node.jsamazon-web-servicesloggingamazon-cloudwatchpinojs

AWS Cloudwatch Node.js stack trace printed in separate log entries

Currently, when an error happens in my Node.js application, each line in the stack trace is printed in a separate log entry, as shown below:

enter image description here

What can I do so that, for a single error, its stack trace prints in a single log entry?

Solution

  • I figured out that we can customize the stack trace format using the V8 Stack Trace API: https://v8.dev/docs/stack-trace-api

    So, instead of being printed as \n separated, we can reformat it as a JSON string, so that Cloudwatch will parse it in a single log entry, like this:

    Error.prepareStackTrace = (err, stack) => JSON.stringify({
  message: err.message,
  stack: stack.map(frame => ({
    file: frame.getFileName(),
    function: frame.getFunctionName(),
    column: frame.getColumnNumber(),
    line: frame.getLineNumber()
  }))
});