Override standard log library by using fluend-logger https://github.com/fluent/fluent-logger-golang
All log message print stdout and fluentd with tag goluent.<your hostname>.*.
This is inspired by http://12factor.net/
add this
<match goluent.**>
@type stdout
@id stdout_output
</match>
in your *.go file
import (
log "github.com/drobune/goluent"
)
log.Info("goluent now")
// 2015/07/03 15:33:10 goluent now
log.Errorf("over %v sec", 10)
//2015/07/03 15:37:00 over 10 sec