docs: troubleshooting guide for logging

[suztomo]

Document to explain how to change logging level for our libraries and underlying libraries.

Credit: I used @BenWhitehead 's snippet in bits benwhitehead/6166544285433856.

[rajatbhatta]

very minor nit: guilde -> guide in PR title

[blakeli0]

Can we add notes to indicate that this is only needed for REST APIs and io.groc.level below is only needed for gRPC APIs?

[suztomo]

Added comments.

Note that even when you use gRPC library, some authentication happens in HTTP 1.1.

[blakeli0]

Note that even when you use gRPC library, some authentication happens in HTTP 1.1.

Thanks, that's good to know. I guess it would be mostly covered by the com.google.auth.level=FINE below?

[suztomo]

That does not show HTTP headers.

[blakeli0]

I'm afraid this is only useful for handwritten libraries, for pure generated ones, we have very little logs, which is something we are planning to improve as part of the observability project. Can we add something to indicate it as well or maybe remove this section?

[suztomo]

Added that.

[blakeli0]

Thanks Tomo, this is very helpful! FYI, we are planning to improve the whole logging experience as part of the Observability project, so a lot of things could change, but this guide is pretty accurate as of now.

[lqiu96]

Looks good! IIRC, I have used this page previously for logging some of the HTTP requests for REGAPIC: http://googleapis.github.io/google-http-java-client/http-transport.html

I think your guide should cover the cases. Just FYI if you wanted to add anything else.

[suztomo]

@blakeli0 PTAL.

Observability project,

Looking forward.

[blakeli0]

Looks good! IIRC, I have used this page previously for logging some of the HTTP requests for REGAPIC: http://googleapis.github.io/google-http-java-client/http-transport.html

I think your guide should cover the cases. Just FYI if you wanted to add anything else.

Thanks for then note Lawrence! I think it should be already covered by com.google.api.level=ALL as com.google.api.client.http is a sub-package of com.google.api.