How to extend a type without a key

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,
1

Hello everyone,
So this is not really a studio specific enquiry, I’ve a specific use case in mind.

So the thing I’m trying to accomplish is to publish a type which can be queried by anyone and this type simply gives you information about the API itself. What I want to do is introduce type called maybe ApiInfo, and each subgraph adds themself as a field and exposes their own information, I’d invision my type (when combined into supergraph) would look something like:

type ApiInfo {
  accounts {
    version: String!
  }
  payments {
    version: String!
  }
  cart {
    version: String!
  }
}

So that when debugging, we know which version of subgraph composes our supergraph schema. (Ignore the invalid syntax, you get the idea),

One way to do would be to add a id inside anyway and mark that as ID, but that kinda looks ugly, is that the only way? Or can I just extend without using the key?

Thanks in advance

2

Would it be easier to return custom headers for every request to the child service?

That way, if a query touches a specific service you can have a header for each version.

Alternatively, yes, you could make this type, but you’d likely need to stub it out somewhere, such as:

type ApiInfo {
  _unused: String
}

# Accounts service
extend type ApiInfo {
  accounts: AccountsApiInfo!
}

type AccountsApiInfo {
  version: String!
}

I don’t think you’d need to use @key or @external, because these objects have no foreign key relationship.

3

Thanks @kevin-lindsay-1 , this is definitely awesome, btw, is there a way to use managed federation, but add 1 resolver to the gateway which is exposed? I was thinking, ApiInfo itself would be exposed from Gateway, and it’d have it’s own version (we do version our gateway), and I could expose that,

Is there some docs on how to let gateway expose certain resolvers?

4

I’ve never tried adding resolvers directly to the gateway, and I’m not sure if there’s any docs for that use case.

I think a more supported option would be to have a special service that handles that type. Headers sound easier, though.