RocketChat/Rocket.Chat · error · Meteor.Error

error-federated-users-in-non-federated-rooms

error-federated-users-in-non-federated-rooms

Error message

Cannot add federated users to non-federated rooms

What it means

createRoom refuses to add federated members (usernames containing '@' and ':', the Matrix-style identifier shape) unless the room is explicitly marked federated (extraData.federated === true). This guard prevents accidentally mixing remote users into a purely local room.

Source

Thrown at apps/meteor/server/lib/rooms/createRoom.ts:168

	options?: ICreateRoomParams['options'],
): Promise<
	ICreatedRoom & {
		rid: string;
	}
> => {
	const { teamId, ...extraData } = roomExtraData || ({} as IRoom);

	// TODO: use a shared helper to check whether a user is federated
	const hasFederatedMembers = members.some((member) => {
		if (typeof member === 'string') {
			return member.includes(':') && member.includes('@');
		}
		return member.username?.includes(':') && member.username?.includes('@');
	});

	// Prevent adding federated users to rooms that are not marked as federated explicitly
	if (hasFederatedMembers && extraData.federated !== true) {
		throw new Meteor.Error('error-federated-users-in-non-federated-rooms', 'Cannot add federated users to non-federated rooms', {
			method: 'createRoom',
		});
	}

	await prepareCreateRoomCallback.run({
		type,
		// name,
		// owner: ownerUsername,
		// members,
		// readOnly,
		extraData,
		// options,
	});

	const shouldBeHandledByFederation = extraData.federated === true;

	if (shouldBeHandledByFederation && owner && !isUserNativeFederated(owner) && !(await FederationMatrix.canUserAccessFederation(owner))) {
		throw new Meteor.Error('error-not-authorized-federation', 'Not authorized to access federation', {

View on GitHub (pinned to b2c16d5842)

Solutions

1. Pass federated: true in roomExtraData when any member is a federated user
2. Filter federated usernames out of members when creating a local-only room
3. Validate member usernames before calling createRoom and fail early with a clear message

Example fix

// before
createRoom('c', name, owner, ['alice', 'bob:matrix.org@remote'], {});

// after
createRoom('c', name, owner, ['alice', 'bob:matrix.org@remote'], { federated: true });

const FEDERATED_RE = /[:@]/;
const membersAreFederated = members.some(m =>
  typeof m === 'string' ? FEDERATED_RE.test(m) : Boolean(m.username && m.includes(':') && m.includes('@'))
);
if (membersAreFederated && extraData?.federated !== true) {
  extraData = { ...extraData, federated: true };
}

const isFederatedUsername = (username: string): boolean => username.includes(':') && username.includes('@');

try {
  await createRoom(type, name, owner, members, extraData);
} catch (err) {
  if (err instanceof Meteor.Error && err.error === 'error-federated-users-in-non-federated-rooms') {
    // decide: drop federated members OR set extraData.federated = true and retry
  }
  throw err;
}

When it happens

Trigger: Calling createRoom (type other than 'd') with a members array containing a string like 'user:server.tld@external-host' or a user object whose username contains ':' and '@', while roomExtraData is omitted or federated is not exactly true.

Common situations: Apps or REST/API callers copying a member list that includes federated usernames but forgetting { federated: true } in roomExtraData; federation recently enabled and existing automation reusing old payloads; string vs boolean coercion bugs where federated is passed as 'true' or 1.

Related errors

• error-invalid-members
• error-creator-not-in-room
• error-invalid-room
• error-federated-users-in-non-federated-rooms
• Federated user not found locally

AI-assisted analysis of RocketChat/Rocket.Chat@b2c16d5842 (2026-08-18). Data as JSON: /api/errors/e61b99046ff53994. Report an issue: GitHub.