facebook/relay · error

Not Implemented

Error message

Not Implemented

What it means

getDefaultActorIdentifier in the multi-actor-environment API is intentionally unimplemented; the module only provides utilities to build/split actor identifiers. Calling this method throws 'Not Implemented' — multi-actor environments require you to supply your own actor-identifier resolution.

Source

Thrown at packages/relay-runtime/multi-actor-environment/ActorIdentifier.js:39

const INTERNAL_ACTOR_IDENTIFIER_DO_NOT_USE: ActorIdentifier =
  'INTERNAL_ACTOR_IDENTIFIER_DO_NOT_USE';

function assertInternalActorIdentifier(actorIdentifier: ActorIdentifier): void {
  invariant(
    actorIdentifier === INTERNAL_ACTOR_IDENTIFIER_DO_NOT_USE,
    'Expected to use only internal version of the `actorIdentifier`. "%s" was provided.',
    actorIdentifier,
  );
}

module.exports = {
  INTERNAL_ACTOR_IDENTIFIER_DO_NOT_USE,
  assertInternalActorIdentifier,
  getActorIdentifier(actorID: string): ActorIdentifier {
    return actorID as ActorIdentifier;
  },
  getDefaultActorIdentifier(): ActorIdentifier {
    throw new Error('Not Implemented');
  },
};

View on GitHub (pinned to 668b1b85e0)

Solutions

1. Provide your own actor identifier resolution when constructing the multi-actor environment instead of calling getDefaultActorIdentifier
2. Only call getActorIdentifier(actorID) to construct explicit actor identifiers, or use assertInternalActorIdentifier for internal ids
3. Avoid multi-actor APIs if you don't need them; use a standard RelayModernEnvironment

Example fix

// before
const id = env.getDefaultActorIdentifier();
// after
const id = getActorIdentifier('user:123'); // build an explicit ActorIdentifier

if (typeof env.getDefaultActorIdentifier === 'function') {
  // multi-actor default resolution is not implemented; never call it
  throw new Error('Provide explicit actor identifiers via getActorIdentifier(actorID)');
}

try {
  env.getDefaultActorIdentifier();
} catch (e) {
  if (e.message === 'Not Implemented') {
    // fall back to an explicit actor id derived from your session
  }
}

When it happens

Trigger: Calling MultiActorEnvironment's default actor resolution path, i.e. using a multi-actor setup (getActorIdentifier / actor-conditional queries) without providing a custom default actor identifier implementation.

Common situations: Adopting the experimental multi-actor-environment API (e.g. per-actor GraphQL fragments in fed-style schemas) and relying on the default implementation instead of overriding actor identification.

AI-assisted analysis of facebook/relay@668b1b85e0 (2026-09-02). Data as JSON: /api/errors/a30eb9d5d1a88bf5. Report an issue: GitHub.