Frustrating 500 errors only on Vercel, useless logs

I build a new headless frontend with Svelte and locally (npm run dev or vercel dev) all is fine.

But sometimes I run into random 500 errors on Vercel while viewing pages. Even better, they are LPs and are exactly the same as all the other LPs that are working – but this one doesn’t.

The logs are not helpful. There is no error message and since that one page works fine on local, I cannot reproduce and debug the issue.

This happens so often it gets annoying as hell. This kind of ruins the whole headless experience for me and sometimes I wish I just used plain ol’ PHP … But the frontend is almost complete.

Is there someone else with similar issues? How I am supposed to debug such 500 errors that only happen on Vercel? I cannot just FTP into that and use console.log like PHP with var_dump. Hell, PHP even has log output with error messages and don’t need that approach. Why does Vercel logs don’t show error messages?!

I mean, look at that. What am I supposed to do with that log entry – frame it and hang on the wall? It is useless.

Hey @carstenjaksch !

I’m sorry you’re having a bad experience with our logs. If you see a 500 - it’s most likely that something in your function threw and you had a uncaught exception.

To debug this - you would need to filter for the request id - to see logs from the invocation that failed (you can click on it and press add filter)

Furthermore: We’re currently working on a refined logs experience that should make the entire story better by grouping all logs together from a single invocation. Can’t wait to show you what we’re working on!

3 Likes

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.