Add Sentry integration
Sentry is the exception tracking tool we use everywhere else in GitLab.
The Go client library for Sentry integration is called 'Raven'. Getting Raven to send messages to the Sentry server is not that complicated but we would have to figure out what metadata to send along with errors, and what to hold back. (Leaking tokens and user data to an exception tracking service is a classic mistake.)
I think Sentry is worth having because although we can already count errors in Prometheus, we cannot observe exactly what errors are thrown. I prefer not to use Kibana for this. ;)
Edited by Andrew Newdigate