Duplicate print in log

[shamanis]

go 1.9.2

logger := logging.MustGetLogger("main")
format := logging.MustStringFormatter(`%{time:2006-01-02 15:04:05.000} [%{level}] %{message}`)
backend := logging.NewLogBackend(os.Stdout, "", 0)
backendFormatter := logging.NewBackendFormatter(backend, format)
backendLevel := logging.AddModuleLevel(backend)
backendLevel.SetLevel(logging.DEBUG, "")
logging.SetBackend(backendLevel, backendFormatter)

logger.Debug("TestDebug")
logger.Warning("TestWarning")

2018-03-29 12:17:04.794 [DEBUG] TestDebug
TestWarning
2018-03-29 12:17:04.794 [WARNING] TestWarning

such behavior starting with the level WARNING Why?

[mashuiping]

@shamanis i thank the readme must have confused a lot of prgrammers:

1. Why the output is duplicate
2. How to set logging level

The answer to both questions is that the readme "example" has two backend! Just look into the logging.SetBeckend func

func SetBackend(backends ...Backend) LeveledBackend {
	var backend Backend
	if len(backends) == 1 {
		backend = backends[0]
	} else {
		backend = MultiLogger(backends...)
	}

	defaultBackend = AddModuleLevel(backend)
	return defaultBackend
}

So, just change your code as the following,

logger := logging.MustGetLogger("main")
format := logging.MustStringFormatter(`%{time:2006-01-02 15:04:05.000} [%{level}] %{message}`)
backend := logging.NewLogBackend(os.Stdout, "", 0)
backendFormatter := logging.NewBackendFormatter(backend, format)
logging.SetBackend(backendFormatter)
logging.SetLevel(logging.DEBUG, "main")
logger.Debug("TestDebug")
logger.Warning("TestWarning")

And if want to change log level, just

logging.SetLevel(logging.xxx, "main")

[RussoNC]

Yes I really think the readme should have a really simple example, and another where they show us an example with multiple backends, but other than that I love this lib!

[channprj]

It would be nice if more samples provided.