@apollo/federation-internals/src/specs/cacheTagSpec.ts

Apollo Federation internal utilities

// This `cacheTag` spec is a supergraph-only feature spec to indicate that some of the subgraphs
// use the `@cacheTag` directive. The `@cacheTag` directive itself is not used in supergraph
// schema, since `@cacheTag` directive applications are composed using the `@join__directive`
// directive.
import {
  CorePurpose,
  FeatureDefinition,
  FeatureDefinitions,
  FeatureUrl,
  FeatureVersion,
} from "./coreSpec";

export const CACHE_TAG = 'cacheTag';

export class CacheTagSpecDefinition extends FeatureDefinition {
  public static readonly specName = CACHE_TAG;
  public static readonly identity = `https://specs.apollo.dev/${CacheTagSpecDefinition.specName}`;

  constructor(version: FeatureVersion, minimumFederationVersion?: FeatureVersion) {
    super(
      new FeatureUrl(
        CacheTagSpecDefinition.identity,
        CacheTagSpecDefinition.specName,
        version
      ),
      minimumFederationVersion,
    );
  }

  get defaultCorePurpose(): CorePurpose {
    return 'EXECUTION';
  }
}

export const CACHE_TAG_VERSIONS =
  new FeatureDefinitions<CacheTagSpecDefinition>(
    CacheTagSpecDefinition.identity
  ).add(
    new CacheTagSpecDefinition(new FeatureVersion(0, 1)),
  );