Different types with the same name in the schema - Django fields with choices

[kozickikarol]

Hi,

When you try to create a model with choices field and then create a second model which inherit from the previous one, you will receive error while schema generating.

Here you have a simple project with models and basic configuration. Try to generate schema and you will get following error:

AssertionError: Found different types with the same name in the schema: PageType, PageType.

It seems that it is unable to inherit models with choices fields.

[ncrmro]

Getting same

AssertionError: Found different types with the same name in the schema: PartMarketState, PartMarketState.

This is using django-fsm (functional state machine) which is guess creates set of enums as well

[fangaofeng]

I getting a same error.
File "E:\pythonvenv\django11\lib\site-packages\graphql\type\definition.py", line 180, in fields
return define_field_map(self, self._fields)
File "E:\pythonvenv\django11\lib\site-packages\graphql\type\definition.py", line 189, in define_field_map
field_map = field_map()
File "E:\pythonvenv\django11\lib\site-packages\graphene\types\typemap.py", line 235, in construct_fields_for_type
map = self.reducer(map, field.type)
File "E:\pythonvenv\django11\lib\site-packages\graphene\types\typemap.py", line 72, in reducer
return self.graphene_reducer(map, type)
File "E:\pythonvenv\django11\lib\site-packages\graphene\types\typemap.py", line 77, in graphene_reducer
return self.reducer(map, type.of_type)
File "E:\pythonvenv\django11\lib\site-packages\graphene\types\typemap.py", line 72, in reducer
return self.graphene_reducer(map, type)
File "E:\pythonvenv\django11\lib\site-packages\graphene\types\typemap.py", line 83, in graphene_reducer
).format(_type.graphene_type, type)
AssertionError: Found different types with the same name in the schema: UserUserType, UserUserType.

class User(BDAbstractUser):

    TYPE_CHOICES = [('agent', 'agent'), ('nomal', 'nomal.'), ('superuser',
     """                                                          'superuser')]
    user_type = models.CharField(max_length=10, blank=True)
    """
    user_type = models.CharField(
        _('user type'),
        max_length=10,
        choices=TYPE_CHOICES,
        default='nomal',
        help_text=_('need user type'))

[Tyrdall]

It seems you're not allowed to include type in your field's name. I tried type = models.CharField() and foo_type = models.CharField() and both caused that error.

When I changed the field's name to foo the error was gone.

[alexche8]

Still have this issue after renaming of models fields.
But this hack works for me #87 (comment)

[darkowic]

Is it documented anywhere that we can not use field name type in models when using this library?

[sanfilippopablo]

@darkowic I was wondering why I was getting this error. Now that you mention, the problematic model has a type field in it.

[NathanLawrence]

This is quite a glaring bug to still have.

What can be done about it? Thoughts?

[denis-ryzhkov]

When graphene_django converts a field with choices to graphene.Enum, it creates a new type for this field.

If it was type field of model Foo, new autogenerated type will be FooType.

And you probably already have your own

class FooType(DjangoObjectType):
     class Meta:
         model = Foo

So there is AssertionError: Found different types with the same name in the schema: FooType, FooType.

This conversion raised a lot of questions already: https://github.com/graphql-python/graphene-django/issues?q=is%3Aissue+choices

Maybe someone adds GRAPHENE_CONVERT_CHOICES_TO_ENUMS = False setting to graphene_django once.

Until then I am going to monkey-patch it somewhere before schema is imported, for example in settings file.

Patch: https://gist.github.com/denis-ryzhkov/fcb944f6ebfad4775efb74848703f0d7

[jkimbo]

@denis-ryzhkov thanks for the investigation! You're right, the issues seems to be that the auto naming of the Enum field that a Django choice field gets converted to is likely to clash with an existing type in your schema since it's just the object type name plus the field name:

graphene-django/graphene_django/converter.py

Line 50 in a480a39

name = to_camel_case('{}_{}'.format(meta.object_name, field.name))

I think the fix for that is make the generated name more explicit and less likely to clash with anything in the schema. Something like DjangoModel{object_name}{field_name}Choices (e.g. DjangoModelFooTypeChoices).

Separately, disabling the conversion of Django choice fields to Enums is a good idea since it's not always desired. Though I think it's probably something that should be done on a field level rather than globally.

[bastiW]

I fixed it by just using the import statement. I imported the type from another class instead of rewriting it again.

But that maybe does not solve the issues if you overwrite a class

[GasimGasimzada]

I have also had this issue and @denis-ryzhkov explanation helped me resolve the issue. I have a model Organization with field type with choices in it. For schema I had the following:

class OrganizationType(DjangoObjectType):
    class Meta:
        model = Organization

As a result, I was getting:

AssertionError: Found different types with the same name in the schema: OrganizationType, OrganizationType.

After reading through this, I just changed the class name to OrganizationGQLType. Now, everyhing works as expected. If this decision is not going to be changed, I think it would be beneficial to add this to the docs to clear out the confusion.

[aindong]

I also encountered the same error and renaming the field type into something fixed my problem