grpclog: grpc internal logging should respect log verbosity

[gyuho]

What version of gRPC are you using?

v1.7.4

What version of Go are you using (go version)?

Go 1.9.2

Problem

Balancer wrapper info logging does not respect verbosity

grpc-go/balancer_v1_wrapper.go

Lines 124 to 126 in 2720857

	for addrs := range notifyCh {
	grpclog.Infof("balancerWrapper: got update addr from Notify: %v\n", addrs)
	if bw.pickfirst {

where you can set with

SetLogger(grpclog.NewLoggerV2WithVerbosity(os.Stderr, os.Stderr, os.Stderr, 4))

Only transport package respects verbosity, while others don't.

grpc-go/transport/log.go

Lines 28 to 32 in 2720857

	func infof(format string, args ...interface{}) {
	if grpclog.V(logLevel) {
	grpclog.Infof(format, args...)
	}
	}

Could we add verbosity check to all internal logging?

ref. etcd-io/etcd#8994

[menghanl]

The log you are referring to is a Info log. Does it work for you to ignore all the Info logs?

Or if you are only interested in Errors,
grpclog.NewLoggerV2WithVerbosity(ioutil.Discard, ioutil.Discard, os.Stderr, 0) would work.

[gyuho]

@menghanl We want to see Warning/Error/Fatal, but opt out on Info (only when our --debug flag is off). So grpclog.NewLoggerV2WithVerbosity(ioutil.Discard, os.Stderr, os.Stderr, 0) would totally work.

Feel free to close this.

Thanks!