Current implementation of federation does not conform to the Apollo Federation subgraph specification

[newerbie]

What happened?

There are several issues in federation implementation according to the Apollo Federation subgraph specification:

1. When customizing root query type, _service is not generated in customized query struct. Then Apollo gateway cannot get service definition in subgraph.
2. If @key directive is not used in graphql schema, both _service and _entities are not generated.

What did you expect?

1. _service is generated in customized query struct.
2. _service is generated in any case, while _entities is generated only when @key directive exists.

Minimal graphql.schema and models to reproduce

schema {
    query: CustomQuery
}

type Hello {
  name: String!
}

type CustomQuery {
  hello: Hello!
}

versions

• gqlgen version 0.15.1
• go version 1.17
• dep or go modules? go modules

[ipfans]

@StevenACoffman Please review this and help us fix it.