errorHandlerMiddleware

errorHandlerMiddleware(): MiddlewareObj<Record<string, unknown>, { body: string; headers: Record<string, string>; statusCode: number; }>

Defined in: packages/lambda-utils/src/middleware.ts:72

Catches any unhandled error from a handler or upstream middleware, maps it to the correct HTTP status code via statusCodeFor(), logs it with serializeError() (no stack traces leaked to response), and returns a structured JSON error response.

Usage — add LAST in the middleware chain so it catches everything:

export const handler = middy(serviceHandler) .use(injectLambdaContext(logger, { resetKeys: true })) .use(captureLambdaHandler(tracer)) .use(loggingMiddleware()) .use(errorHandlerMiddleware()); // ← always last

Returns

MiddlewareObj<Record<string, unknown>, { body: string; headers: Record<string, string>; statusCode: number; }>