How to use WriteTo method of log Package

Best K6 code snippet using log.WriteTo

logger.go

Source:logger.go

1package logger2import (3	"fmt"4	"io"5	"os"6	"sync"7	"time"8)9// Level is the importance of a logged event10type Level uint811// log message importance12const (13	Debug   Level = iota // passed through without prepending timestamp14	Fatal                // irrecoverable error15	Error                // non-fatal but permanent degradation16	Warning              // temporary degradation or transient IO error or client error17	Info                 // unimportant but noteworthy18	Ignore               // don't print19)20// fatalExitCode is the code Logger will abort the process with if a fatal-level message is printed21const fatalExitCode int = 322// Logger is an utility for thread-safe and periodic logging.23// Use .Log() or one of its wrappers for issues that can be caught as they happen,24// PeriodicLogger for statistics and.25// Use .Compose() to make sure multi-statement messages get written as one.26// Should not be dereferenced or moved as it contains mutexes27type Logger struct {28	writeTo   io.WriteCloser29	writeLock sync.Mutex30	Treshold  Level31	p         periodic32}33// NewLogger creates a new logger with a minimum importance level and the interval to check the periodic loggers34// Even though Logger implements WriteCloser, Loggers should not be nested.35func NewLogger(writeTo io.WriteCloser, treshold Level) *Logger {36	l := &Logger{37		p:         newPeriodic(),38		writeLock: sync.Mutex{},39		writeTo:   writeTo,40		Treshold:  treshold,41	}42	go periodicRunner(l)43	return l44}45// Close the underlying Writer46func (l *Logger) Close() {47	l.writeLock.Lock()48	l.p.Close()49	// Might return an error, but where should the error message be written?50	_ = l.writeTo.Close()51	l.writeTo = nil52	// Dereferencing a nil is better than silently waiting forever on a lock.53	l.writeLock.Unlock()54}55func (l *Logger) prefixMessage(level Level) {56	if l.Treshold < Debug {57		fmt.Fprint(l.writeTo, time.Now().Format("2006-01-02 15:04:05: "))58	}59	if level == Warning {60		fmt.Fprint(l.writeTo, "WARNING: ")61	} else if level == Error {62		fmt.Fprint(l.writeTo, "ERROR: ")63	} else if level == Fatal && l.Treshold != Debug {64		fmt.Fprint(l.writeTo, "FATAL: ")65	}66}67// Compose allows holding the lock between multiple print68func (l *Logger) Compose(level Level) Composer {69	if level > l.Treshold {70		return Composer{71			writeTo:  nil,72			heldLock: nil,73			fatal:    false,74		}75	}76	l.writeLock.Lock()77	l.prefixMessage(level)78	return Composer{79		writeTo:  l.writeTo,80		heldLock: &l.writeLock,81		fatal:    level == Fatal,82	}83}84// Log writes the message if it passes the loggers importance treshold85func (l *Logger) Log(level Level, format string, args ...interface{}) {86	if level <= l.Treshold {87		l.writeLock.Lock()88		defer l.writeLock.Unlock()89		l.prefixMessage(level)90		if len(args) == 0 {91			fmt.Fprintln(l.writeTo, format)92		} else {93			fmt.Fprintf(l.writeTo, format, args...)94			fmt.Fprintln(l.writeTo)95		}96		if level == Fatal {97			os.Exit(fatalExitCode)98		}99	}100}101// WriteAdapter returns a Writer that writes through this logger with the given level.102// Writes that don't end in a newline are buffered to not split messages, but103// Composer-written messages might get split.104// The adapter is not synchronized because both the standard log.Logger and other instances105// of this type serializes writes, and the underlying Logger is synchronized.106func (l *Logger) WriteAdapter(level Level) io.Writer {107	if level > l.Treshold {108		return nil // faster and uses less memory109	}110	return &writeAdapter{111		logger: l,112		level:  level,113	}114}115// Wrappers around Log()116// Debug prints possibly interesting information, and is never filtered.117// Calls to this should probably not be committed.118func (l *Logger) Debug(format string, args ...interface{}) {119	l.Log(Debug, format, args...)120}121// Info prints unimportant but noteworthy events or information122func (l *Logger) Info(format string, args ...interface{}) {123	l.Log(Info, format, args...)124}125// Warning prints an error that might be recovered from126func (l *Logger) Warning(format string, args ...interface{}) {127	l.Log(Warning, format, args...)128}129// Error prints a non-fatal but permanent error130func (l *Logger) Error(format string, args ...interface{}) {131	l.Log(Error, format, args...)132}133// Fatal prints an error message and exits the program134func (l *Logger) Fatal(format string, args ...interface{}) {135	l.Log(Fatal, format, args...)136}137// FatalIf does nothing if cond is false, but otherwise prints the message and aborts the process.138func (l *Logger) FatalIf(cond bool, format string, args ...interface{}) {139	if cond {140		l.Fatal(format, args...)141	}142}143// FatalIfErr does nothing if err is nil, but otherwise prints "Failed to <..>: $err.Error()" and aborts the process.144func (l *Logger) FatalIfErr(err error, format string, args ...interface{}) {145	if err != nil {146		args = append(args, err.Error())147		l.Fatal("Failed to "+format+": %s", args...)148	}149}150// Composer lets you split a long message into multiple write statements151// End the message by calling Finish() or Close()152type Composer struct {153	fatal    bool154	writeTo  io.Writer // nil if level is ignored155	heldLock *sync.Mutex156}157// Write writes formatted text without a newline158func (c *Composer) Write(format string, args ...interface{}) {159	if c.writeTo != nil {160		if len(args) == 0 {161			fmt.Fprint(c.writeTo, format)162		} else {163			fmt.Fprintf(c.writeTo, format, args...)164		}165	}166}167// Writeln writes a formatted string plus a newline.168// This is identical to what Logger.Log() does.169func (c *Composer) Writeln(format string, args ...interface{}) {170	if c.writeTo != nil {171		if len(args) == 0 {172			fmt.Fprintln(c.writeTo, format)173		} else {174			fmt.Fprintf(c.writeTo, format, args...)175			fmt.Fprintln(c.writeTo)176		}177	}178}179// Finish writes a formatted line and then closes the composer.180func (c *Composer) Finish(format string, args ...interface{}) {181	c.Writeln(format, args...)182	c.Close()183}184// Close releases the mutex on the logger and exits the process for `Fatal` errors.185func (c *Composer) Close() {186	if c.writeTo != nil {187		c.heldLock.Unlock()188		c.writeTo = nil189		if c.fatal {190			os.Exit(fatalExitCode)191		}192	}193}194// See documentation on WriteAdapter195type writeAdapter struct {196	logger *Logger197	buf    []byte198	level  Level199}200// Always returns len(message), nil201func (wa *writeAdapter) Write(message []byte) (int, error) {202	if len(message) > 0 {203		wa.buf = append(wa.buf, message...)204		if wa.buf[len(wa.buf)-1] == byte('\n') { // flush it205			noTrailingNewline := wa.buf[:len(wa.buf)-1] // Log appends a newline206			wa.logger.Log(wa.level, "%s", string(noTrailingNewline))207			wa.buf = []byte{} // restart208		}209	}210	return len(message), nil211}...

loginfo_model.go

Source:loginfo_model.go

1package log2import (3	"bytes"4	"fmt"5	"io"6	"os"7	"runtime"8	"strconv"9)10const delim = ": "11// helpers for constructor12const (13	// NONE no logging14	NONE = 015	// INFO level16	INFO = 117	// WARN level18	WARN = 219	// DEBUG level20	DEBUG = 321)22var logLevels = []string{"NONE", "INFO", "WARN", "DEBUG"}23type Logger struct {24	logLevel int25	writeTo  io.Writer26	// for shorter form in case do not need caller file.27	withCaller bool28}29// New Constructor with levels 0 - no logging, 1 - info, 2 - warn, 3 - debug.30func NewLogger(level int, writeTo io.Writer, withCaller bool) *Logger {31	lev := convertLevel(level)32	if writeTo == nil {33		writeTo = os.Stdout34	}35	res := Logger{36		logLevel:   lev,37		writeTo:    writeTo,38		withCaller: withCaller,39	}40	res.Printf("Created logger, level %v.", logLevels[lev])41	return &res42}43func (i *Logger) Print(args ...interface{}) {44	buf := bufPool.Get().(*bytes.Buffer)45	buf.Reset()46	buf.WriteString(timestamp() + " " + fmt.Sprint(args...) + "\n")47	i.writeTo.Write(buf.Bytes())48	bufPool.Put(buf)49}50func (i *Logger) Printf(format string, args ...interface{}) {51	buf := bufPool.Get().(*bytes.Buffer)52	buf.Reset()53	buf.WriteString(timestamp() + " " + fmt.Sprintf(format, args...) + "\n")54	i.writeTo.Write(buf.Bytes())55	bufPool.Put(buf)56}57func (i *Logger) Info(args ...interface{}) {58	if i.logLevel == 0 {59		return60	}61	buf := bufPool.Get().(*bytes.Buffer)62	defer bufPool.Put(buf)63	buf.Reset()64	if i.withCaller {65		_, file, line, _ := runtime.Caller(1)66		buf.WriteString(timestamp() + " " + file + " Line" + delim + strconv.FormatInt(int64(line), 10) + " " + logLevels[1] + delim + fmt.Sprint(args...) + "\n")67		i.writeTo.Write(buf.Bytes())68		return69	}70	buf.WriteString(timestamp() + " " + logLevels[1] + delim + fmt.Sprint(args...) + "\n")71	i.writeTo.Write(buf.Bytes())72}73func (i *Logger) Infof(format string, args ...interface{}) {74	if i.logLevel == 0 {75		return76	}77	buf := bufPool.Get().(*bytes.Buffer)78	defer bufPool.Put(buf)79	buf.Reset()80	if i.withCaller {81		_, file, line, _ := runtime.Caller(1)82		buf.WriteString(timestamp() + " " + file + " Line" + delim + strconv.FormatInt(int64(line), 10) + " " + logLevels[1] + delim + fmt.Sprintf(format, args...) + "\n")83		i.writeTo.Write(buf.Bytes())84		return85	}86	buf.WriteString(timestamp() + " " + logLevels[1] + delim + fmt.Sprintf(format, args...) + "\n")87	i.writeTo.Write(buf.Bytes())88}89func (i *Logger) Warn(args ...interface{}) {90	if i.logLevel < 2 {91		return92	}93	buf := bufPool.Get().(*bytes.Buffer)94	defer bufPool.Put(buf)95	buf.Reset()96	if i.withCaller {97		_, file, line, _ := runtime.Caller(1)98		buf.WriteString(timestamp() + " " + file + " Line" + delim + strconv.FormatInt(int64(line), 10) + " " + colorWarn()(logLevels[2]) + delim + fmt.Sprint(args...) + "\n")99		i.writeTo.Write(buf.Bytes())100		return101	}102	buf.WriteString(timestamp() + " " + colorWarn()(logLevels[2]) + delim + fmt.Sprint(args...) + "\n")103	i.writeTo.Write(buf.Bytes())104}105func (i *Logger) Warnf(format string, args ...interface{}) {106	if i.logLevel < 2 {107		return108	}109	buf := bufPool.Get().(*bytes.Buffer)110	defer bufPool.Put(buf)111	buf.Reset()112	if i.withCaller {113		_, file, line, _ := runtime.Caller(1)114		buf.WriteString(timestamp() + " " + file + " Line" + delim + strconv.FormatInt(int64(line), 10) + " " + colorWarn()(logLevels[2]) + delim + fmt.Sprintf(format, args...) + "\n")115		i.writeTo.Write(buf.Bytes())116		return117	}118	buf.WriteString(timestamp() + " " + colorWarn()(logLevels[2]) + delim + fmt.Sprintf(format, args...) + "\n")119	i.writeTo.Write(buf.Bytes())120}121func (i *Logger) Debug(args ...interface{}) {122	if i.logLevel < 3 {123		return124	}125	buf := bufPool.Get().(*bytes.Buffer)126	defer bufPool.Put(buf)127	buf.Reset()128	if i.withCaller {129		_, file, line, _ := runtime.Caller(1)130		buf.WriteString(timestamp() + " " + file + " Line" + delim + strconv.FormatInt(int64(line), 10) + " " + colorDebug()(logLevels[3]) + delim + fmt.Sprint(args...) + "\n")131		i.writeTo.Write(buf.Bytes())132		return133	}134	buf.WriteString(timestamp() + " " + colorDebug()(logLevels[3]) + delim + fmt.Sprint(args...) + "\n")135	i.writeTo.Write(buf.Bytes())136}137func (i *Logger) Debugf(format string, args ...interface{}) {138	if i.logLevel < 3 {139		return140	}141	buf := bufPool.Get().(*bytes.Buffer)142	defer bufPool.Put(buf)143	buf.Reset()144	if i.withCaller {145		_, file, line, _ := runtime.Caller(1)146		buf.WriteString(timestamp() + " " + file + " Line" + delim + strconv.FormatInt(int64(line), 10) + " " + colorDebug()(logLevels[3]) + delim + fmt.Sprintf(format, args...) + "\n")147		i.writeTo.Write(buf.Bytes())148		return149	}150	buf.WriteString(timestamp() + " " + colorDebug()(logLevels[3]) + delim + fmt.Sprintf(format, args...) + "\n")151	i.writeTo.Write(buf.Bytes())152}153func (i *Logger) Fatal(args ...interface{}) {154	i.Print(args...)155	os.Exit(1)156}157func (i *Logger) GetLogLevel() int {158	return i.logLevel159}160func (i *Logger) SetLogLevel(level int) {161	i.logLevel = level162}...

model.go

Source:model.go

1package logs2import (3	"bufio"4	"fmt"5	"os"6)7/*8æ¥å¿æ¥å£9*/10type Logs interface {11	DeBug(logMsg error)12	Trace(logMsg error)13	Info(logMsg error)14	Warring(logmsg error)15	Error(logMsg error)16	Fatal(logMsg error)	17}18/*19æ¥å¿æä»¶20*/21type FileLog struct {22	Logpath string `json:logpath`23}24/*25ç»ç«¯æ¥å¿26*/27type ConsoleLog struct {28}29/*30å®ä¹ç»ç«¯æ¥å¿åæä»¶æ¥å¿çå¸¸é31*/32const (33	CONSOLE = iota34	FILE35)36/*37è¿åä¸ä¸ªæ¥å£38*/39func NewLogger(style int, path string) Logs {40	switch style {41	case CONSOLE:42		var logs Logs43		consolelog := newConsoleLog()44		logs = consolelog45		return logs46	case FILE:47		var logs Logs48		if path == "" {49			path = "/var/log/TennetlDB.log"50		}51		fileLog := newFileLog(path)52		logs = fileLog53		return logs54	default:55		return nil56	}57}58/*59åå»ºä¸ä¸ªæä»¶æ¥å¿60*/61func newFileLog(path string) *FileLog {62	return &FileLog{63		Logpath: path,64	}65}66/*67åå»ºä¸ä¸ªç»ç«¯æ¥å¿68*/69func newConsoleLog() *ConsoleLog {70	return &ConsoleLog{}71}72func (flog *FileLog)writeTo(level int,logMsg error){73	timeStr := logtime()74	file, err := os.OpenFile(flog.Logpath, os.O_CREATE|os.O_APPEND|os.O_RDWR, 0666)75	if err != nil {76		return77	}78	writer := bufio.NewWriter(file)79	levelstr := getLevel(level)80	str := fmt.Sprintf("%s: [%s] -%v\n", timeStr, levelstr, logMsg)81	_,err = writer.Write([]byte(str))82	if err !=nil {83		return84	}85	err = writer.Flush()86	if err != nil {87		return88	}89	defer file.Close()90}91/*92filelog 93*/94func (flog *FileLog)DeBug(errMsg error) {95	flog.writeTo(DEBUG,errMsg)96}97func (flog *FileLog)Trace(errMsg error){98	flog.writeTo(TRACE,errMsg)99}100func (flog *FileLog)Info(errMgs error){101	flog.writeTo(INFO,errMgs)102}103func (flog *FileLog)Warring(errMsg error){104	flog.writeTo(WARRING,errMsg)105}106func (flog *FileLog)Error(errMsg error){107	flog.writeTo(ERROR,errMsg)108}109func (flog *FileLog)Fatal(errMsg error) {110	flog.writeTo(FATAL,errMsg)		111}112/*consloelog*/113func (clog *ConsoleLog)DeBug(errMsg error){114	clog.writeTo(DEBUG,errMsg)115}116func (clog *ConsoleLog)Trace(errMsg error){117	clog.writeTo(TRACE,errMsg)118}119func (clog *ConsoleLog)Info(errMsg error){120	clog.writeTo(TRACE,errMsg)121}122func (clog *ConsoleLog)Warring(errMsg error){123	clog.writeTo(WARRING,errMsg)124}125func (clog *ConsoleLog)Error(errMsg error){126	clog.writeTo(ERROR,errMsg)127}128func (clog *ConsoleLog)Fatal(errMgs error){129	clog.writeTo(FATAL,errMgs)130}131/*132ç»ç«¯æ¥å¿æå°133*/134func (clog *ConsoleLog)writeTo(level int,errMsg error){135	timeStr := logtime()136	levelstr := getLevel(level)137	fmt.Fprintf(os.Stdout, "%s: [%s] -%v\n", timeStr, levelstr, errMsg)138}...

WriteTo

Using AI Code Generation

1import (2func main() {3    f, err := os.OpenFile("test.log", os.O_RDWR | os.O_CREATE | os.O_APPEND, 0666)4    if err != nil {5        log.Fatalf("error opening file: %v", err)6    }7    defer f.Close()8    log.SetOutput(f)9    log.Println("This is a test log entry")10}11import (12func main() {13    f, err := os.OpenFile("test.log", os.O_RDWR | os.O_CREATE | os.O_APPEND, 0666)14    if err != nil {15        log.Fatalf("error opening file: %v", err)16    }17    defer f.Close()18    log.SetOutput(f)19    log.Println("This is a test log entry")20}21import (22func main() {23    f, err := os.OpenFile("test.log", os.O_RDWR | os.O_CREATE | os.O_APPEND, 0666)24    if err != nil {25        log.Fatalf("error opening file: %v", err)26    }27    defer f.Close()28    log.SetOutput(f)29    log.Println("This is a test log entry")30}31import (32func main() {33    f, err := os.OpenFile("test.log", os.O_RDWR | os.O_CREATE | os.O_APPEND, 0666)34    if err != nil {35        log.Fatalf("error opening file: %v", err)36    }37    defer f.Close()38    log.SetOutput(f)39    log.Println("This is a test log entry")40}41import (42func main() {43    f, err := os.OpenFile("test.log", os.O_RDWR | os.O_CREATE | os.O_APPEND, 0666)44    if err != nil {45        log.Fatalf("error opening file: %v", err)

WriteTo

Using AI Code Generation

1import (2func main() {3	f, err := os.Create("test.txt")4	if err != nil {5		log.Fatal(err)6	}7	defer f.Close()8	log.SetOutput(f)9	log.Println("This is a test log entry")10}

WriteTo

Using AI Code Generation

1import (2func main() {3	file, err := os.OpenFile("log.txt", os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0666)4	if err != nil {5		log.Fatalln("Failed to open log file:", err)6	}7	defer file.Close()8	logger := log.New(file, "logger: ", log.Lshortfile)9	logger.Println("This is a regular message.")10	logger.Fatalln("This is a fatal error.")11}12import (13func main() {14	file, err := os.OpenFile("log.txt", os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0666)15	if err != nil {16		log.Fatalln("Failed to open log file:", err)17	}18	defer file.Close()19	log.SetOutput(file)20	log.Println("This is a regular message.")21	log.Fatalln("This is a fatal error.")22}23import (24func main() {25	log.SetFlags(log.Lshortfile)26	log.Println("This is a regular message.")27	log.Fatalln("This is a fatal error.")28}29import (30func main() {31	log.SetPrefix("logger: ")32	log.Println("This is a regular message.")33	log.Fatalln("This is a fatal error.")34}

WriteTo

Using AI Code Generation

1import (2func main() {3	logfile, err := os.Create("logfile.txt")4	if err != nil {5		log.Fatal(err)6	}7	defer logfile.Close()8	log.SetOutput(logfile)9	log.Println("This is a test log entry")10}

WriteTo

Using AI Code Generation

1import (2func main() {3	f, err := os.OpenFile("log.txt", os.O_CREATE|os.O_WRONLY, 0666)4	if err != nil {5		log.Fatalln("failed to open file: ", err)6	}7	defer f.Close()8	log.SetOutput(f)9	log.Println("This is a regular message")10	log.Fatalln("This is a fatal message")11}12import (13func main() {14	f, err := os.OpenFile("log.txt", os.O_CREATE|os.O_WRONLY, 0666)15	if err != nil {16		log.Fatalln("failed to open file: ", err)17	}18	defer f.Close()19	log.SetOutput(f)20	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)21	log.Println("This is a regular message")22	log.Fatalln("This is a fatal message")23}24import (25func main() {26	f, err := os.OpenFile("log.txt", os.O_CREATE|os.O_WRONLY, 0666)27	if err != nil {28		log.Fatalln("failed to open file: ", err)29	}30	defer f.Close()31	log.SetOutput(f)32	log.SetPrefix("TRACE: ")33	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)34	log.Println("This is a regular message")35	log.Fatalln("This is a fatal message")36}37import (38func main() {39	log.Panicln("This is a panic message")40}41import (42func main() {43	log.Panicf("Hello, %s", name)44}45import (46func main() {47	log.Panic("This is a panic message")48}

WriteTo

Using AI Code Generation

1import (2func main() {3	log.SetOutput(os.Stdout)4	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)5	log.Println("This is a log message")6}7import (8func main() {9	log.SetOutput(os.Stdout)10	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)11	log.Println("This is a log message")12}13How to use log.Fatal() in Go?14How to use log.Panic() in Go?

WriteTo

Using AI Code Generation

1import (2func main() {3	log.SetOutput(os.Stdout)4	log.Println("This is a standard message")5	log.Fatalln("This is a fatal message")6	log.Panicln("This is a panic message")7}8log.Panicln(0xc20800a030, 0x1, 0x1)9main.main()

WriteTo

Using AI Code Generation

1import (2func main() {3	log.SetOutput(os.Stdout)4	log.SetFlags(log.LstdFlags | log.Lshortfile)5	log.Println("This is a test log entry")6	file, err := os.OpenFile("test.log", os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)7	if err == nil {8		log.SetOutput(file)9	} else {10		log.Fatalln("failed to open test.log file for writing")11	}12	log.Println("This is a test log entry")13	log.SetOutput(os.Stdout)14	log.Println("This is a test log entry")15}16func (l *Logger) ReadFrom(r io.Reader) (n int64, err error)17import (18func main() {19	log.SetOutput(os.Stdout)20	log.SetFlags(log.LstdFlags | log.Lshortfile)21	log.Println("This is a test log entry")22	file, err := os.OpenFile("test.log", os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)23	if err == nil {24		log.SetOutput(file)

WriteTo

Using AI Code Generation

1import (2func main() {3	log.SetFlags(0)4	log.SetOutput(os.Stdout)5	log.Println("Hello World")6}7import (8func main() {9	log.SetFlags(0)10	log.SetOutput(os.Stdout)11	log.Println("Hello World")12}13import (14func main() {15	log.SetFlags(0)16	log.SetOutput(os.Stdout)17	log.Println("Hello World")18}19import (20func main() {21	log.SetFlags(0)22	log.SetOutput(os.Stdout)23	log.SetPrefix("Log: ")24	log.Println("Hello World")25}26import (27func main() {28	log.SetFlags(0)29	log.SetOutput(os.Stdout)30	log.SetPrefix("Log: ")31	log.Fatal("Hello World")32}33import (34func main() {35	log.SetFlags(0)36	log.SetOutput(os.Stdout)37	log.SetPrefix("Log: ")38	log.Panic("Hello World")39}40log.Panic(0xc4200b1f78, 0x1, 0x1)

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