Add @specifiedBy directive

[m14t]

Description

This in an implementation for a spec proposal:

• Spec proposal: [RFC] Custom Scalar Specification URIs
• Original issue: [RFC] Custom Scalar Specification URIs

Example usage

Source

const { graphql, buildSchema } = require("graphql");

const schema = buildSchema(`
  """
  A UUID
  """
  scalar UUID @specified(by: "https://tools.ietf.org/html/rfc4122")
  
  type Query {
    someUUID: UUID
  }
`);

const root = {
  someUUID: () => {
    return "750fce86-fc2f-4b25-a7df-fd0941d3fa08";
  }
};

const query = `
{
  __type(name: "UUID") {
    kind
    name
    description
    specifiedBy
  }
}`;

graphql(schema, query, root).then(response => {
  console.log(JSON.stringify(response, null, 4));
});

Output

{
    "data": {
        "__type": {
            "kind": "SCALAR",
            "name": "UUID",
            "description": "A UUID",
            "specifiedBy": "https://tools.ietf.org/html/rfc4122"
        }
    }
}

Notes

Please let me know if I forgot something.

[m14t]

@IvanGoncharov Thanks for the review!

While trying to improve the test coverage here, I wanted pass an SDL that used @specified to cycleSDL, but ran into #2020.

I'm not entirely sure of the implications of this, but if more work is need and given some direction, I'd be happy to continue to work on this.

cc: @eapache

[eapache]

I can't speak to the question about schema printer but the rest of this LGTM.

Thanks for the help Matt!

[IvanGoncharov]

While trying to improve the test coverage here, I wanted pass an SDL that used @Specified to cycleSDL, but ran into #2020.

@m14t It should be handled the same way as @deprecate.
#2020 is about printing user-provided directives and there is nothing wrong in hardcoding standard directives for a time being.
Also please review tests that mention @deprecate or deprecatedReason and replicate ones that make sense for @specified/specifiedBy.

[m14t]

@IvanGoncharov thank you for the feedback.

I've made the requested changes, and feel better about this. I still need to check that I have all of the test cases, but think that the implementation is done.

[IvanGoncharov]

I still need to check that I have all of the test cases, but think that the implementation is done.

@m14t You should have 100% coverage for diff ATM it's 97.56%:

[IvanGoncharov]

@m14t Can please update this PR to be in sync with graphql/graphql-spec@b418b60 ?

[m14t]

@IvanGoncharov Sorry for the delay here, but this is ready for another review when you have a chance.

[IvanGoncharov]

@m14t Sorry for the delay will try to review, merge, release before tomorrow's WG.

[mjmahone]

This is technically a breaking change: code that was using IntrospectionScalarType no longer type-checks unless specifiedByUrl is explicitly set.