⛱️ PSI Error-Handling

[exterkamp]

Summary

PSI Errors are not helpful to the users 😭, so let's make em' more useful!

Issues Where Errors are Just Straight Up Not Having A Good Time

• Lightrider RPC deadline instead of LHR+timeout #6802
• PSI: Issues with WebGL & other GPU tasks #8557
• RPC::SERVER_ERROR from PSI #9136
• Lack of transparency about Page Speed Insights errors #8195 (de-duped for this issue)
• Consistent style for lh-warnings #7011 lh-warning styling in report kind of bleeds in

PSI g/ threads:

• no_fcp
  • more, more, more
• err_doc
  • more
• fal_doc
• backend_err 😢
  • more, more, more, more, more, more, more, When I check my site(https://www.mangalkeshav.com) for page speed in the tool - Pagespeed insights - I get Backend error. #9146
• APP::5: Rendering Canceled - timeout

Errors within audits that are confusing:

• net::ERR_ACCESS_DENIED/net::ERR_FAILED
  • Failed to load resource: net::ERR_ACCESS_DENIED #9038
  • Font considered not accessible, but it is #9033
  • Browser errors were logged to the console #9276

Other Opportunities

• PSI doesn't support HTTP/2 (H2) #7326 <- highlights need of FAQ for known issues
  • [Pagespeed API] Support custom user agent in pagespeed API #7725 another good FAQ issue
• as a developer, I'd like to catch lighthouse errors in audits, gatherers, runtime etc outside of lighthouse #8812 Interesting error catching
• CrUX FAQ

What Do Errors Look Like?

• Runtime Errors != []
  

• 1 Form Factor errored, but the other didn't
  

• Infamous Backend Error
  

Recommendations

In Progress

• Better Docs on using PSI in general to avoid common pitfalls
• PSI FAQ for v5+ known errors + a reminder to check FAQ before making an issue

[connorjclark]

I can audit https://www.tensorflow.org/ directly with LR via the demo app. It takes 80+ seconds.

PSI has a 60 second timeout, so of course it doesn't make the cut. But the error I get is just Backend Error.

grr

[connorjclark]

PSI doubles codes in error messages. ex: (NO_FCP) (NO_FCP)

[jazyan]

@connorjclark and I found that the above comment is not reproducible 🙂

[connorjclark]

We're happy with how we present errors in PSI today. and this is old ui.