Expand Schema Tags script

The code in this repository is experimental and has been provided for reference purposes only. Community feedback is welcome but this project may not be supported in the same way that repositories in the official Apollo GraphQL GitHub organization are. If you need help you can file an issue on this repository, contact Apollo to talk to an expert, or create a ticket directly in Apollo Studio.

This script allows tagging all elements of a schema by adding a tag to the schema definition itself.

extend schema @tag(name: "put-this-everywhere")

type Query {
  foo: String
}

type Bar {
  id: ID!
}

cat myschema.graphql \
  | npx github:@apollosolutions/expand-schema-tags \
  | rover subgraph publish --name products --schema -

type Query {
  foo: String @tag(name: "put-this-everywhere")
}

type Bar {
  id: ID! @tag(name: "put-this-everywhere")
}

Additionally, you can provide the --apply-inheritance flag to apply inheritance rules:

type Bar @tag(name: "public") {
  id: ID!
  baz: String
  quux: String
}

cat myschema.graphql \
  | npx github:@apollosolutions/expand-schema-tags --apply-inheritance

type Bar {
  id: ID! @tag(name: "public")
  baz: String @tag(name: "public")
  quux: String @tag(name: "public")
}

Notes

• Inspired by our friends at Wayfair. ❤️
• If the script detects the Federation 2 @link directive, it will tag enum values and input type fields.
• Tags fields and not types/interfaces. Tagging a type can affect fields in other subgraphs due to post-composition tag inheritance.
• Does not add tags to @external fields because that's invalid in Federation 2.