Support for Proxy Models

[jm2242]

Is there support for querying proxy models? I'm trying to query a model that has a bunch of proxy models but am getting an error. Here's an abbreviated look at my setup:

class Column:
...

class FieldColumn(Column):
  proxy=True

class Query(graphene.ObjecType):
    column = graphene.Field(ColumnType)
    all_columns = DjangoFilterConnectionField(ColumnType)

and

class ColumnType(DjangoObjectType):
    class Meta:
        model = Column
        filter_fields = ['sheet__name', 'name']
        interfaces = (relay.Node, )
        exclude_fields = [  
            'legislation_type', 'project_stat_type', ... # weirdly have to exclude these fields because the 'type' in the variable name makes the field introspector sad
        ]

my query is:

query {
	allColumns(sheet_Name:"Simple Sheet") {
		edges {
      node{
        id, name
      }
    }
  }
}

Here's the trace:

Traceback (most recent call last):
  File "/Users/jonathanmares/.virtualenvs/quorum/lib/python2.7/site-packages/promise/promise.py", line 65, in try_catch
    return (handler(*args, **kwargs), None)
  File "/Users/jonathanmares/.virtualenvs/quorum/lib/python2.7/site-packages/graphql/execution/executor.py", line 375, in <lambda>
    resolved
  File "/Users/jonathanmares/.virtualenvs/quorum/lib/python2.7/site-packages/graphql/execution/executor.py", line 405, in complete_value
    return complete_object_value(exe_context, return_type, field_asts, info, result)
  File "/Users/jonathanmares/.virtualenvs/quorum/lib/python2.7/site-packages/graphql/execution/executor.py", line 499, in complete_object_value
    field_asts
graphql.error.base.GraphQLError: Expected value of type "ColumnType" but got: FieldColumn.

I know this PR https://github.com/graphql-python/graphene-django/pull/156/files is waiting to be merged, but I tried running my query with the proposed changes and still get the same error.

[spockNinja]

Following that traceback, I think the root of the problem is here.

We are checking for _meta.model to match between the actual returned object and the model assigned in the DjangoObjectType meta.

So I think to support proxy models, we might want to check _meta.model._meta.concrete_model instead? I'm not sure on the django version support for concrete_model, but if it has always been there, that just might work. Otherwise, we might have to check _meta.model._meta.proxy and handle that case specially.

[spockNinja]

I went back through django source to 1.7, and it looks like concrete_model has always been there. Would you like to whip up a Pull Request with that change and see if it solves the problem for you?

[jm2242]

excellent! that was it, thanks for your help. I'll get a PR up with a test or two and some docs

[serates]

@jm2242 Did you get this PR up? If so could you link it here so i could follow it since my issue should also be fixed by this PR.

[jm2242]

I have not, but I will do this today or tomorrow!

[filipeximenes]

Did this get fixed? Is there a temporary solution to it?

[jm2242]

Yes I believe this PR does address this, at least basic support #373

[filipeximenes]

@jm2242 thanks for getting back. I just noticed that it was failing for me because I was trying to use it in model relationship and at the model level I was defining the relationship through the proxy model. So if someone finds this, just make sure you don't use proxy models in the ForeignKeys of your models.
Not super urgent, but should we treat this as bug? As in, should graphene know how to handle this case?

[jm2242]

Maybe post a minimal example, and someone can pick it up and fix it?

[filipeximenes]

A bit late but the example would be:

class Model1(models.Model):
     ....

class ProxyModel1(Model1):
    ....
    class Meta:
        proxy = True

class Model2(models.Model):
    relationship = models.ForeignKey(ProxyModel1)
    ....

[zbyte64]

The test case currently has an Article that has a foreign key to a proxy model Reporter

Currently at:

graphene-django/graphene_django/tests/test_query.py

Line 896 in ea2cd98

def test_proxy_model_support():

To match the example given here they foreign key would be adjusted to CNNReporter