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Diffstat (limited to 'vendor/github.com/rs/zerolog/log.go')
| -rw-r--r-- | vendor/github.com/rs/zerolog/log.go | 518 |
1 files changed, 518 insertions, 0 deletions
diff --git a/vendor/github.com/rs/zerolog/log.go b/vendor/github.com/rs/zerolog/log.go new file mode 100644 index 0000000..6c1d4ea --- /dev/null +++ b/vendor/github.com/rs/zerolog/log.go @@ -0,0 +1,518 @@ +// Package zerolog provides a lightweight logging library dedicated to JSON logging. +// +// A global Logger can be use for simple logging: +// +// import "github.com/rs/zerolog/log" +// +// log.Info().Msg("hello world") +// // Output: {"time":1494567715,"level":"info","message":"hello world"} +// +// NOTE: To import the global logger, import the "log" subpackage "github.com/rs/zerolog/log". +// +// Fields can be added to log messages: +// +// log.Info().Str("foo", "bar").Msg("hello world") +// // Output: {"time":1494567715,"level":"info","message":"hello world","foo":"bar"} +// +// Create logger instance to manage different outputs: +// +// logger := zerolog.New(os.Stderr).With().Timestamp().Logger() +// logger.Info(). +// Str("foo", "bar"). +// Msg("hello world") +// // Output: {"time":1494567715,"level":"info","message":"hello world","foo":"bar"} +// +// Sub-loggers let you chain loggers with additional context: +// +// sublogger := log.With().Str("component", "foo").Logger() +// sublogger.Info().Msg("hello world") +// // Output: {"time":1494567715,"level":"info","message":"hello world","component":"foo"} +// +// Level logging +// +// zerolog.SetGlobalLevel(zerolog.InfoLevel) +// +// log.Debug().Msg("filtered out message") +// log.Info().Msg("routed message") +// +// if e := log.Debug(); e.Enabled() { +// // Compute log output only if enabled. +// value := compute() +// e.Str("foo": value).Msg("some debug message") +// } +// // Output: {"level":"info","time":1494567715,"routed message"} +// +// Customize automatic field names: +// +// log.TimestampFieldName = "t" +// log.LevelFieldName = "p" +// log.MessageFieldName = "m" +// +// log.Info().Msg("hello world") +// // Output: {"t":1494567715,"p":"info","m":"hello world"} +// +// Log with no level and message: +// +// log.Log().Str("foo","bar").Msg("") +// // Output: {"time":1494567715,"foo":"bar"} +// +// Add contextual fields to global Logger: +// +// log.Logger = log.With().Str("foo", "bar").Logger() +// +// Sample logs: +// +// sampled := log.Sample(&zerolog.BasicSampler{N: 10}) +// sampled.Info().Msg("will be logged every 10 messages") +// +// Log with contextual hooks: +// +// // Create the hook: +// type SeverityHook struct{} +// +// func (h SeverityHook) Run(e *zerolog.Event, level zerolog.Level, msg string) { +// if level != zerolog.NoLevel { +// e.Str("severity", level.String()) +// } +// } +// +// // And use it: +// var h SeverityHook +// log := zerolog.New(os.Stdout).Hook(h) +// log.Warn().Msg("") +// // Output: {"level":"warn","severity":"warn"} +// +// # Caveats +// +// Field duplication: +// +// There is no fields deduplication out-of-the-box. +// Using the same key multiple times creates new key in final JSON each time. +// +// logger := zerolog.New(os.Stderr).With().Timestamp().Logger() +// logger.Info(). +// Timestamp(). +// Msg("dup") +// // Output: {"level":"info","time":1494567715,"time":1494567715,"message":"dup"} +// +// In this case, many consumers will take the last value, +// but this is not guaranteed; check yours if in doubt. +// +// Concurrency safety: +// +// Be careful when calling UpdateContext. It is not concurrency safe. Use the With method to create a child logger: +// +// func handler(w http.ResponseWriter, r *http.Request) { +// // Create a child logger for concurrency safety +// logger := log.Logger.With().Logger() +// +// // Add context fields, for example User-Agent from HTTP headers +// logger.UpdateContext(func(c zerolog.Context) zerolog.Context { +// ... +// }) +// } +package zerolog + +import ( + "context" + "errors" + "fmt" + "io" + "os" + "strconv" + "strings" +) + +// Level defines log levels. +type Level int8 + +const ( + // DebugLevel defines debug log level. + DebugLevel Level = iota + // InfoLevel defines info log level. + InfoLevel + // WarnLevel defines warn log level. + WarnLevel + // ErrorLevel defines error log level. + ErrorLevel + // FatalLevel defines fatal log level. + FatalLevel + // PanicLevel defines panic log level. + PanicLevel + // NoLevel defines an absent log level. + NoLevel + // Disabled disables the logger. + Disabled + + // TraceLevel defines trace log level. + TraceLevel Level = -1 + // Values less than TraceLevel are handled as numbers. +) + +func (l Level) String() string { + switch l { + case TraceLevel: + return LevelTraceValue + case DebugLevel: + return LevelDebugValue + case InfoLevel: + return LevelInfoValue + case WarnLevel: + return LevelWarnValue + case ErrorLevel: + return LevelErrorValue + case FatalLevel: + return LevelFatalValue + case PanicLevel: + return LevelPanicValue + case Disabled: + return "disabled" + case NoLevel: + return "" + } + return strconv.Itoa(int(l)) +} + +// ParseLevel converts a level string into a zerolog Level value. +// returns an error if the input string does not match known values. +func ParseLevel(levelStr string) (Level, error) { + switch { + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(TraceLevel)): + return TraceLevel, nil + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(DebugLevel)): + return DebugLevel, nil + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(InfoLevel)): + return InfoLevel, nil + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(WarnLevel)): + return WarnLevel, nil + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(ErrorLevel)): + return ErrorLevel, nil + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(FatalLevel)): + return FatalLevel, nil + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(PanicLevel)): + return PanicLevel, nil + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(Disabled)): + return Disabled, nil + case strings.EqualFold(levelStr, LevelFieldMarshalFunc(NoLevel)): + return NoLevel, nil + } + i, err := strconv.Atoi(levelStr) + if err != nil { + return NoLevel, fmt.Errorf("Unknown Level String: '%s', defaulting to NoLevel", levelStr) + } + if i > 127 || i < -128 { + return NoLevel, fmt.Errorf("Out-Of-Bounds Level: '%d', defaulting to NoLevel", i) + } + return Level(i), nil +} + +// UnmarshalText implements encoding.TextUnmarshaler to allow for easy reading from toml/yaml/json formats +func (l *Level) UnmarshalText(text []byte) error { + if l == nil { + return errors.New("can't unmarshal a nil *Level") + } + var err error + *l, err = ParseLevel(string(text)) + return err +} + +// MarshalText implements encoding.TextMarshaler to allow for easy writing into toml/yaml/json formats +func (l Level) MarshalText() ([]byte, error) { + return []byte(LevelFieldMarshalFunc(l)), nil +} + +// A Logger represents an active logging object that generates lines +// of JSON output to an io.Writer. Each logging operation makes a single +// call to the Writer's Write method. There is no guarantee on access +// serialization to the Writer. If your Writer is not thread safe, +// you may consider a sync wrapper. +type Logger struct { + w LevelWriter + level Level + sampler Sampler + context []byte + hooks []Hook + stack bool + ctx context.Context +} + +// New creates a root logger with given output writer. If the output writer implements +// the LevelWriter interface, the WriteLevel method will be called instead of the Write +// one. +// +// Each logging operation makes a single call to the Writer's Write method. There is no +// guarantee on access serialization to the Writer. If your Writer is not thread safe, +// you may consider using sync wrapper. +func New(w io.Writer) Logger { + if w == nil { + w = io.Discard + } + lw, ok := w.(LevelWriter) + if !ok { + lw = LevelWriterAdapter{w} + } + return Logger{w: lw, level: TraceLevel} +} + +// Nop returns a disabled logger for which all operation are no-op. +func Nop() Logger { + return New(nil).Level(Disabled) +} + +// Output duplicates the current logger and sets w as its output. +func (l Logger) Output(w io.Writer) Logger { + l2 := New(w) + l2.level = l.level + l2.sampler = l.sampler + l2.stack = l.stack + if len(l.hooks) > 0 { + l2.hooks = append(l2.hooks, l.hooks...) + } + if l.context != nil { + l2.context = make([]byte, len(l.context), cap(l.context)) + copy(l2.context, l.context) + } + return l2 +} + +// With creates a child logger with the field added to its context. +func (l Logger) With() Context { + context := l.context + l.context = make([]byte, 0, 500) + if context != nil { + l.context = append(l.context, context...) + } else { + // This is needed for AppendKey to not check len of input + // thus making it inlinable + l.context = enc.AppendBeginMarker(l.context) + } + return Context{l} +} + +// UpdateContext updates the internal logger's context. +// +// Caution: This method is not concurrency safe. +// Use the With method to create a child logger before modifying the context from concurrent goroutines. +func (l *Logger) UpdateContext(update func(c Context) Context) { + if l == disabledLogger { + return + } + if cap(l.context) == 0 { + l.context = make([]byte, 0, 500) + } + if len(l.context) == 0 { + l.context = enc.AppendBeginMarker(l.context) + } + c := update(Context{*l}) + l.context = c.l.context +} + +// Level creates a child logger with the minimum accepted level set to level. +func (l Logger) Level(lvl Level) Logger { + l.level = lvl + return l +} + +// GetLevel returns the current Level of l. +func (l Logger) GetLevel() Level { + return l.level +} + +// Sample returns a logger with the s sampler. +func (l Logger) Sample(s Sampler) Logger { + l.sampler = s + return l +} + +// Hook returns a logger with the h Hook. +func (l Logger) Hook(hooks ...Hook) Logger { + if len(hooks) == 0 { + return l + } + newHooks := make([]Hook, len(l.hooks), len(l.hooks)+len(hooks)) + copy(newHooks, l.hooks) + l.hooks = append(newHooks, hooks...) + return l +} + +// Trace starts a new message with trace level. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Trace() *Event { + return l.newEvent(TraceLevel, nil) +} + +// Debug starts a new message with debug level. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Debug() *Event { + return l.newEvent(DebugLevel, nil) +} + +// Info starts a new message with info level. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Info() *Event { + return l.newEvent(InfoLevel, nil) +} + +// Warn starts a new message with warn level. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Warn() *Event { + return l.newEvent(WarnLevel, nil) +} + +// Error starts a new message with error level. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Error() *Event { + return l.newEvent(ErrorLevel, nil) +} + +// Err starts a new message with error level with err as a field if not nil or +// with info level if err is nil. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Err(err error) *Event { + if err != nil { + return l.Error().Err(err) + } + + return l.Info() +} + +// Fatal starts a new message with fatal level. The os.Exit(1) function +// is called by the Msg method, which terminates the program immediately. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Fatal() *Event { + return l.newEvent(FatalLevel, func(msg string) { + if closer, ok := l.w.(io.Closer); ok { + // Close the writer to flush any buffered message. Otherwise the message + // will be lost as os.Exit() terminates the program immediately. + closer.Close() + } + os.Exit(1) + }) +} + +// Panic starts a new message with panic level. The panic() function +// is called by the Msg method, which stops the ordinary flow of a goroutine. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Panic() *Event { + return l.newEvent(PanicLevel, func(msg string) { panic(msg) }) +} + +// WithLevel starts a new message with level. Unlike Fatal and Panic +// methods, WithLevel does not terminate the program or stop the ordinary +// flow of a goroutine when used with their respective levels. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) WithLevel(level Level) *Event { + switch level { + case TraceLevel: + return l.Trace() + case DebugLevel: + return l.Debug() + case InfoLevel: + return l.Info() + case WarnLevel: + return l.Warn() + case ErrorLevel: + return l.Error() + case FatalLevel: + return l.newEvent(FatalLevel, nil) + case PanicLevel: + return l.newEvent(PanicLevel, nil) + case NoLevel: + return l.Log() + case Disabled: + return nil + default: + return l.newEvent(level, nil) + } +} + +// Log starts a new message with no level. Setting GlobalLevel to Disabled +// will still disable events produced by this method. +// +// You must call Msg on the returned event in order to send the event. +func (l *Logger) Log() *Event { + return l.newEvent(NoLevel, nil) +} + +// Print sends a log event using debug level and no extra field. +// Arguments are handled in the manner of fmt.Print. +func (l *Logger) Print(v ...interface{}) { + if e := l.Debug(); e.Enabled() { + e.CallerSkipFrame(1).Msg(fmt.Sprint(v...)) + } +} + +// Printf sends a log event using debug level and no extra field. +// Arguments are handled in the manner of fmt.Printf. +func (l *Logger) Printf(format string, v ...interface{}) { + if e := l.Debug(); e.Enabled() { + e.CallerSkipFrame(1).Msg(fmt.Sprintf(format, v...)) + } +} + +// Println sends a log event using debug level and no extra field. +// Arguments are handled in the manner of fmt.Println. +func (l *Logger) Println(v ...interface{}) { + if e := l.Debug(); e.Enabled() { + e.CallerSkipFrame(1).Msg(fmt.Sprintln(v...)) + } +} + +// Write implements the io.Writer interface. This is useful to set as a writer +// for the standard library log. +func (l Logger) Write(p []byte) (n int, err error) { + n = len(p) + if n > 0 && p[n-1] == '\n' { + // Trim CR added by stdlog. + p = p[0 : n-1] + } + l.Log().CallerSkipFrame(1).Msg(string(p)) + return +} + +func (l *Logger) newEvent(level Level, done func(string)) *Event { + enabled := l.should(level) + if !enabled { + if done != nil { + done("") + } + return nil + } + e := newEvent(l.w, level) + e.done = done + e.ch = l.hooks + e.ctx = l.ctx + if level != NoLevel && LevelFieldName != "" { + e.Str(LevelFieldName, LevelFieldMarshalFunc(level)) + } + if l.context != nil && len(l.context) > 1 { + e.buf = enc.AppendObjectData(e.buf, l.context) + } + if l.stack { + e.Stack() + } + return e +} + +// should returns true if the log event should be logged. +func (l *Logger) should(lvl Level) bool { + if l.w == nil { + return false + } + if lvl < l.level || lvl < GlobalLevel() { + return false + } + if l.sampler != nil && !samplingDisabled() { + return l.sampler.Sample(lvl) + } + return true +} |
