go-logging

Advanced logger for Golang that supports multiple output formats and simple logging functions.

Simple Example

log.Info("Starting")
defer log.Info("Exiting")
a := 2
b := 3
sum := 5
log.Notice("sum of a and b", "a", a, "b", b, "sum", sum)
if err := doSomethingWithError(); err != nil {
	log.Error("could not do something with error", "error", err)
} else {
	log.Notice("successfully done something without error")
}

2020-04-17T08:59:51Z [INF] Starting
2020-04-17T08:59:51Z [NOT] sum of a and b A: 2 B: 3 SUM: 5
2020-04-17T08:59:51Z [ERR] could not do something with error ERROR: no such file or directory
2020-04-17T08:59:51Z [INF] Exiting

Advanced Example

opts := []log.Option{
	log.OptionEnableDebug(true),
	log.OptionWithTimeFormat(time.ANSIC),
	log.OptionEnableLocalTime(true),
	log.OptionWithLevelKey("_LVL"),
	log.OptionWithTimeKey("_TIME"),
	log.OptionWithMessageKey("message"),
	log.OptionWithStaticKV("_HOSTNAME", "my-hostname"),
	log.OptionWithStaticKV("_IP", "123.123.123.123"),
	log.OptionWithWriter(os.Stdout),
}
logger := log.New(log.FormatterJSON, opts...)
log.SetLogger(logger)
log.Info("Starting")
defer log.Info("Exiting")
a := 2
b := 3
log.Debug("calculating sum of a and b", "a", a, "b", b)
sum := a + b
log.Notice("sum of a and b", "a", a, "b", b, "sum", sum)
if err := doSomethingWithError(); err != nil {
	log.Error("could not do something with error", "error", err)
} else {
	log.Notice("successfully done something without error")
}

{"_HOSTNAME":"my-hostname","_IP":"123.123.123.123","_LVL":"Info","_TIME":"Fri Apr 17 11:40:52 2020","_message":"Starting"}
{"_HOSTNAME":"my-hostname","_IP":"123.123.123.123","_LVL":"Debug","_TIME":"Fri Apr 17 11:40:52 2020","_message":"calculating sum of a and b","a":2,"b":3}
{"_HOSTNAME":"my-hostname","_IP":"123.123.123.123","_LVL":"Notice","_TIME":"Fri Apr 17 11:40:52 2020","_message":"sum of a and b","a":2,"b":3,"sum":5}
{"_HOSTNAME":"my-hostname","_IP":"123.123.123.123","_LVL":"Error","_TIME":"Fri Apr 17 11:40:52 2020","_message":"could not do something with error","error":"no such file or directory"}
{"_HOSTNAME":"my-hostname","_IP":"123.123.123.123","_LVL":"Info","_TIME":"Fri Apr 17 11:40:52 2020","_message":"Exiting"}