How to correctly use third-party GraphQL schema object types

[tony-oldport]

I'm using a library graphql-geojson that defines a number of GraphQL schema object types based on the GeoJSON spec.

I thought (probably naively) that I may just be able to import these and use them as a Field type, but I get the CannotDetermineGraphQLTypeError: Cannot determine GraphQL output type error.

The error only seems to happen when I use one of the GraphQLObjectType like MultiPolygonObject. No problems when I try one of the GraphQLScalarType like CoordinatesScalar

I've also tried adding the types to orphanedTypes with no luck.

import { Field, ObjectType } from 'type-graphql'
import { MultiPolygonObject } from 'graphql-geojson'

@ObjectType()
export class Zone {
  @Field(type => MultiPolygonObject, { nullable: true })
    multiPolygon?: any
}

[MichalLytek]

AFAIR TypeGraphQL does not cooperate with graphql-js types. You would need to redeclare those types with decorators, maybe this tool can help you:
https://the-guild.dev/graphql/codegen/plugins/typescript/typescript-type-graphql

The support could be easily added, but I don't have throughput for that for now 😕

[tony-oldport]

Ahh, gotcha. Appreciate it as always.