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How to use New method of log Package
Best Testkube code snippet using log.New
syslog.go
Source:syslog.go 
...85type netConn struct {86 local bool87 conn net.Conn88}89// New establishes a new connection to the system log daemon. Each90// write to the returned writer sends a log message with the given91// priority and prefix.92func New(priority Priority, tag string) (w *Writer, err error) {93 return Dial("", "", priority, tag)94}95// Dial establishes a connection to a log daemon by connecting to96// address raddr on the specified network. Each write to the returned97// writer sends a log message with the given facility, severity and98// tag.99// If network is empty, Dial will connect to the local syslog server.100func Dial(network, raddr string, priority Priority, tag string) (*Writer, error) {101 if priority < 0 || priority > LOG_LOCAL7|LOG_DEBUG {102 return nil, errors.New("log/syslog: invalid priority")103 }104 if tag == "" {105 tag = os.Args[0]106 }107 hostname, _ := os.Hostname()108 w := &Writer{109 priority: priority,110 tag: tag,111 hostname: hostname,112 network: network,113 raddr: raddr,114 }115 w.mu.Lock()116 defer w.mu.Unlock()117 err := w.connect()118 if err != nil {119 return nil, err120 }121 return w, err122}123// connect makes a connection to the syslog server.124// It must be called with w.mu held.125func (w *Writer) connect() (err error) {126 if w.conn != nil {127 // ignore err from close, it makes sense to continue anyway128 w.conn.close()129 w.conn = nil130 }131 if w.network == "" {132 w.conn, err = unixSyslog()133 if w.hostname == "" {134 w.hostname = "localhost"135 }136 } else {137 var c net.Conn138 c, err = net.Dial(w.network, w.raddr)139 if err == nil {140 w.conn = &netConn{conn: c}141 if w.hostname == "" {142 w.hostname = c.LocalAddr().String()143 }144 }145 }146 return147}148// Write sends a log message to the syslog daemon.149func (w *Writer) Write(b []byte) (int, error) {150 return w.writeAndRetry(w.priority, string(b))151}152// Close closes a connection to the syslog daemon.153func (w *Writer) Close() error {154 w.mu.Lock()155 defer w.mu.Unlock()156 if w.conn != nil {157 err := w.conn.close()158 w.conn = nil159 return err160 }161 return nil162}163// Emerg logs a message with severity LOG_EMERG, ignoring the severity164// passed to New.165func (w *Writer) Emerg(m string) (err error) {166 _, err = w.writeAndRetry(LOG_EMERG, m)167 return err168}169// Alert logs a message with severity LOG_ALERT, ignoring the severity170// passed to New.171func (w *Writer) Alert(m string) (err error) {172 _, err = w.writeAndRetry(LOG_ALERT, m)173 return err174}175// Crit logs a message with severity LOG_CRIT, ignoring the severity176// passed to New.177func (w *Writer) Crit(m string) (err error) {178 _, err = w.writeAndRetry(LOG_CRIT, m)179 return err180}181// Err logs a message with severity LOG_ERR, ignoring the severity182// passed to New.183func (w *Writer) Err(m string) (err error) {184 _, err = w.writeAndRetry(LOG_ERR, m)185 return err186}187// Warning logs a message with severity LOG_WARNING, ignoring the188// severity passed to New.189func (w *Writer) Warning(m string) (err error) {190 _, err = w.writeAndRetry(LOG_WARNING, m)191 return err192}193// Notice logs a message with severity LOG_NOTICE, ignoring the194// severity passed to New.195func (w *Writer) Notice(m string) (err error) {196 _, err = w.writeAndRetry(LOG_NOTICE, m)197 return err198}199// Info logs a message with severity LOG_INFO, ignoring the severity200// passed to New.201func (w *Writer) Info(m string) (err error) {202 _, err = w.writeAndRetry(LOG_INFO, m)203 return err204}205// Debug logs a message with severity LOG_DEBUG, ignoring the severity206// passed to New.207func (w *Writer) Debug(m string) (err error) {208 _, err = w.writeAndRetry(LOG_DEBUG, m)209 return err210}211func (w *Writer) writeAndRetry(p Priority, s string) (int, error) {212 pr := (w.priority & facilityMask) | (p & severityMask)213 w.mu.Lock()214 defer w.mu.Unlock()215 if w.conn != nil {216 if n, err := w.write(pr, s); err == nil {217 return n, err218 }219 }220 if err := w.connect(); err != nil {221 return 0, err222 }223 return w.write(pr, s)224}225// write generates and writes a syslog formatted string. The226// format is as follows: <PRI>TIMESTAMP HOSTNAME TAG[PID]: MSG227func (w *Writer) write(p Priority, msg string) (int, error) {228 // ensure it ends in a \n229 nl := ""230 if !strings.HasSuffix(msg, "\n") {231 nl = "\n"232 }233 err := w.conn.writeString(p, w.hostname, w.tag, msg, nl)234 if err != nil {235 return 0, err236 }237 // Note: return the length of the input, not the number of238 // bytes printed by Fprintf, because this must behave like239 // an io.Writer.240 return len(msg), nil241}242func (n *netConn) writeString(p Priority, hostname, tag, msg, nl string) error {243 if n.local {244 // Compared to the network form below, the changes are:245 // 1. Use time.Stamp instead of time.RFC3339.246 // 2. Drop the hostname field from the Fprintf.247 timestamp := time.Now().Format(time.Stamp)248 _, err := fmt.Fprintf(n.conn, "<%d>%s %s[%d]: %s%s",249 p, timestamp,250 tag, os.Getpid(), msg, nl)251 return err252 }253 timestamp := time.Now().Format(time.RFC3339)254 _, err := fmt.Fprintf(n.conn, "<%d>%s %s %s[%d]: %s%s",255 p, timestamp, hostname,256 tag, os.Getpid(), msg, nl)257 return err258}259func (n *netConn) close() error {260 return n.conn.Close()261}262// NewLogger creates a log.Logger whose output is written to263// the system log service with the specified priority. The logFlag264// argument is the flag set passed through to log.New to create265// the Logger.266func NewLogger(p Priority, logFlag int) (*log.Logger, error) {267 s, err := New(p, "")268 if err != nil {269 return nil, err270 }271 return log.New(s, "", logFlag), nil272}...
monitor_test.go
Source:monitor_test.go
...7 "github.com/stretchr/testify/require"8)9func TestMonitor_Start(t *testing.T) {10 t.Parallel()11 require := require.New(t)12 logger := log.NewInterceptLogger(&log.LoggerOptions{13 Level: log.Error,14 })15 m := New(Config{16 BufferSize: 512,17 Logger: logger,18 LoggerOptions: &log.LoggerOptions{19 Level: log.Debug},20 })21 logCh := m.Start()22 defer m.Stop()23 logger.Debug("test log")24 for {25 select {26 case log := <-logCh:27 require.Contains(string(log), "[DEBUG] test log")28 return29 case <-time.After(3 * time.Second):30 t.Fatal("Expected to receive from log channel")31 }32 }33}34func TestMonitor_Stop(t *testing.T) {35 t.Parallel()36 require := require.New(t)37 logger := log.NewInterceptLogger(&log.LoggerOptions{38 Level: log.Error,39 })40 m := New(Config{41 BufferSize: 512,42 Logger: logger,43 LoggerOptions: &log.LoggerOptions{44 Level: log.Debug,45 },46 })47 logCh := m.Start()48 logger.Debug("test log")49 require.Eventually(func() bool {50 return len(logCh) == 151 }, 3*time.Second, 100*time.Millisecond, "expected logCh to have 1 log in it")52 m.Stop()53 // This log line should not be output to the log channel54 logger.Debug("After Stop")55 for {56 select {57 case log := <-logCh:58 if string(log) != "" {59 require.Contains(string(log), "[DEBUG] test log")60 } else {61 return62 }63 case <-time.After(3 * time.Second):64 t.Fatal("Expected to receive from log channel")65 }66 }67}68func TestMonitor_DroppedMessages(t *testing.T) {69 t.Parallel()70 require := require.New(t)71 logger := log.NewInterceptLogger(&log.LoggerOptions{72 Level: log.Warn,73 })74 mcfg := Config{75 BufferSize: 5,76 Logger: logger,77 LoggerOptions: &log.LoggerOptions{78 Level: log.Debug,79 },80 }81 m := New(mcfg)82 doneCh := make(chan struct{})83 defer close(doneCh)84 logCh := m.Start()85 // Overflow the configured buffer size before we attempt to receive from the86 // logCh. We choose (2*bufSize+1) to account for:87 // - buffer size of internal write channel88 // - buffer size of channel returned from Start()89 // - A message guaranteed to be dropped because all buffers are full90 for i := 0; i <= 2*mcfg.BufferSize+1; i++ {91 logger.Debug(fmt.Sprintf("test message %d", i))92 }93 // Make sure we do not stop before the goroutines have time to process.94 require.Eventually(func() bool {95 return len(logCh) == mcfg.BufferSize96 }, 3*time.Second, 100*time.Millisecond, "expected logCh to have a full log buffer")97 dropped := m.Stop()98 // The number of dropped messages is non-deterministic, so we only assert99 // that we dropped at least 1.100 require.GreaterOrEqual(dropped, 1)101}102func TestMonitor_ZeroBufSizeDefault(t *testing.T) {103 t.Parallel()104 require := require.New(t)105 logger := log.NewInterceptLogger(&log.LoggerOptions{106 Level: log.Error,107 })108 m := New(Config{109 BufferSize: 0,110 Logger: logger,111 LoggerOptions: &log.LoggerOptions{112 Level: log.Debug,113 },114 })115 logCh := m.Start()116 defer m.Stop()117 logger.Debug("test log")118 // If we do not default the buffer size, the monitor will be unable to buffer119 // a log line.120 require.Eventually(func() bool {121 return len(logCh) == 1122 }, 3*time.Second, 100*time.Millisecond, "expected logCh to have 1 log buffered")123 for {124 select {125 case log := <-logCh:126 require.Contains(string(log), "[DEBUG] test log")127 return128 case <-time.After(3 * time.Second):129 t.Fatal("Expected to receive from log channel")130 }131 }132}133func TestMonitor_WriteStopped(t *testing.T) {134 t.Parallel()135 require := require.New(t)136 logger := log.NewInterceptLogger(&log.LoggerOptions{137 Level: log.Error,138 })139 mwriter := &monitor{140 logger: logger,141 doneCh: make(chan struct{}, 1),142 }143 mwriter.Stop()144 n, err := mwriter.Write([]byte("write after close"))145 require.Equal(n, 0)146 require.EqualError(err, "monitor stopped")147}...
debug.go
Source:debug.go
...31)32// Run micro debug33func Run(ctx *cli.Context) error {34 // new service35 srv := service.New(36 service.Name(name),37 service.Address(address),38 )39 // default log initialiser40 newLog := func(service string) log.Log {41 // service log calls the actual service for the log42 return dservice.NewLog(43 // log with service name44 log.Name(service),45 )46 }47 source := ctx.String("log")48 switch source {49 case "service":50 newLog = func(service string) log.Log {51 return dservice.NewLog(52 log.Name(service),53 )54 }55 case "kubernetes":56 newLog = func(service string) log.Log {57 return kubernetes.NewLog(58 log.Name(service),59 )60 }61 }62 done := make(chan bool)63 defer func() {64 close(done)65 }()66 // create a service cache67 c := newCache(done)68 // log handler69 lgHandler := &logHandler.Log{70 // create the log map71 Logs: make(map[string]log.Log),72 // Create the new func73 New: newLog,74 }75 // Register the logs handler76 pblog.RegisterLogHandler(srv.Server(), lgHandler)77 // stats handler78 statsHandler, err := statshandler.New(done, ctx.Int("window"), c.services)79 if err != nil {80 logger.Fatal(err)81 }82 // stats handler83 traceHandler, err := tracehandler.New(done, ctx.Int("window"), c.services)84 if err != nil {85 logger.Fatal(err)86 }87 // Register the stats handler88 pbstats.RegisterStatsHandler(srv.Server(), statsHandler)89 // register trace handler90 pbtrace.RegisterTraceHandler(srv.Server(), traceHandler)91 // TODO: implement debug service for k8s cruft92 // start debug service93 if err := srv.Run(); err != nil {94 logger.Fatal(err)95 }96 return nil97}...
New
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.SetFlags(log.LstdFlags | log.Lshortfile)10 log.Println("This is a test log entry")11}12log.LstdFlags: Ldate | Ltime (initial values for the standard logger)
New
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}11log.SetPrefix()12import (13func main() {14 f, err := os.OpenFile("test.log", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)15 if err != nil {16 log.Fatalf("error opening file: %v", err)17 }18 defer f.Close()19 log.SetOutput(f)20 log.SetPrefix("TRACE: ")21 log.Println("This is a test log entry")22}23log.SetFlags()24import (25func main() {26 f, err := os.OpenFile("test.log", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
New
Using AI Code Generation
1log.New(os.Stdout, "logger: ", log.Lshortfile)2log.New(os.Stdout, "logger: ", log.Lshortfile)3log.New(os.Stdout, "logger: ", log.Lshortfile)4log.New(os.Stdout, "logger: ", log.Lshortfile)5log.New(os.Stdout, "logger: ", log.Lshortfile)6log.New(os.Stdout, "logger: ", log.Lshortfile)7log.New(os.Stdout, "logger: ", log.Lshortfile)8log.New(os.Stdout, "logger: ", log.Lshortfile)9log.New(os.Stdout, "logger: ", log.Lshortfile)10log.New(os.Stdout, "logger: ", log.Lshortfile)11log.New(os.Stdout, "logger: ", log.Lshortfile)12log.New(os.Stdout, "logger: ", log.Lshortfile)13log.New(os.Stdout, "logger: ", log.Lshortfile)14log.New(os.Stdout, "logger: ", log.Lshortfile)15log.New(os.Stdout, "logger: ", log.Lshortfile)16log.New(os.Stdout, "logger: ", log.Lshortfile)
New
Using AI Code Generation
1import (2func main() {3 f, err := os.Create("test.log")4 if err != nil {5 log.Fatal(err)6 }7 defer func() {8 if err := f.Close(); err != nil {9 log.Fatal(err)10 }11 }()12 log.SetOutput(f)13 log.Print("This is a log message")14}15import (16func main() {17 f, err := os.Create("test.log")18 if err != nil {19 log.Fatal(err)20 }21 defer func() {22 if err := f.Close(); err != nil {23 log.Fatal(err)24 }25 }()26 logger := log.New(f, "logger: ", log.Lshortfile)27 logger.Print("This is a log message")28}29import (30func main() {31 f, err := os.Create("test.log")32 if err != nil {33 log.Fatal(err)34 }35 defer func() {36 if err := f.Close(); err != nil {37 log.Fatal(err)38 }39 }()40 logger := log.New(f, "logger: ", log.Lshortfile)41 logger.Print("This is a log message")42 logger2 := log.New(os.Stdout, "logger2: ", log.Lshortfile)
New
Using AI Code Generation
1import (2func main() {3 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)4}5import (6func main() {7 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)8}9import (10func main() {11 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)12}13import (14func main() {15 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)16}17import (18func main() {19 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)20}21import (22func main() {23 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)24}25import (26func main() {27 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)28}29import (30func main() {31 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)32}33import (34func main() {35 log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)36}
New
Using AI Code Generation
1import (2func main() {3 log.New(os.Stdout, "prefix: ", log.Ldate|log.Ltime|log.Lshortfile)4}5import (6func main() {7 log.Println("Hello World!")8}9import (10func main() {11 log.Fatalln("Hello World!")12}13import (14func main() {15 log.Panicln("Hello World!")16}17import (18func main() {19 log.Println(log.Flags())20}21import (22func main() {23 log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)24}25import (26func main() {27 log.Output(2, "Hello World!")28}29import (30func main() {31 log.Println(log.Prefix())32}33import (34func main() {35 log.SetPrefix("prefix: ")36}37import (38func main() {39 log.Println(log.Writer())40}41import (42func main() {43 log.SetOutput(os.Stdout)44}45import (46func main() {47 log.Print("Hello World!")48}
New
Using AI Code Generation
1import (2func main() {3 logger := log.New(os.Stderr, "logger: ", log.Ldate|log.Ltime|log.Lshortfile)4 logger.Println("Hello, log file!")5}6import (7func main() {8 log.Fatal("Hello, log file!")9}10import (11func main() {12 log.Fatalf("Hello, %s!", "log file")13}14import (15func main() {16 log.Fatalln("Hello, log file!")17}18import (19func main() {20 log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)21 log.Println("Hello, log file!")22}23import (24func main() {25 log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)26 log.Output(2, "Hello, log file!")27}28import (29func main() {30 log.Panic("Hello, log file!")31}32import (33func main() {34 log.Panicf("Hello, %s!", "log file")35}36import (37func main() {38 log.Panicln("
New
Using AI Code Generation
1import "log"2func main() {3 logger := log.New(os.Stdout, "example ", log.LstdFlags|log.Lshortfile)4 logger.SetPrefix("example ")5 logger.SetFlags(log.LstdFlags | log.Lshortfile)6 logger.Println("message")7 logger.Printf("message with %s format", "printf")8}9import "log"10func main() {11 log.Println("message")12 log.Printf("message with %s format", "printf")13}14import "log"15func main() {16 log.Fatal("message")17 log.Fatalf("message with %s format", "printf")18}19import "log"20func main() {21 log.Panic("message")22 log.Panicf("message with %s format", "printf")23}24log.Panic(0xc0000b3f78,
New
Using AI Code Generation
1func main() {2 log.New(os.Stdout, "prefix: ", log.Ldate|log.Ltime|log.Lshortfile)3}4func main() {5 log.SetOutput(os.Stdout)6 log.SetPrefix("prefix: ")7 log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)8}9func main() {10 log.SetOutput(os.Stdout)11 log.SetPrefix("prefix: ")12 log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)13 log.Println("Hello World")14}15func main() {16 log.SetOutput(os.Stdout)17 log.SetPrefix("prefix: ")18 log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)19 log.Printf("Hello %s", "World")20}21func main() {22 log.SetOutput(os.Stdout)23 log.SetPrefix("prefix: ")24 log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)25 log.Fatal("Hello World
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