reset logger level when config isnt present

[puranamp]

Issue: Suppose we had a registered logger named a.b.c that we configured to have the level WARN. Then, we removed this configuration option and reconfigured. The a.b.c logger will still be set to WARN despite not specifying this.

Solution: Any loggers that no longer have a configuration are reset back to INFO. Also, logger changes are applied only once, so there is no undefined behavior of logs during reconfiguration.

[benjirewis]

Brought up a discussion offline, but I'm curious if we still want to go down this path of "process all log changes in config/reader.go instead of local_robot.go". Let's talk there before continuing.

[maximpertsov]

⚠️ disclaimer, this comment only applies if we stick with "processing all log changes in config/reader.go".

let's do the INFO reset after processing changes. i think the current approach has a small race condition where an existing logger configured with a non-INFO level is briefly reset to INFO

[benjirewis]

after processing changes

Sorry which "processing changes" are you referring to? If we put this block at the end of the function, wouldn't everything get set to INFO?

[maximpertsov]

sorry, i meant just the loggers that are still in the registry but not in the config configured by the config

[maximpertsov]

more specifically, we should keep a count of how many times each registered pattern is configured by a new config pattern, and then reset all registered loggers with 0 configurations back to INFO.

[benjirewis]

Ah cool; thanks for the clarification.

[maximpertsov]

discussed IRL, we should add a test that demonstrates this flow for a config that has resource log level configs.

[maximpertsov]

just noting that a logger can be created after we call loggerNamed but before we grab the write lock to create one ourselves - not sure how big of an issue that is.

[maximpertsov]

Suggested change

	logger, ok := globalLoggerRegistry.loggerNamed(name)
	globalLoggerRegistry.mu.Lock()
	defer globalLoggerRegistry.mu.Unlock()
	if !ok {
	globalLoggerRegistry.mu.Lock()
	defer globalLoggerRegistry.mu.Unlock()
	logger, ok := globalLoggerRegistry.loggers[name]
	if !ok {

[puranamp]

done

[benjirewis]

LGTM! Thanks.