who wants to read a mess of words anyways
use github.com/rs/zerolog because I like the api and the output format
code gist
1» go test -bench . -benchmem
2goos: linux
3goarch: amd64
4pkg: t
5BenchmarkApexTxt-4 305184 3541 ns/op 1228 B/op 20 allocs/op
6BenchmarkApexJSON-4 275408 4287 ns/op 1568 B/op 23 allocs/op
7BenchmarkGokitTxt-4 1000000 1154 ns/op 468 B/op 5 allocs/op
8BenchmarkGokitJSON-4 319072 3619 ns/op 1232 B/op 22 allocs/op
9BenchmarkLog15JSON-4 172742 7028 ns/op 2208 B/op 33 allocs/op
10BenchmarkLog15Txt-4 324510 3578 ns/op 1376 B/op 20 allocs/op
11BenchmarkLogrusJSON-4 203190 5791 ns/op 1974 B/op 35 allocs/op
12BenchmarkLogrusTxt-4 260695 4694 ns/op 1056 B/op 23 allocs/op
13BenchmarkZapJSON-4 1000000 1057 ns/op 256 B/op 1 allocs/op
14BenchmarkZapTxt-4 724332 1560 ns/op 368 B/op 5 allocs/op
15BenchmarkZapSugarJSON-4 750585 1370 ns/op 512 B/op 1 allocs/op
16BenchmarkZapSugarTxt-4 605372 1855 ns/op 624 B/op 5 allocs/op
17BenchmarkZerologJSON-4 2005058 588 ns/op 0 B/op 0 allocs/op
18BenchmarkZerologTxt-4 98937 11678 ns/op 2873 B/op 93 allocs/op
19BenchmarkKlogInterface-4 736012 1631 ns/op 216 B/op 2 allocs/op
20BenchmarkKlogFormat-4 797425 1501 ns/op 216 B/op 2 allocs/op
21BenchmarkStdlibInterface-4 1978610 607 ns/op 48 B/op 1 allocs/op
22BenchmarkStdlibFormat-4 2119566 565 ns/op 48 B/op 1 allocs/op
23PASS
24ok t 23.216s
github.com/apex/loggithub.com/go-kit/kit/loggithub.com/inconshreveable/log15github.com/rs/zerologgithub.com/sirupsen/logrusgo.uber.org/zapnot structured:
k8s.io/klog (fork of glog)log (stdlib)code:
1import (
2 apex "github.com/apex/log"
3 "github.com/apex/log/handlers/json"
4 "github.com/apex/log/handlers/logfmt"
5)
6
7func Apex() {
8 fmt.Println("\nApex")
9 l := &apex.Logger{Handler: json.New(os.Stdout), Level: apex.InfoLevel}
10 l.WithFields(apex.Fields{"bool": true, "int": 1, "str": "s", "err": err}).Info("apex json")
11
12 l = &apex.Logger{Handler: logfmt.New(os.Stdout), Level: apex.InfoLevel}
13 l.WithFields(apex.Fields{"bool": true, "int": 1, "str": "s", "err": err}).Info("apex txt")
14}
output:
1Apex
2{"fields":{"bool":true,"err":{},"int":1,"str":"s"},"level":"info","timestamp":"2020-04-12T22:58:32.105258571+02:00","message":"apex json"}
3timestamp=2020-04-12T22:58:32.105372627+02:00 level=info message="apex txt" bool=true err="an err" int=1 str=s
code:
1import (
2 kitlog "github.com/go-kit/kit/log"
3)
4
5func Gokit() {
6 fmt.Println("\nGokit")
7 l := kitlog.NewJSONLogger(os.Stdout)
8 l.Log("gokit json", "bool", true, "int", 1, "str", "s", "err", err)
9
10 l = kitlog.NewLogfmtLogger(os.Stdout)
11 l.Log("gokit txt", "bool", true, "int", 1, "str", "s", "err", err)
12}
output:
1Gokit
2{"1":"str","an err":"(MISSING)","gokit json":"bool","s":"err","true":"int"}
3gokittxt=bool true=int 1=str s=err
code:
1import (
2 "github.com/inconshreveable/log15"
3)
4
5func Log15() {
6 fmt.Println("\nLog15")
7 l := log15.New()
8 l.SetHandler(log15.StreamHandler(os.Stdout, log15.JsonFormat()))
9 l.Info("log15 json", "bool", true, "int", 1, "str", "s", "err", err)
10
11 l = log15.New()
12 l.SetHandler(log15.StreamHandler(os.Stdout, log15.LogfmtFormat()))
13 l.Info("log15 json", "bool", true, "int", 1, "str", "s", "err", err)
14}
output:
1Log15
2{"bool":true,"err":"an err","int":1,"lvl":"info","msg":"log15 json","str":"s","t":"2020-04-12T22:58:32.105473094+02:00"}
3t=2020-04-12T22:58:32+0200 lvl=info msg="log15 json" bool=true int=1 str=s err="an err"
code:
1import (
2 "github.com/sirupsen/logrus"
3)
4
5func Logrus() {
6 fmt.Println("\nLogrus")
7 l := &logrus.Logger{Out: os.Stdout, Formatter: &logrus.JSONFormatter{}, Level: logrus.InfoLevel}
8 l.WithFields(logrus.Fields{"bool": true, "int": 1, "str": "s", "err": err}).Info("logrus json")
9
10 l = &logrus.Logger{Out: os.Stdout, Formatter: &logrus.TextFormatter{}, Level: logrus.InfoLevel}
11 l.WithFields(logrus.Fields{"bool": true, "int": 1, "str": "s", "err": err}).Info("logrus txt")
12}
output:
1Logrus
2{"bool":true,"err":"an err","int":1,"level":"info","msg":"logrus json","str":"s","time":"2020-04-12T22:58:32+02:00"}
3INFO[0000] logrus txt bool=true err="an err" int=1 str=s
code:
1import(
2 "go.uber.org/zap"
3)
4
5func Zap() {
6 fmt.Println("\nZap")
7 l, _ := zap.NewProduction()
8 l.Info("zap json", zap.Bool("bool", true), zap.Int("int", 1), zap.String("str", "s"), zap.Error(err))
9
10 l, _ = zap.NewDevelopment()
11 l.Info("zap txt", zap.Bool("bool", true), zap.Int("int", 1), zap.String("str", "s"), zap.Error(err))
12}
output:
1Zap
2{"level":"info","ts":1586725112.1056206,"caller":"testrepo-82/main.go:78","msg":"zap json","bool":true,"int":1,"str":"s","error":"an err"}
32020-04-12T22:58:32.105+0200 INFO testrepo-82/main.go:81 zap txt {"bool": true, "int": 1, "str": "s", "error": "an err"}
code:
1import(
2 "go.uber.org/zap"
3)
4
5func ZapSugar() {
6 fmt.Println("\nZap Sugar")
7 l, _ := zap.NewProduction()
8 l.Sugar().Infow("zap sugar json", "bool", true, "int", 1, "str", "s", "err", err)
9
10 l, _ = zap.NewDevelopment()
11 l.Sugar().Infow("zap sugar txt", "bool", true, "int", 1, "str", "s", "err", err)
12}
output:
1Zap Sugar
2{"level":"info","ts":1586725112.1056879,"caller":"testrepo-82/main.go:87","msg":"zap sugar json","bool":true,"int":1,"str":"s","err":"an err"}
32020-04-12T22:58:32.105+0200 INFO testrepo-82/main.go:90 zap sugar txt {"bool": true, "int": 1, "str": "s", "err": "an err"}
code:
1import(
2 "github.com/rs/zerolog"
3)
4
5func Zerolog() {
6 fmt.Println("\nZerolog")
7 l := zerolog.New(os.Stdout).With().Timestamp().Logger()
8 l.Info().Bool("bool", true).Int("int", 0).Str("str", "s").Err(err).Msg("zerolog json")
9
10 l = zerolog.New(zerolog.ConsoleWriter{Out: os.Stdout, NoColor: true, TimeFormat: time.RFC3339}).With().Timestamp().Logger()
11 l.Info().Bool("bool", true).Int("int", 1).Str("str", "s").Err(err).Msg("zerolog txt")
12}
output:
1Zerolog
2{"level":"info","bool":true,"int":0,"str":"s","error":"an err","time":"2020-04-12T22:58:32+02:00","message":"zerolog json"}
32020-04-12T22:58:32+02:00 INF zerolog txt error="an err" bool=true int=1 str=s
code:
1import(
2 "k8s.io/klog"
3)
4
5func Klog() {
6 fmt.Println("\nKlog")
7 klog.Info("klog", "bool", true, "int", 1, "str", "s", "err", err)
8 klog.Infof("klog bool=%v int=%v str=%v err=%v\n", true, 1, "s", err)
9}
1Klog
2I0412 22:58:32.105824 258002 main.go:104] klogbooltrueint1strserran err
3I0412 22:58:32.105840 258002 main.go:105] klog bool=true int=1 str=s err=an err
code:
1import(
2 "log"
3)
4
5func Std() {
6 fmt.Println("\nstdlib")
7 log.Println("stdlib", "bool", true, "int", 1, "str", "s", "err", err)
8 log.Printf("klog bool=%v int=%v str=%v err=%v\n", true, 1, "s", err)
9}
output:
1stdlib
22020/04/12 23:01:38 stdlib bool true int 1 str s err an err
32020/04/12 23:01:38 stdlib bool=true int=1 str=s err=an err