fragments when using models that have subclasses.

__models.py__

class MyModel(models.Model):
    name = models.CharField(max_length=50)

class ModelA(MyModel):
    extra = models.IntegerField()

class ModelB(MyModel):
    text = models.TextField()

__fields.py__

class ModelType(DjangoObjectType):
    class Meta:
        model = MyModel

class ModelAType(DjangoObjectType):
    class Meta:
        model = ModelA

class ModelBType(DjangoObjectType):
    class Meta:
        model = ModelB

__query__

query {
    all_models {
        __typename,
        name,
        ... on ModelAType {
            extra
        },
        ... on ModelBType {
            text
        }
    }
}

Suggestion: Modify DjangoObjectType to also act like a Union, or create a DjangoUnionType, with the ability to resolve type based on subclass and using the registered type for the subclass if applicable.

[japrogramer]

Create a class that inherits from graphene.types.union.Union
than in the meta class of that class have all the types you want to union.

class MyUnion(graphene.types.union.Union):
    class Meta:
        types = (ModelType, ModelAType, ModelBType)

class ModelQuery(graphene.ObjectType):
    some = graphene.Field(graphene.List(MyUnion), variable=graphene.Argument(graphene.String, required=True))
    def resolve_some(self, args, context, info):
        # do whatever to retrieve your models, in a list
        model = [ ...]
        amodel = [...]
        bmodel = [...]
        return model + amodel + bmodel

[MichaelrMentele]

@japrogramer When I do the above, the type checks for each of those unioned models resolves to the root type or abstract type, at least when using django-typed-models and then graphene complains that I have multiple models of the same type.

[cfarvidson]

Any new progress on this? I’m also getting this error when using Django polymorphic.

[mvanlonden]

No progress as of yet. PRs welcome

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[japrogramer]

Im not using multiple inheritance
but i am inheriting from the abstract models.Model.
and have no errors.

it seems that where Union
is imported from changed.

class TimeLineDataType(graphene.Union):
    class Meta:
        types = (PostType, CommentType, ShareType, PinType)

class ActivityType(graphene.ObjectType):
    name = 'ActivityType'
    subject = graphene.Field(TimeLineDataType)

    def resolve_subject(self, info):
        return self

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.