"undefined" messages reported from raven-js

[JimJty]

I just started using sentry. I am using hosted sentry with a local server copy of raven-js (3.7.0) and have been getting intermittent "undefined" errors from numerous users that I have been unable to reproduce. The stack trace points to raven-js:

Is this a bug, or is there additional troubleshooting steps I can do to narrow it down to my code.

Other errors log correctly. Its happening in different browsers/os's (recent examples: Windows 10 / Chrome 52, Windows XP / Chrome 38, Windows 7 / Firefox 48).

I am using the Angular 1 plugin, and copied the setup/install from sentry.io docs

<script src="lib/angular/angular.min.js"></script>
<script src="lib/raven-js/dist/raven.js"></script>
<script src="lib/raven-js/dist/plugins/angular.js"></script>
<script>
Raven
    .config('https://MYKEY@sentry.io/MYAPPID')
    .addPlugin(Raven.Plugins.Angular)
    .install();
</script>

[benvinegar]

It's not a bug. The highest frame is from a function that wraps async functions in try/catch. That try/catch statement (line 673) is catching an error, whose value is apparently undefined. Because it is not a real error object, there is no stack information, so Raven attempts to create a synthetic trace – which is how it gets any frame information at all.

You could get this stack trace from some piece of code (or library) that is doing this:

setTimeout(function () {
   // do stuff above
  throw error; // `error` is undefined
}, 500); // *some* async method, not necessarily setTimeout

[benvinegar]

These errors are frustrating, but ultimately we can only get what the browser and the code gives us – which isn't very much.

I'd look at breadcrumbs and other error metadata to see if there are other ways you can pin down what's happening. You could also audit your code for errant throw calls.

[JimJty]

Thanks, I'll do some more troubleshooting on my end.

[benvinegar]

@JimJty – get anywhere with this?

[benvinegar]

This was likely fixed in #872. Please re-open if you've upgraded to the latest Raven.js and still see this.