Setting different log levels per services does not work

[rhafer]

Describe the bug

Increasing the loglevel per service is currently not possible. E.g. starting ocis with:

OCIS_LOG_LEVEL=error PROXY_LOG_LEVEL=debug ocis/bin/ocis server

does not have the desired effect (debug log for proxy, error for all other services).

Something seems racy here. Sometimes the proxy (an a few other services!) will pick up the "debug" level. And sometime this setting just has no effect.

I guess this is at least partially related to the fact that we call zerolog.SetGlobalLevel() for every service during startup see:

ocis/ocis-pkg/log/log.go

Line 38 in 25ca415

switch strings.ToLower(options.Level) {