Default value for custom input object type

I have a custom input object type

class Filters(graphene.InputObjectType):                                        
    name = graphene.String()
    type = graphene.List(graphene.String)

and the query definition

class Query(graphene.ObjectType):                                               
    search = graphene.Field(
        SearchResult, query=graphene.String(required=True),
        filters=graphene.Argument(Filters, default_value=None)
    )

I want to be able to provide an empty default value for the filters argument. With the above definition, the argument is not set as optional and I’m getting this error message:

{
  "errors": [
    {
      "message": "resolve_search() missing 1 required positional argument: 'filters'",
      "locations": [
        {
          "line": 15,
          "column": 3
        }
      ],
      "path": [
        "search"
      ]
    }
  ],
  "data": {
    "search": null
  }
}

What is the correct way to provide an empty default value for the argument of custom object type? I’m at these package versions:

graphene==2.1.3 graphql-core==2.1 graphql-server-core==1.1.1

[artemnesterenko]

For now, I’ve ended up with the following solution:

import graphene

class InputObjectType(graphene.InputObjectType):

    @classmethod
    def default(cls):
        meta = cls._meta
        fields = meta.fields
        default_fields = {name: field.default_value for name, field in fields.items()}
        container = meta.container
        return container(**default_fields)


class SizeInput(InputObjectType):
    width = graphene.Int(default_value=100)
    height = graphene.Int(default_value=100)

    def square(self):
        return self.width * self.height

Since now, it’s possible to do:

class Query(graphene.ObjectType):
    square = graphene.Field(
        graphene.NonNull(graphene.Int),
        size=graphene.Argument(SizeInput, default_value=SizeInput.default())
    )
    
    @staticmethod
    def resolve_square(root, info, size, **kwargs):
        return size.square()

It produces the correct schema and passes the default value I was expecting instead of the empty dict.

[patrick91]

Yeah using Filters() should work, so I guess there’s a bug somewhere 😃

I’ll see if I can have a look at it soon