- Dependency Free
- Clean API
- Comprehensive Writers
IOWriter, io.Writer wrapperConsoleWriter, colorful & formattingFileWriter, rotating & effectiveAsyncWriter, asynchronously & performantMultiLevelWriter, multiple level dispatchSyslogWriter, memory efficient syslogJournalWriter, linux journal loggingEventlogWriter, windows eventlog logging
- Stdlib Interoperability
Logger.Std, transform to std log instancesLogger.Slog, transform to slog instancesSlogNewJSONHandler, drop-in replacement of slog.NewJSONHandler
- Utility Functions
Goid(), the goroutine id matches stack traceNewXID(), create a tracing idFastrandn(n uint32), fast pseudorandom uint32 in [0,n)IsTerminal(fd uintptr), isatty for golangPrintf(fmt string, a ...any), printf logging
- Extreme Performance
- Significantly faster than all other json loggers.
// Logger represents an active logging object that generates lines of JSON output to an io.Writer.
type Logger struct {
// Level defines log levels.
Level Level
// Caller determines if adds the file:line of the "caller" key.
// If Caller is negative, adds the full /path/to/file:line of the "caller" key.
Caller int
// TimeField defines the time field name in output. It uses "time" in if empty.
TimeField string
// TimeFormat specifies the time format in output. Uses RFC3339 with millisecond if empty.
// Strongly recommended to leave TimeFormat empty for optimal built-in log formatting performance.
// If set to `TimeFormatUnix/TimeFormatUnixMs`, timestamps will be formatted.
TimeFormat string
// TimeLocation specifices that the location of TimeFormat used. Uses time.Local if empty.
TimeLocation *time.Location
// Writer specifies the writer of output. It uses a wrapped os.Stderr Writer in if empty.
Writer log.Writer
}
// DefaultLogger is the global logger.
var DefaultLogger = Logger{
Level: DebugLevel,
Caller: 0,
TimeField: "",
TimeFormat: "",
Writer: &log.IOWriter{os.Stderr},
}// ConsoleWriter parses the JSON input and writes it in a colorized, human-friendly format to Writer.
// IMPORTANT: Don't use ConsoleWriter on critical path of a high concurrency and low latency application.
//
// Default output format:
// {Time} {Level} {Goid} {Caller} > {Message} {Key}={Value} {Key}={Value}
type ConsoleWriter struct {
// ColorOutput determines if used colorized output.
ColorOutput bool
// QuoteString determines if quoting string values.
QuoteString bool
// EndWithMessage determines if output message in the end of line.
EndWithMessage bool
// Writer is the output destination. using os.Stderr if empty.
Writer io.Writer
// Formatter specifies an optional text formatter for creating a customized output,
// If it is set, ColorOutput, QuoteString and EndWithMessage will be ignored.
Formatter func(w io.Writer, args *FormatterArgs) (n int, err error)
}
// FormatterArgs is a parsed sturct from json input
type FormatterArgs struct {
Time string // "2019-07-10T05:35:54.277Z"
Level string // "info"
Caller string // "prog.go:42"
CallerFunc string // "main.main"
Goid string // "123"
Stack string // "<stack string>"
Message string // "a structure message"
KeyValues []struct {
Key string // "foo"
Value string // "bar"
ValueType byte // 's'
}
}// FileWriter is an Writer that writes to the specified filename.
type FileWriter struct {
// Filename is the file to write logs to. Backup log files will be retained
// in the same directory.
Filename string
// FileMode represents the file's mode and permission bits. The default
// mode is 0644
FileMode os.FileMode
// MaxSize is the maximum size in bytes of the log file before it gets rotated.
MaxSize int64
// MaxBackups is the maximum number of old log files to retain. The default
// is to retain all old log files
MaxBackups int
// TimeFormat specifies the time format of filename, uses `2006-01-02T15-04-05` as default format.
// If set with `TimeFormatUnix`, `TimeFormatUnixMs`, times are formated as UNIX timestamp.
TimeFormat string
// LocalTime determines if the time used for formatting the timestamps in
// log files is the computer's local time. The default is to use UTC time.
LocalTime bool
// HostName determines if the hostname used for formatting in log files.
HostName bool
// ProcessID determines if the pid used for formatting in log files.
ProcessID bool
// EnsureFolder ensures the file directory creation before writing.
EnsureFolder bool
// Header specifies an optional header function of log file after rotation,
Header func(fileinfo os.FileInfo) []byte
// Cleaner specifies an optional cleanup function of log backups after rotation,
// if not set, the default behavior is to delete more than MaxBackups log files.
Cleaner func(filename string, maxBackups int, matches []os.FileInfo)
}Highlights:
- FileWriter uses a symlink to point to the current log file with a timestamp, instead of renaming for rotation. On Windows, this may require administrator privileges.
- FileWriter
.Rotate()method does not rotate logs based on broad TimeFormat values (e.g., daily or monthly) until the file reaches itsMaxSize. - FileWriter combined with
AsyncWritercan maximize performance and throughput on Linux, see AsyncWriter section.
An out of box example.
package main
import (
"github.com/phuslu/log"
)
func main() {
log.Info().Str("foo", "bar").Int("number", 42).Msg("hi, phuslog")
log.Info().Msgf("foo=%s number=%d error=%+v", "bar", 42, "an error")
}
// Output:
// {"time":"2020-03-22T09:58:41.828Z","level":"info","foo":"bar","number":42,"message":"hi, phuslog"}
// {"time":"2020-03-22T09:58:41.828Z","level":"info","message":"foo=bar number=42 error=an error"}Note: By default log writes to
os.Stderr
To customize logger filed name and format.
package main
import (
"github.com/phuslu/log"
)
func main() {
log.DefaultLogger = log.Logger{
Level: log.InfoLevel,
Caller: 1,
TimeField: "date",
TimeFormat: "2006-01-02",
Writer: &log.IOWriter{os.Stdout},
}
log.Info().Str("foo", "bar").Msgf("hello %s", "world")
logger := log.Logger{
Level: log.InfoLevel,
TimeField: "ts",
TimeFormat: log.TimeFormatUnixMs,
}
logger.Log().Str("foo", "bar").Msg("")
}
// Output:
// {"date":"2019-07-04","level":"info","caller":"prog.go:16","foo":"bar","message":"hello world"}
// {"ts":1257894000000,"foo":"bar"}To allow the use of ordinary functions as log writers, use WriterFunc.
logger := log.Logger{
Writer: log.WriterFunc(func(e *log.Entry) (int, error) {
if e.Level >= log.ErrorLevel {
return os.Stderr.Write(e.Value())
} else {
return os.Stdout.Write(e.Value())
}
}),
}
logger.Info().Msg("a stdout entry")
logger.Error().Msg("a stderr entry")To log a human-friendly, colorized output, use ConsoleWriter.
if log.IsTerminal(os.Stderr.Fd()) {
log.DefaultLogger = log.Logger{
TimeFormat: "15:04:05",
Caller: 1,
Writer: &log.ConsoleWriter{
ColorOutput: true,
QuoteString: true,
EndWithMessage: true,
},
}
}
log.Debug().Int("everything", 42).Str("foo", "bar").Msg("hello world")
log.Info().Int("everything", 42).Str("foo", "bar").Msg("hello world")
log.Warn().Int("everything", 42).Str("foo", "bar").Msg("hello world")
log.Error().Err(errors.New("an error")).Msg("hello world")
Note: pretty logging also works on windows console
To log with user-defined format(e.g. glog), using ConsoleWriter.Formatter.
package main
import (
"fmt"
"io"
"github.com/phuslu/log"
)
type Glog struct {
Logger log.Logger
}
func (l *Glog) Infof(fmt string, a ...any) { l.Logger.Info().Msgf(fmt, a...) }
func (l *Glog) Warnf(fmt string, a ...any) { l.Logger.Warn().Msgf(fmt, a...) }
func (l *Glog) Errorf(fmt string, a ...any) { l.Logger.Error().Msgf(fmt, a...) }
var glog = &Glog{log.Logger{
Level: log.InfoLevel,
Caller: 2,
TimeFormat: "0102 15:04:05.999999",
Writer: &log.ConsoleWriter{Formatter: func(w io.Writer, a *log.FormatterArgs) (int, error) {
return fmt.Fprintf(w, "%c%s %s %s] %s\n%s", a.Level[0]-32, a.Time, a.Goid, a.Caller, a.Message, a.Stack)
}},
}}
func main() {
glog.Infof("hello glog %s", "Info")
glog.Warnf("hello glog %s", "Warn")
glog.Errorf("hello glog %s", "Error")
}
// Output:
// I0725 09:59:57.503246 19 console_test.go:183] hello glog Info
// W0725 09:59:57.504247 19 console_test.go:184] hello glog Warn
// E0725 09:59:57.504247 19 console_test.go:185] hello glog ErrorTo log with logfmt format, also using ConsoleWriter.Formatter.
package main
import (
"io"
"os"
"github.com/phuslu/log"
)
func main() {
log.DefaultLogger = log.Logger{
Level: log.InfoLevel,
Caller: 1,
TimeField: "ts",
TimeFormat: log.TimeFormatUnixWithMs,
Writer: &log.ConsoleWriter{
Formatter: log.LogfmtFormatter{"ts"}.Formatter,
Writer: io.MultiWriter(os.Stdout, os.Stderr),
},
}
log.Info().Str("foo", "bar").Int("no", 42).Msgf("a logfmt %s", "info")
}
// Output:
// ts=1257894000.000 level=info goid=1 caller="prog.go:20" foo="bar" no=42 "a logfmt info"
// ts=1257894000.000 level=info goid=1 caller="prog.go:20" foo="bar" no=42 "a logfmt info"To log to a daily-rotating file, use FileWriter.
package main
import (
"os"
"path/filepath"
"time"
"github.com/phuslu/log"
"github.com/robfig/cron/v3"
)
func main() {
logger := log.Logger{
Level: log.ParseLevel("info"),
Writer: &log.FileWriter{
Filename: "logs/main.log",
FileMode: 0600,
MaxSize: 100 * 1024 * 1024,
MaxBackups: 7,
EnsureFolder: true,
LocalTime: true,
},
}
runner := cron.New(cron.WithLocation(time.Local))
runner.AddFunc("0 0 * * *", func() { logger.Writer.(*log.FileWriter).Rotate() })
go runner.Run()
for {
time.Sleep(time.Second)
logger.Info().Msg("hello world")
}
}To rotating log file hourly and keep in a total size, use FileWriter.Cleaner.
package main
import (
"os"
"path/filepath"
"time"
"github.com/phuslu/log"
"github.com/robfig/cron/v3"
)
func main() {
logger := log.Logger{
Level: log.ParseLevel("info"),
Writer: &log.FileWriter{
Filename: "main.log",
MaxSize: 500 * 1024 * 1024,
Cleaner: func(filename string, maxBackups int, matches []os.FileInfo) {
var dir = filepath.Dir(filename)
var total int64
for i := len(matches) - 1; i >= 0; i-- {
total += matches[i].Size()
if total > 5*1024*1024*1024 {
os.Remove(filepath.Join(dir, matches[i].Name()))
}
}
},
},
}
runner := cron.New(cron.WithLocation(time.UTC))
runner.AddFunc("0 * * * *", func() { logger.Writer.(*log.FileWriter).Rotate() })
go runner.Run()
for {
time.Sleep(time.Second)
logger.Info().Msg("hello world")
}
}To rotating log file hourly and compressing after rotation, use FileWriter.Cleaner.
package main
import (
"os"
"os/exec"
"path/filepath"
"time"
"github.com/phuslu/log"
"github.com/robfig/cron/v3"
)
func main() {
logger := log.Logger{
Level: log.ParseLevel("info"),
Writer: &log.FileWriter{
Filename: "main.log",
MaxSize: 500 * 1024 * 1024,
Cleaner: func(filename string, maxBackups int, matches []os.FileInfo) {
var dir = filepath.Dir(filename)
for i, fi := range matches {
filename := filepath.Join(dir, fi.Name())
switch {
case i > maxBackups:
os.Remove(filename)
case !strings.HasSuffix(filename, ".gz"):
go exec.Command("nice", "gzip", filename).Run()
}
}
},
},
}
runner := cron.New(cron.WithLocation(time.UTC))
runner.AddFunc("0 * * * *", func() { logger.Writer.(*log.FileWriter).Rotate() })
go runner.Run()
for {
time.Sleep(time.Second)
logger.Info().Msg("hello world")
}
}For maximum write performance with asynchronous file logging, use AsyncWriter.
logger := log.Logger{
Level: log.InfoLevel,
Writer: &log.AsyncWriter{
ChannelSize: 4096,
DiscardOnFull: false,
Writer: &log.FileWriter{
Filename: "main.log",
FileMode: 0600,
MaxSize: 50 * 1024 * 1024,
MaxBackups: 7,
LocalTime: false,
},
},
}
logger.Info().Int("number", 42).Str("foo", "bar").Msg("a async info log")
logger.Warn().Int("number", 42).Str("foo", "bar").Msg("a async warn log")
logger.Writer.(io.Closer).Close()Highlights:
- To flush data and shut down safely, explicitly call the .Close() method.
- The automatic
writevenabling can boost write performance by up to 10x under high load.
To logging only 5% logs, use below idiom.
if log.Fastrandn(100) < 5 {
log.Log().Msg("hello world")
}To log to different writers by different levels, use MultiLevelWriter.
log.DefaultLogger.Writer = &log.MultiLevelWriter{
InfoWriter: &log.FileWriter{Filename: "main.INFO", MaxSize: 100<<20},
WarnWriter: &log.FileWriter{Filename: "main.WARNING", MaxSize: 100<<20},
ErrorWriter: &log.FileWriter{Filename: "main.ERROR", MaxSize: 100<<20},
ConsoleWriter: &log.ConsoleWriter{ColorOutput: true},
ConsoleLevel: log.ErrorLevel,
}
log.Info().Int("number", 42).Str("foo", "bar").Msg("a info log")
log.Warn().Int("number", 42).Str("foo", "bar").Msg("a warn log")
log.Error().Int("number", 42).Str("foo", "bar").Msg("a error log")To log to different writers, use MultiEntryWriter.
log.DefaultLogger.Writer = &log.MultiEntryWriter{
&log.ConsoleWriter{ColorOutput: true},
&log.FileWriter{Filename: "main.log", MaxSize: 100<<20},
&log.EventlogWriter{Source: ".NET Runtime", ID: 1000},
}
log.Info().Int("number", 42).Str("foo", "bar").Msg("a info log")To log to multiple io writers like io.MultiWriter, use below idiom.
log.DefaultLogger.Writer = &log.MultiIOWriter{
os.Stdout,
&log.FileWriter{Filename: "main.log", MaxSize: 100<<20},
}
log.Info().Int("number", 42).Str("foo", "bar").Msg("a info log")To logging to different logger as you want, use below idiom.
package main
import (
"github.com/phuslu/log"
)
var logger = struct {
Console log.Logger
Access log.Logger
Data log.Logger
}{
Console: log.Logger{
TimeFormat: "15:04:05",
Caller: 1,
Writer: &log.ConsoleWriter{
ColorOutput: true,
EndWithMessage: true,
},
},
Access: log.Logger{
Level: log.InfoLevel,
Writer: &log.FileWriter{
Filename: "access.log",
MaxSize: 50 * 1024 * 1024,
MaxBackups: 7,
LocalTime: false,
},
},
Data: log.Logger{
Level: log.InfoLevel,
Writer: &log.FileWriter{
Filename: "data.log",
MaxSize: 50 * 1024 * 1024,
MaxBackups: 7,
LocalTime: false,
},
},
}
func main() {
logger.Console.Info().Msgf("hello world")
logger.Access.Log().Msgf("handle request")
logger.Data.Log().Msgf("some data")
}SyslogWriter is a memory-efficient, cross-platform, dependency-free syslog writer, outperforms all other structured logging libraries.
package main
import (
"net"
"time"
"github.com/phuslu/log"
)
func main() {
go func() {
ln, _ := net.Listen("tcp", "127.0.0.1:1601")
for {
conn, _ := ln.Accept()
go func(c net.Conn) {
b := make([]byte, 8192)
n, _ := conn.Read(b)
println(string(b[:n]))
}(conn)
}
}()
syslog := log.Logger{
Level: log.InfoLevel,
TimeField: "ts",
TimeFormat: log.TimeFormatUnixMs,
Writer: &log.SyslogWriter{
Network: "tcp", // "unixgram",
Address: "127.0.0.1:1601", // "/run/systemd/journal/syslog",
Tag: "",
Marker: "@cee:",
Dial: net.Dial,
},
}
syslog.Info().Str("foo", "bar").Int("an", 42).Msg("a syslog info")
syslog.Warn().Str("foo", "bar").Int("an", 42).Msg("a syslog warn")
time.Sleep(2)
}
// Output:
// <6>2022-07-24T18:48:15+08:00 127.0.0.1:59277 [11516]: @cee:{"ts":1658659695428,"level":"info","foo":"bar","an":42,"message":"a syslog info"}
// <4>2022-07-24T18:48:15+08:00 127.0.0.1:59277 [11516]: @cee:{"ts":1658659695429,"level":"warn","foo":"bar","an":42,"message":"a syslog warn"}To log to linux systemd journald, using JournalWriter.
log.DefaultLogger.Writer = &log.JournalWriter{
JournalSocket: "/run/systemd/journal/socket",
}
log.Info().Int("number", 42).Str("foo", "bar").Msg("hello world")To log to windows system event, using EventlogWriter.
log.DefaultLogger.Writer = &log.EventlogWriter{
Source: ".NET Runtime",
ID: 1000,
}
log.Info().Int("number", 42).Str("foo", "bar").Msg("hello world")Using wrapped loggers for stdlog.
package main
import (
stdlog "log"
"os"
"github.com/phuslu/log"
)
func main() {
var logger *stdlog.Logger = (&log.Logger{
Level: log.InfoLevel,
TimeField: "date",
TimeFormat: "2006-01-02",
Caller: 1,
Context: log.NewContext(nil).Str("logger", "mystdlog").Int("myid", 42).Value(),
Writer: &log.IOWriter{os.Stdout},
}).Std("", 0)
logger.Print("hello from stdlog Print")
logger.Println("hello from stdlog Println")
logger.Printf("hello from stdlog %s", "Printf")
}Using wrapped loggers for slog.
package main
import (
"log/slog"
"github.com/phuslu/log"
)
func main() {
var logger *slog.Logger = (&log.Logger{
Level: log.InfoLevel,
TimeField: "date",
TimeFormat: "2006-01-02",
Caller: 1,
}).Slog()
logger = logger.With("logger", "a_test_slog").With("everything", 42)
logger.Info("hello from slog Info")
logger.Warn("hello from slog Warn")
logger.Error("hello from slog Error")
}Using as a high performance version of slog.JSONHandler.
package main
import (
"log/slog"
"os"
phuslog "github.com/phuslu/log"
)
func main() {
slog.SetDefault(slog.New(phuslog.SlogNewJSONHandler(os.Stderr, &slog.HandlerOptions{AddSource: true})))
slog.Info("hello from phuslog", "a", 1, "b", 2)
}To log with user-defined struct effectively, implements MarshalObject.
package main
import (
"github.com/phuslu/log"
)
type User struct {
ID int
Name string
Pass string
}
func (u *User) MarshalObject(e *log.Entry) {
e.Int("id", u.ID).Str("name", u.Name).Str("password", "***")
}
func main() {
log.Info().Object("user", &User{1, "neo", "123456"}).Msg("")
log.Info().EmbedObject(&User{2, "john", "abc"}).Msg("")
}
// Output:
// {"time":"2020-07-12T05:03:43.949Z","level":"info","user":{"id":1,"name":"neo","password":"***"}}
// {"time":"2020-07-12T05:03:43.949Z","level":"info","id":2,"name":"john","password":"***"}To add preserved key:value pairs to each entry, use NewContext.
logger := log.Logger{
Level: log.InfoLevel,
Context: log.NewContext(nil).Str("ctx", "some_ctx").Value(),
}
logger.Debug().Int("no0", 0).Msg("zero")
logger.Info().Int("no1", 1).Msg("first")
logger.Info().Int("no2", 2).Msg("second")
// Output:
// {"time":"2020-07-12T05:03:43.949Z","level":"info","ctx":"some_ctx","no1":1,"message":"first"}
// {"time":"2020-07-12T05:03:43.949Z","level":"info","ctx":"some_ctx","no2":2,"message":"second"}You can make a copy of log and add contextual fields.
package main
import (
"github.com/phuslu/log"
)
func main() {
sublogger := log.DefaultLogger
sublogger.Level = log.InfoLevel
sublogger.Context = log.NewContext(nil).Str("ctx", "some_ctx").Value()
sublogger.Debug().Int("no0", 0).Msg("zero")
sublogger.Info().Int("no1", 1).Msg("first")
sublogger.Info().Int("no2", 2).Msg("second")
log.Debug().Int("no3", 3).Msg("no context")
}
// Output:
// {"time":"2021-06-14T06:36:42.904+02:00","level":"info","ctx":"some_ctx","no1":1,"message":"first"}
// {"time":"2021-06-14T06:36:42.905+02:00","level":"info","ctx":"some_ctx","no2":2,"message":"second"}
// {"time":"2021-06-14T06:36:42.906+02:00","level":"debug","no3":3,"message":"no context"}The most common benchmarks(disabled/simple/caller/printf/any) against slog/zap/zerolog
// go test -v -cpu=4 -run=none -bench=. -benchtime=10s -benchmem bench_test.go
package main
import (
"io"
"log"
"log/slog"
"testing"
"time"
phuslog "github.com/phuslu/log"
"github.com/rs/zerolog"
"go.uber.org/zap"
"go.uber.org/zap/zapcore"
)
const msg = "The quick brown fox jumps over the lazy dog"
var obj = struct {Rate string; Low int; High float32}{"15", 16, 123.2}
// use time.RFC3339Nano for every logger so the comparison is apples-to-apples
func init() {
zerolog.TimeFieldFormat = time.RFC3339Nano
}
func zapEncoder() zapcore.Encoder {
encoderConfig := zap.NewProductionEncoderConfig()
encoderConfig.EncodeTime = zapcore.RFC3339NanoTimeEncoder
return zapcore.NewJSONEncoder(encoderConfig)
}
func BenchmarkSlogDisabled(b *testing.B) {
logger := slog.New(slog.NewJSONHandler(io.Discard, nil))
for i := 0; i < b.N; i++ {
logger.Debug(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogSimple(b *testing.B) {
logger := slog.New(slog.NewJSONHandler(io.Discard, nil))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogPrintf(b *testing.B) {
slog.SetDefault(slog.New(slog.NewJSONHandler(io.Discard, nil)))
for i := 0; i < b.N; i++ {
log.Printf("rate=%s low=%d high=%f msg=%s", "15", 16, 123.2, msg)
}
}
func BenchmarkSlogCaller(b *testing.B) {
logger := slog.New(slog.NewJSONHandler(io.Discard, &slog.HandlerOptions{AddSource: true}))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogAny(b *testing.B) {
logger := slog.New(slog.NewJSONHandler(io.Discard, nil))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "object", &obj)
}
}
func BenchmarkSlogPhusDisabled(b *testing.B) {
logger := slog.New(phuslog.SlogNewJSONHandler(io.Discard, nil))
for i := 0; i < b.N; i++ {
logger.Debug(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogPhusSimple(b *testing.B) {
logger := slog.New(phuslog.SlogNewJSONHandler(io.Discard, nil))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogPhusPrintf(b *testing.B) {
slog.SetDefault(slog.New(phuslog.SlogNewJSONHandler(io.Discard, nil)))
for i := 0; i < b.N; i++ {
log.Printf("rate=%s low=%d high=%f msg=%s", "15", 16, 123.2, msg)
}
}
func BenchmarkSlogPhusCaller(b *testing.B) {
logger := slog.New(phuslog.SlogNewJSONHandler(io.Discard, &slog.HandlerOptions{AddSource: true}))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogPhusAny(b *testing.B) {
logger := slog.New(phuslog.SlogNewJSONHandler(io.Discard, nil))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "object", &obj)
}
}
func BenchmarkZapDisabled(b *testing.B) {
logger := zap.New(zapcore.NewCore(
zapEncoder(),
zapcore.AddSync(io.Discard),
zapcore.InfoLevel,
)).Sugar()
for i := 0; i < b.N; i++ {
logger.Debugw(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkZapSimple(b *testing.B) {
logger := zap.New(zapcore.NewCore(
zapEncoder(),
zapcore.AddSync(io.Discard),
zapcore.InfoLevel,
)).Sugar()
for i := 0; i < b.N; i++ {
logger.Infow(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkZapPrintf(b *testing.B) {
logger := zap.New(zapcore.NewCore(
zapEncoder(),
zapcore.AddSync(io.Discard),
zapcore.InfoLevel,
)).Sugar()
for i := 0; i < b.N; i++ {
logger.Infof("rate=%s low=%d high=%f msg=%s", "15", 16, 123.2, msg)
}
}
func BenchmarkZapCaller(b *testing.B) {
logger := zap.New(zapcore.NewCore(
zapEncoder(),
zapcore.AddSync(io.Discard),
zapcore.InfoLevel),
zap.AddCaller(),
).Sugar()
for i := 0; i < b.N; i++ {
logger.Infow(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkZapAny(b *testing.B) {
logger := zap.New(zapcore.NewCore(
zapEncoder(),
zapcore.AddSync(io.Discard),
zapcore.InfoLevel,
)).Sugar()
for i := 0; i < b.N; i++ {
logger.Infow(msg, "rate", "15", "low", 16, "object", &obj)
}
}
func BenchmarkZeroLogDisabled(b *testing.B) {
zerolog.SetGlobalLevel(zerolog.InfoLevel)
logger := zerolog.New(io.Discard).With().Timestamp().Logger()
for i := 0; i < b.N; i++ {
logger.Debug().Str("rate", "15").Int("low", 16).Float32("high", 123.2).Msg(msg)
}
}
func BenchmarkZeroLogSimple(b *testing.B) {
logger := zerolog.New(io.Discard).With().Timestamp().Logger()
for i := 0; i < b.N; i++ {
logger.Info().Str("rate", "15").Int("low", 16).Float32("high", 123.2).Msg(msg)
}
}
func BenchmarkZeroLogPrintf(b *testing.B) {
logger := zerolog.New(io.Discard).With().Timestamp().Logger()
for i := 0; i < b.N; i++ {
logger.Info().Msgf("rate=%s low=%d high=%f msg=%s", "15", 16, 123.2, msg)
}
}
func BenchmarkZeroLogCaller(b *testing.B) {
logger := zerolog.New(io.Discard).With().Caller().Timestamp().Logger()
for i := 0; i < b.N; i++ {
logger.Info().Str("rate", "15").Int("low", 16).Float32("high", 123.2).Msg(msg)
}
}
func BenchmarkZeroLogAny(b *testing.B) {
logger := zerolog.New(io.Discard).With().Timestamp().Logger()
for i := 0; i < b.N; i++ {
logger.Info().Any("rate", "15").Any("low", 16).Any("object", &obj).Msg(msg)
}
}
func BenchmarkPhusLogDisabled(b *testing.B) {
logger := phuslog.Logger{Level: phuslog.InfoLevel, TimeFormat: time.RFC3339Nano, Writer: phuslog.IOWriter{io.Discard}}
for i := 0; i < b.N; i++ {
logger.Debug().Str("rate", "15").Int("low", 16).Float32("high", 123.2).Msg(msg)
}
}
func BenchmarkPhusLogSimple(b *testing.B) {
logger := phuslog.Logger{TimeFormat: time.RFC3339Nano, Writer: phuslog.IOWriter{io.Discard}}
for i := 0; i < b.N; i++ {
logger.Info().Str("rate", "15").Int("low", 16).Float32("high", 123.2).Msg(msg)
}
}
func BenchmarkPhusLogPrintf(b *testing.B) {
logger := phuslog.Logger{TimeFormat: time.RFC3339Nano, Writer: phuslog.IOWriter{io.Discard}}
for i := 0; i < b.N; i++ {
logger.Info().Msgf("rate=%s low=%d high=%f msg=%s", "15", 16, 123.2, msg)
}
}
func BenchmarkPhusLogCaller(b *testing.B) {
logger := phuslog.Logger{Caller: 1, TimeFormat: time.RFC3339Nano, Writer: phuslog.IOWriter{io.Discard}}
for i := 0; i < b.N; i++ {
logger.Info().Str("rate", "15").Int("low", 16).Float32("high", 123.2).Msg(msg)
}
}
func BenchmarkPhusLogAny(b *testing.B) {
logger := phuslog.Logger{TimeFormat: time.RFC3339Nano, Writer: phuslog.IOWriter{io.Discard}}
for i := 0; i < b.N; i++ {
logger.Info().Any("rate", "15").Any("low", 16).Any("object", &obj).Msg(msg)
}
}A Performance result as below, for daily benchmark results see github actions
goos: linux
goarch: amd64
pkg: bench
cpu: AMD EPYC 7763 64-Core Processor
BenchmarkSlogDisabled-4 832596027 7.216 ns/op 0 B/op 0 allocs/op
BenchmarkSlogSimple-4 4683106 1274 ns/op 16 B/op 2 allocs/op
BenchmarkSlogPrintf-4 6664480 898.9 ns/op 80 B/op 1 allocs/op
BenchmarkSlogCaller-4 2747516 2155 ns/op 600 B/op 8 allocs/op
BenchmarkSlogAny-4 4102998 1460 ns/op 0 B/op 0 allocs/op
BenchmarkZapDisabled-4 1000000000 5.626 ns/op 0 B/op 0 allocs/op
BenchmarkZapSimple-4 7254583 823.7 ns/op 384 B/op 1 allocs/op
BenchmarkZapPrintf-4 8547562 703.6 ns/op 80 B/op 1 allocs/op
BenchmarkZapCaller-4 2655981 2249 ns/op 648 B/op 3 allocs/op
BenchmarkZapAny-4 4199594 1418 ns/op 624 B/op 3 allocs/op
BenchmarkZeroLogDisabled-4 601615922 9.980 ns/op 0 B/op 0 allocs/op
BenchmarkZeroLogSimple-4 17752900 337.6 ns/op 0 B/op 0 allocs/op
BenchmarkZeroLogPrintf-4 11104765 539.6 ns/op 80 B/op 1 allocs/op
BenchmarkZeroLogCaller-4 4339143 1375 ns/op 320 B/op 4 allocs/op
BenchmarkZeroLogAny-4 4008674 1501 ns/op 696 B/op 11 allocs/op
BenchmarkPhusLogDisabled-4 620260744 9.661 ns/op 0 B/op 0 allocs/op
BenchmarkPhusLogSimple-4 28010372 214.2 ns/op 0 B/op 0 allocs/op
BenchmarkPhusLogPrintf-4 17410651 343.0 ns/op 0 B/op 0 allocs/op
BenchmarkPhusLogCaller-4 11248803 546.1 ns/op 0 B/op 0 allocs/op
BenchmarkPhusLogAny-4 10583113 567.8 ns/op 0 B/op 0 allocs/op
PASS
ok bench 172.467s
As slog handlers, comparing with stdlib/zap/zerolog implementations
// go test -v -cpu=1 -run=none -bench=. -benchtime=10s -benchmem bench_test.go
package bench
import (
"io"
"log/slog"
"testing"
"time"
phuslog "github.com/phuslu/log"
"github.com/rs/zerolog"
seankhliao "go.seankhliao.com/svcrunner/v3/jsonlog"
"go.uber.org/zap"
"go.uber.org/zap/exp/zapslog"
"go.uber.org/zap/zapcore"
)
const msg = "The quick brown fox jumps over the lazy dog"
// use time.RFC3339Nano for every logger so the comparison is apples-to-apples
func init() {
zerolog.TimeFieldFormat = time.RFC3339Nano
}
func zapEncoder() zapcore.Encoder {
encoderConfig := zap.NewProductionEncoderConfig()
encoderConfig.EncodeTime = zapcore.RFC3339NanoTimeEncoder
return zapcore.NewJSONEncoder(encoderConfig)
}
func BenchmarkSlogSimpleStd(b *testing.B) {
logger := slog.New(slog.NewJSONHandler(io.Discard, nil))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogGroupsStd(b *testing.B) {
logger := slog.New(slog.NewJSONHandler(io.Discard, nil)).With("a", 1).WithGroup("g").With("b", 2)
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogSimpleZap(b *testing.B) {
logcore := zapcore.NewCore(
zapEncoder(),
zapcore.AddSync(io.Discard),
zapcore.InfoLevel,
)
logger := slog.New(zapslog.NewHandler(logcore))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogGroupsZap(b *testing.B) {
logcore := zapcore.NewCore(
zapEncoder(),
zapcore.AddSync(io.Discard),
zapcore.InfoLevel,
)
logger := slog.New(zapslog.NewHandler(logcore)).With("a", 1).WithGroup("g").With("b", 2)
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogSimpleZerolog(b *testing.B) {
logger := slog.New(zerolog.NewSlogHandler(zerolog.New(io.Discard).Level(zerolog.InfoLevel)))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogGroupsZerolog(b *testing.B) {
logger := slog.New(zerolog.NewSlogHandler(zerolog.New(io.Discard).Level(zerolog.InfoLevel))).With("a", 1).WithGroup("g").With("b", 2)
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogSimpleSeankhliao(b *testing.B) {
logger := slog.New(seankhliao.New(slog.LevelInfo, io.Discard))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogGroupsSeankhliao(b *testing.B) {
logger := slog.New(seankhliao.New(slog.LevelInfo, io.Discard)).With("a", 1).WithGroup("g").With("b", 2)
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogSimplePhuslog(b *testing.B) {
logger := slog.New((&phuslog.Logger{TimeFormat: time.RFC3339Nano, Writer: phuslog.IOWriter{io.Discard}}).Slog().Handler())
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogGroupsPhuslog(b *testing.B) {
logger := slog.New((&phuslog.Logger{TimeFormat: time.RFC3339Nano, Writer: phuslog.IOWriter{io.Discard}}).Slog().Handler()).With("a", 1).WithGroup("g").With("b", 2)
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogSimplePhuslogStd(b *testing.B) {
logger := slog.New(phuslog.SlogNewJSONHandler(io.Discard, nil))
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}
func BenchmarkSlogGroupsPhuslogStd(b *testing.B) {
logger := slog.New(phuslog.SlogNewJSONHandler(io.Discard, nil)).With("a", 1).WithGroup("g").With("b", 2)
for i := 0; i < b.N; i++ {
logger.Info(msg, "rate", "15", "low", 16, "high", 123.2)
}
}A Performance result as below, for daily benchmark results see github actions
goos: linux
goarch: amd64
pkg: bench
cpu: AMD EPYC 7763 64-Core Processor
BenchmarkSlogSimpleStd 4433433 1282 ns/op 16 B/op 2 allocs/op
BenchmarkSlogGroupsStd 4600296 1302 ns/op 16 B/op 2 allocs/op
BenchmarkSlogSimpleZap 4900659 1245 ns/op 192 B/op 1 allocs/op
BenchmarkSlogGroupsZap 4780567 1271 ns/op 192 B/op 1 allocs/op
BenchmarkSlogSimpleZerolog 7286929 833.8 ns/op 0 B/op 0 allocs/op
BenchmarkSlogGroupsZerolog 5979396 1003 ns/op 0 B/op 0 allocs/op
BenchmarkSlogSimplePhuslog 8707195 702.8 ns/op 0 B/op 0 allocs/op
BenchmarkSlogGroupsPhuslog 8724584 691.0 ns/op 0 B/op 0 allocs/op
BenchmarkSlogSimplePhuslogStd 10154598 590.5 ns/op 0 B/op 0 allocs/op
BenchmarkSlogGroupsPhuslogStd 10054032 604.5 ns/op 0 B/op 0 allocs/op
PASS
ok bench 83.775s
As a drop-in replacement for slog.JSONHandler, it provides 50% to 100% speedup and full compatibility.
// go test -v -args -useWarnings && go test -v -run=none -bench=. -args -useWarnings
// a special thanks to @madkins23 for the help, with reference to https://github.com/phuslu/log/pull/70
package bench
import (
"io"
"log/slog"
"testing"
benchtests "github.com/madkins23/go-slog/bench/tests"
"github.com/madkins23/go-slog/infra"
"github.com/madkins23/go-slog/infra/warning"
verifytests "github.com/madkins23/go-slog/verify/tests"
"github.com/phuslu/log"
"github.com/stretchr/testify/suite"
)
func BenchmarkSlogJSON(b *testing.B) {
slogNewJSONHandler := func(w io.Writer, options *slog.HandlerOptions) slog.Handler {
return slog.NewJSONHandler(w, options)
}
creator := infra.NewCreator("slog/JSONHandler", slogNewJSONHandler, nil,
`^slog/JSONHandler^ is the JSON handler provided with the ^slog^ library.
It is fast and as a part of the Go distribution it is used
along with published documentation as a model for ^slog.Handler^ behavior.`,
map[string]string{
"slog/JSONHandler": "https://pkg.go.dev/log/slog#JSONHandler",
})
slogSuite := benchtests.NewSlogBenchmarkSuite(creator)
benchtests.Run(b, slogSuite)
}
func BenchmarkPhusluSlog(b *testing.B) {
creator := infra.NewCreator("phuslu/slog", log.SlogNewJSONHandler, nil,
`^phuslu/slog^ is a wrapper around the pre-existing ^phuslu/log^ logging library.`,
map[string]string{
"phuslu/log": "https://github.com/phuslu/log",
})
slogSuite := benchtests.NewSlogBenchmarkSuite(creator)
benchtests.Run(b, slogSuite)
}
func TestVerifyPhusluSlog(t *testing.T) {
creator := infra.NewCreator("phuslu/slog", log.SlogNewJSONHandler, nil,
`^phuslu/slog^ is a wrapper around the pre-existing ^phuslu/log^ logging library.`,
map[string]string{
"phuslu/log": "https://github.com/phuslu/log",
})
slogSuite := verifytests.NewSlogTestSuite(creator)
slogSuite.WarnOnly(warning.Duplicates)
suite.Run(t, slogSuite)
}
func TestMain(m *testing.M) {
warning.WithWarnings(m)
}A Performance result as below, for daily go-slog results see github actions
goos: linux
goarch: amd64
cpu: AMD EPYC 7763 64-Core Processor
BenchmarkSlogJSON/BenchmarkAttributes-4 788606 1516 ns/op 275.80 MB/s 256 B/op 3 allocs/op
BenchmarkSlogJSON/BenchmarkBigGroup-4 35481 34303 ns/op 463.48 MB/s 48 B/op 1 allocs/op
BenchmarkSlogJSON/BenchmarkDisabled-4 262674124 3.992 ns/op 0 B/op 0 allocs/op
BenchmarkSlogJSON/BenchmarkKeyValues-4 814696 1676 ns/op 249.33 MB/s 256 B/op 3 allocs/op
BenchmarkSlogJSON/BenchmarkLogging-4 41451 26383 ns/op 333.36 MB/s 0 B/op 0 allocs/op
BenchmarkSlogJSON/BenchmarkSimple-4 4056388 351.5 ns/op 236.11 MB/s 0 B/op 0 allocs/op
BenchmarkSlogJSON/BenchmarkSimpleSource-4 1304044 926.1 ns/op 327.16 MB/s 584 B/op 6 allocs/op
BenchmarkSlogJSON/BenchmarkWithAttrsAttributes-4 865826 1542 ns/op 509.07 MB/s 256 B/op 3 allocs/op
BenchmarkSlogJSON/BenchmarkWithAttrsKeyValues-4 808782 1565 ns/op 501.71 MB/s 256 B/op 3 allocs/op
BenchmarkSlogJSON/BenchmarkWithAttrsSimple-4 3993020 303.2 ns/op 1484.30 MB/s 0 B/op 0 allocs/op
BenchmarkSlogJSON/BenchmarkWithGroupAttributes-4 860944 1541 ns/op 280.40 MB/s 256 B/op 3 allocs/op
BenchmarkSlogJSON/BenchmarkWithGroupKeyValues-4 740656 1604 ns/op 269.32 MB/s 256 B/op 3 allocs/op
BenchmarkPhusluSlog/BenchmarkAttributes-4 1224932 925.7 ns/op 467.73 MB/s 240 B/op 1 allocs/op
BenchmarkPhusluSlog/BenchmarkBigGroup-4 73568 16224 ns/op 979.99 MB/s 48 B/op 1 allocs/op
BenchmarkPhusluSlog/BenchmarkDisabled-4 363444417 3.287 ns/op 0 B/op 0 allocs/op
BenchmarkPhusluSlog/BenchmarkKeyValues-4 1000000 1007 ns/op 429.84 MB/s 240 B/op 1 allocs/op
BenchmarkPhusluSlog/BenchmarkLogging-4 90266 13506 ns/op 651.70 MB/s 0 B/op 0 allocs/op
BenchmarkPhusluSlog/BenchmarkSimple-4 8443231 143.7 ns/op 577.65 MB/s 0 B/op 0 allocs/op
BenchmarkPhusluSlog/BenchmarkSimpleSource-4 5979291 201.1 ns/op 1332.91 MB/s 0 B/op 0 allocs/op
BenchmarkPhusluSlog/BenchmarkWithAttrsAttributes-4 1276758 956.9 ns/op 851.70 MB/s 240 B/op 1 allocs/op
BenchmarkPhusluSlog/BenchmarkWithAttrsKeyValues-4 1000000 1004 ns/op 812.06 MB/s 240 B/op 1 allocs/op
BenchmarkPhusluSlog/BenchmarkWithAttrsSimple-4 8165066 148.9 ns/op 3123.47 MB/s 0 B/op 0 allocs/op
BenchmarkPhusluSlog/BenchmarkWithGroupAttributes-4 1283709 931.9 ns/op 479.66 MB/s 240 B/op 1 allocs/op
BenchmarkPhusluSlog/BenchmarkWithGroupKeyValues-4 1209993 971.6 ns/op 460.05 MB/s 240 B/op 1 allocs/op
PASS
ok bench 36.713s
In summary, phuslog offers a blend of low latency, minimal memory usage, and efficient logging across various scenarios, making it an excellent option for high-performance logging in Go applications.
This log is heavily inspired by zerolog, glog, gjson and lumberjack.