I have noticed that stderr output from my apps shows in the monitoring view at ‘info’ level. Tested with nodejs console.error and process.stderr.write. The only error level logs I can see are from the Fly proxy.
I have a vector/loki/grafana setup in Fly and would like to alert and query based on log level, but since the correct level is not applied this is impossible without attaching additional information to the logs.
Is this something I’ve got wrong or is it a current platform limitation?
This is a platform limitation, like @pan guessed; everything is [info]. The only workaround is “attaching additional information”, along the lines that were alluded to up above.
JSON is one widely used way to accomplish that: people change their app to emit single-line JSON blobs and then configure their self-managed Vector instances to transform those into the correct log level, message, etc.
(People who are serious about logs generally do want their own Vector instance…)