Golang logging package

go get github.com/leesper/holmes

Add one line at the top of your main function, and you can do somg logging by calling such as holmes.Debug(...)

• Support creating new log file every hour/minute(rolling);
• Can also print to stdout while writing to file;
• Support levels: debug, info, warn, error, fatal;
• Can change log file path by passing LogFilePath("./log") to holmes.Start()
• Generating log files named PROGRAM.YYYY-MM-DD-HH-MM.PID.log
• Support printing stacks of all go-routines when crashed

It is by default, a debug-level and print-to-stdout logger, you can pass parameters to change its behavior:

• DebugLevel - change logger to debug level
• InfoLevel - change logger to info level
• WarnLevel - change logger to warn level
• ErrorLevel - change logger to error level
• FatalLevel - change logger to fatal level
• LogFilePath - make logger write to disk file
• EveryHour - logging to different file every hour
• EveryMinute - logging to different file every minute
• AlsoStdout - also logging to stdout
• PrintStack - print stack infos of all go-routines when crashed

import "github.com/leesper/holmes"

func main() {
  // log files put in ./log, create new one every hour, also print to stdout
  defer holmes.Start(LogFilePath("./log"), EveryHour, AlsoStdout).Stop()
  holmes.Infof("%s", "If by life you were deceived,")
  holmes.Warnf("%s", "Don't be dismal, don't be wild!")
  holmes.Errorf("%s", "In the day of grief, be mild.")
  holmes.Infof("%s", "Merry days will come, believe.")
  ...
}

output:
2016/07/08 11:25:48  INFO [example.main] (example.go:48) - If by life you were deceived,
2016/07/08 11:25:48  WARN [example.main] (example.go:49) - Don't be dismal, don't be wild!
2016/07/08 11:25:48 ERROR [example.main] (example.go:50) - In the day of grief, be mild
2016/07/08 11:25:48  INFO [example.main] (example.go:51) - Merry days will come, believe.

BenchmarkFileLoggerSingleGoroutine-4  	  100000	     17694 ns/op
BenchmarkFileLoggerMultipleGoroutine-4	   50000	     37284 ns/op