Holmes

Golang server logging package

Features

• 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

Things you can change

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

Benchmark

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

Installation

go get -u -v github.com/leesper/holmes

Usage

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

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.

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change. Please make sure to update tests as appropriate.