filtering liveness probe access logs

[glehmann]

we are using sws in kubernetes, with a liveness probe configured to check the status of the sws instance

          livenessProbe:
            httpGet:
              path: /
              port: http
            periodSeconds: 5

this works very well, but generates a lot of logs of very low value for us:

…
2023-07-06T09:29:08.148155Z  INFO static_web_server::handler: incoming request: method=GET uri=/
2023-07-06T09:29:13.148495Z  INFO static_web_server::handler: incoming request: method=GET uri=/
2023-07-06T09:29:18.148100Z  INFO static_web_server::handler: incoming request: method=GET uri=/
2023-07-06T09:29:23.147758Z  INFO static_web_server::handler: incoming request: method=GET uri=/
…

I've found a way to globally change the log level, but that would also disable the logs for the actual requests.

Is there a way to filter the logs in sws?

[joseluisq]

Unfortunately, there is no way from the settings right now to keep some access info level logs and disable others. E.g If you go with error level then warn, info and all the verbose ones will be not shown.

So probably we will need to introduce some way for fine-grained logs. Probably via some access log setting or so. See discussion.
If you have ideas feel free to let me know.

[joseluisq]

Another thing that I'm thinking of is a built-in GET /health endpoint to health check SWS but just a random idea.

[glehmann]

I like your idea of a builtin /health endpoint. Do you think that may not be to difficult to implement? If no I may give it a try :)

[joseluisq]

Then you could give our codebase a try.
I think you could start proposing this in an issue.

[joseluisq]

A question, is your liveness probe also caring about the logs shown, or is it just enough with receiving a 200 OK?

Additionally, if the liveness probe cares only about receiving a successful response then you could try to send a HEAD request instead.
See HTTP Methods Supported

[glehmann]

That would have been really nice, but unfortunately k8s does'nt support HEAD http probes yet. There are some discussions in kubernetes/enhancements#4012 but I have no idea if it will ever make it to the stable version.

[joseluisq]

This is resolved by #238