remotion-dev/remotion · error

Expected current user ID

Error message

Expected current user ID

What it means

After validating invokedFunctionArn, routine extracts the AWS account ID as the 5th colon-separated segment of the ARN (split(':')[4]) to use as the expected bucket owner. If the ARN is malformed or that segment is empty, this error is thrown. It protects against S3 bucket-owner misconfiguration.

Source

Thrown at packages/lambda/src/functions/index.ts:47

	const buffered =
		params.type === ServerlessRoutines.info ||
		params.type === ServerlessRoutines.start ||
		params.type === ServerlessRoutines.compositions;

	try {
		process.env.__RESERVED_IS_INSIDE_REMOTION_LAMBDA = 'true';
		setCurrentRequestId(context.awsRequestId);
		stopLeakDetection();
		if (!context?.invokedFunctionArn) {
			throw new Error(
				'Lambda function unexpectedly does not have context.invokedFunctionArn',
			);
		}

		const expectedBucketOwner = context.invokedFunctionArn.split(':')[4];
		if (!expectedBucketOwner) {
			throw new Error('Expected current user ID');
		}

		await innerHandler({
			params,
			responseWriter,
			context: {
				requestId: context.awsRequestId,
				expectedBucketOwner,
				getRemainingTimeInMillis: () => context.getRemainingTimeInMillis(),
			},
			providerSpecifics: LambdaClientInternals.awsImplementation,
			insideFunctionSpecifics: serverAwsImplementation,
		});
	} catch (err) {
		if (!buffered) {
			throw err;
		}

View on GitHub (pinned to b2f4e34732)

Solutions

1. Ensure the stubbed/actual context.invokedFunctionArn is a full ARN of the form arn:aws:lambda:region:account-id:function:name.
2. Fix test fixtures to use a realistic 5+-part ARN including the numeric account ID.
3. If on a third-party Lambda-compatible platform, set the ARN correctly or run on real AWS Lambda where AWS guarantees the format.

Example fix

// before
invokedFunctionArn: 'arn:aws:lambda'
// after
invokedFunctionArn: 'arn:aws:lambda:eu-central-1:123456789012:function:remotion-render'

const parts = context.invokedFunctionArn.split(':');
if (parts.length < 5 || !parts[4]) {
  throw new Error('invokedFunctionArn must be a full ARN including account ID');
}

function hasAccountId(ctx: {invokedFunctionArn: string}): boolean {
  return Boolean(ctx.invokedFunctionArn.split(':')[4]);
}

try {
  await routine(params, context, responseWriter);
} catch (err) {
  if ((err as Error).message === 'Expected current user ID') {
    // malformed ARN; supply full arn:aws:lambda:region:account:function:name
  } else throw err;
}

When it happens

Trigger: context.invokedFunctionArn exists but is not a valid Lambda ARN (fewer than 5 colon-separated parts, or an empty account segment) — e.g. a fake/stubbed context in tests or a non-standard runtime.

Common situations: Local handler tests with simplified ARN strings, proxying invocations through a wrapper that truncates the ARN, or invoking on a non-AWS Lambda-compatible runtime that supplies an incomplete ARN.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

• Pass --s3-output-provider-endpoint when using S3 output prov
• Pass --force-bucket-name when using S3 output provider flags
• Pass --out-name when using S3 output provider flags.
• The 'siteName' argument must be a string if provided, but is
• The `siteName` must not be `.` or `..`. You passed: ${siteNa

AI-assisted analysis of remotion-dev/remotion@b2f4e34732 (2026-09-09). Data as JSON: /api/errors/5c1246f6864743c8. Report an issue: GitHub.