Interface implementation object types are not exposed on schema when not used by any field

[sikanhe]

Interface implementation object types are not exposed on schema when not used by any field

[sikanhe]

I thought interface already have resolveType
https://github.com/sikanhe/gqtx/blob/master/src/types.ts#L157
https://github.com/sikanhe/gqtx/blob/master/src/define.ts#L215

Alternatively, I think the better way for interface implementation should be using isTypeOf on the subtypes

Quote from graphql creator Lee Byron on this issue:
graphql/graphql-js#876 (comment)

[n1ru4l]

I thought interface already have resolveType
https://github.com/sikanhe/gqtx/blob/master/src/types.ts#L157
https://github.com/sikanhe/gqtx/blob/master/src/define.ts#L215

There is no option for defining the resolveType function with the define API with the interfaceType function:

gqtx/src/define.ts

Lines 224 to 242 in 460bcee

	interfaceType<Src>({
	name,
	description,
	fields,
	}: {
	name: string;
	description?: string;
	fields: (self: Interface<Ctx, Src | null>) => Array<AbstractField<Ctx, any>>;
	}): Interface<Ctx, Src | null> {
	const obj: Interface<Ctx, Src | null> = {
	kind: 'Interface',
	name,
	description,
	fieldsFn: undefined as any,
	};
	obj.fieldsFn = () => fields(obj) as any;
	return obj;
	},

Alternatively, I think the better way for interface implementation should be using isTypeOf on the subtypes

I never heard of that API actually. Looks interesting. and I will definitely check it out. Still, for completeness we should probably still provide the resolveType function option for the interfaceType function.

Unless I have no field that "consumes" the type GraphQLUserChatMessageType or GraphQLOperationalChatMessageType the both types are not available on the GraphQL Schema.

Any ideas on how we can tackle this? Sometimes I only have a field that returns an interface type but the interface implementation types are not directly returned by any field.

A workaround would be to add dummy fields to the Query/Mutation type that return null.

A more clean and clever solution would allow passing in those object types via the buildGraphQLSchema function.

The API could look something like this:

import { buildGraphQLSchema } from "gqtx";
// ... other imports

export const schema = buildGraphQLSchema({
  query: Query,
  subscription: Subscription,
  mutation: Mutation,
  additionalObjectTypes: {
    GraphQLDiceRollOperatorNode,
    GraphQLDiceRollConstantNode,
    GraphQLDiceRollDiceRollNode,
    GraphQLDiceRollOpenParenNode,
    GraphQLDiceRollCloseParenNode,
  }
});

An even more convenient way would be to auto-detect those types by reading the types from unionTypes(Edit: This is already happening right now). This does not work for interface types though.

Therefore the explicit way of passing them to the buildGraphQLSchema function could be the better solution.

[n1ru4l]

I will create a new issue for union types and isTypeOf typing improvements