source: code/trunk/vendor/github.com/sirupsen/logrus/logger.go@ 67

package logrus

import (
        "context"
        "io"
        "os"
        "sync"
        "sync/atomic"
        "time"
)

// LogFunction For big messages, it can be more efficient to pass a function
// and only call it if the log level is actually enables rather than
// generating the log message and then checking if the level is enabled
type LogFunction func() []interface{}

type Logger struct {
        // The logs are `io.Copy`'d to this in a mutex. It's common to set this to a
        // file, or leave it default which is `os.Stderr`. You can also set this to
        // something more adventurous, such as logging to Kafka.
        Out io.Writer
        // Hooks for the logger instance. These allow firing events based on logging
        // levels and log entries. For example, to send errors to an error tracking
        // service, log to StatsD or dump the core on fatal errors.
        Hooks LevelHooks
        // All log entries pass through the formatter before logged to Out. The
        // included formatters are `TextFormatter` and `JSONFormatter` for which
        // TextFormatter is the default. In development (when a TTY is attached) it
        // logs with colors, but to a file it wouldn't. You can easily implement your
        // own that implements the `Formatter` interface, see the `README` or included
        // formatters for examples.
        Formatter Formatter

        // Flag for whether to log caller info (off by default)
        ReportCaller bool

        // The logging level the logger should log at. This is typically (and defaults
        // to) `logrus.Info`, which allows Info(), Warn(), Error() and Fatal() to be
        // logged.
        Level Level
        // Used to sync writing to the log. Locking is enabled by Default
        mu MutexWrap
        // Reusable empty entry
        entryPool sync.Pool
        // Function to exit the application, defaults to `os.Exit()`
        ExitFunc exitFunc
        // The buffer pool used to format the log. If it is nil, the default global
        // buffer pool will be used.
        BufferPool BufferPool
}

type exitFunc func(int)

type MutexWrap struct {
        lock     sync.Mutex
        disabled bool
}

func (mw *MutexWrap) Lock() {
        if !mw.disabled {
                mw.lock.Lock()
        }
}

func (mw *MutexWrap) Unlock() {
        if !mw.disabled {
                mw.lock.Unlock()
        }
}

func (mw *MutexWrap) Disable() {
        mw.disabled = true
}

// Creates a new logger. Configuration should be set by changing `Formatter`,
// `Out` and `Hooks` directly on the default logger instance. You can also just
// instantiate your own:
//
//    var log = &logrus.Logger{
//      Out: os.Stderr,
//      Formatter: new(logrus.TextFormatter),
//      Hooks: make(logrus.LevelHooks),
//      Level: logrus.DebugLevel,
//    }
//
// It's recommended to make this a global instance called `log`.
func New() *Logger {
        return &Logger{
                Out:          os.Stderr,
                Formatter:    new(TextFormatter),
                Hooks:        make(LevelHooks),
                Level:        InfoLevel,
                ExitFunc:     os.Exit,
                ReportCaller: false,
        }
}

func (logger *Logger) newEntry() *Entry {
        entry, ok := logger.entryPool.Get().(*Entry)
        if ok {
                return entry
        }
        return NewEntry(logger)
}

func (logger *Logger) releaseEntry(entry *Entry) {
        entry.Data = map[string]interface{}{}
        logger.entryPool.Put(entry)
}

// WithField allocates a new entry and adds a field to it.
// Debug, Print, Info, Warn, Error, Fatal or Panic must be then applied to
// this new returned entry.
// If you want multiple fields, use `WithFields`.
func (logger *Logger) WithField(key string, value interface{}) *Entry {
        entry := logger.newEntry()
        defer logger.releaseEntry(entry)
        return entry.WithField(key, value)
}

// Adds a struct of fields to the log entry. All it does is call `WithField` for
// each `Field`.
func (logger *Logger) WithFields(fields Fields) *Entry {
        entry := logger.newEntry()
        defer logger.releaseEntry(entry)
        return entry.WithFields(fields)
}

// Add an error as single field to the log entry.  All it does is call
// `WithError` for the given `error`.
func (logger *Logger) WithError(err error) *Entry {
        entry := logger.newEntry()
        defer logger.releaseEntry(entry)
        return entry.WithError(err)
}

// Add a context to the log entry.
func (logger *Logger) WithContext(ctx context.Context) *Entry {
        entry := logger.newEntry()
        defer logger.releaseEntry(entry)
        return entry.WithContext(ctx)
}

// Overrides the time of the log entry.
func (logger *Logger) WithTime(t time.Time) *Entry {
        entry := logger.newEntry()
        defer logger.releaseEntry(entry)
        return entry.WithTime(t)
}

func (logger *Logger) Logf(level Level, format string, args ...interface{}) {
        if logger.IsLevelEnabled(level) {
                entry := logger.newEntry()
                entry.Logf(level, format, args...)
                logger.releaseEntry(entry)
        }
}

func (logger *Logger) Tracef(format string, args ...interface{}) {
        logger.Logf(TraceLevel, format, args...)
}

func (logger *Logger) Debugf(format string, args ...interface{}) {
        logger.Logf(DebugLevel, format, args...)
}

func (logger *Logger) Infof(format string, args ...interface{}) {
        logger.Logf(InfoLevel, format, args...)
}

func (logger *Logger) Printf(format string, args ...interface{}) {
        entry := logger.newEntry()
        entry.Printf(format, args...)
        logger.releaseEntry(entry)
}

func (logger *Logger) Warnf(format string, args ...interface{}) {
        logger.Logf(WarnLevel, format, args...)
}

func (logger *Logger) Warningf(format string, args ...interface{}) {
        logger.Warnf(format, args...)
}

func (logger *Logger) Errorf(format string, args ...interface{}) {
        logger.Logf(ErrorLevel, format, args...)
}

func (logger *Logger) Fatalf(format string, args ...interface{}) {
        logger.Logf(FatalLevel, format, args...)
        logger.Exit(1)
}

func (logger *Logger) Panicf(format string, args ...interface{}) {
        logger.Logf(PanicLevel, format, args...)
}

// Log will log a message at the level given as parameter.
// Warning: using Log at Panic or Fatal level will not respectively Panic nor Exit.
// For this behaviour Logger.Panic or Logger.Fatal should be used instead.
func (logger *Logger) Log(level Level, args ...interface{}) {
        if logger.IsLevelEnabled(level) {
                entry := logger.newEntry()
                entry.Log(level, args...)
                logger.releaseEntry(entry)
        }
}

func (logger *Logger) LogFn(level Level, fn LogFunction) {
        if logger.IsLevelEnabled(level) {
                entry := logger.newEntry()
                entry.Log(level, fn()...)
                logger.releaseEntry(entry)
        }
}

func (logger *Logger) Trace(args ...interface{}) {
        logger.Log(TraceLevel, args...)
}

func (logger *Logger) Debug(args ...interface{}) {
        logger.Log(DebugLevel, args...)
}

func (logger *Logger) Info(args ...interface{}) {
        logger.Log(InfoLevel, args...)
}

func (logger *Logger) Print(args ...interface{}) {
        entry := logger.newEntry()
        entry.Print(args...)
        logger.releaseEntry(entry)
}

func (logger *Logger) Warn(args ...interface{}) {
        logger.Log(WarnLevel, args...)
}

func (logger *Logger) Warning(args ...interface{}) {
        logger.Warn(args...)
}

func (logger *Logger) Error(args ...interface{}) {
        logger.Log(ErrorLevel, args...)
}

func (logger *Logger) Fatal(args ...interface{}) {
        logger.Log(FatalLevel, args...)
        logger.Exit(1)
}

func (logger *Logger) Panic(args ...interface{}) {
        logger.Log(PanicLevel, args...)
}

func (logger *Logger) TraceFn(fn LogFunction) {
        logger.LogFn(TraceLevel, fn)
}

func (logger *Logger) DebugFn(fn LogFunction) {
        logger.LogFn(DebugLevel, fn)
}

func (logger *Logger) InfoFn(fn LogFunction) {
        logger.LogFn(InfoLevel, fn)
}

func (logger *Logger) PrintFn(fn LogFunction) {
        entry := logger.newEntry()
        entry.Print(fn()...)
        logger.releaseEntry(entry)
}

func (logger *Logger) WarnFn(fn LogFunction) {
        logger.LogFn(WarnLevel, fn)
}

func (logger *Logger) WarningFn(fn LogFunction) {
        logger.WarnFn(fn)
}

func (logger *Logger) ErrorFn(fn LogFunction) {
        logger.LogFn(ErrorLevel, fn)
}

func (logger *Logger) FatalFn(fn LogFunction) {
        logger.LogFn(FatalLevel, fn)
        logger.Exit(1)
}

func (logger *Logger) PanicFn(fn LogFunction) {
        logger.LogFn(PanicLevel, fn)
}

func (logger *Logger) Logln(level Level, args ...interface{}) {
        if logger.IsLevelEnabled(level) {
                entry := logger.newEntry()
                entry.Logln(level, args...)
                logger.releaseEntry(entry)
        }
}

func (logger *Logger) Traceln(args ...interface{}) {
        logger.Logln(TraceLevel, args...)
}

func (logger *Logger) Debugln(args ...interface{}) {
        logger.Logln(DebugLevel, args...)
}

func (logger *Logger) Infoln(args ...interface{}) {
        logger.Logln(InfoLevel, args...)
}

func (logger *Logger) Println(args ...interface{}) {
        entry := logger.newEntry()
        entry.Println(args...)
        logger.releaseEntry(entry)
}

func (logger *Logger) Warnln(args ...interface{}) {
        logger.Logln(WarnLevel, args...)
}

func (logger *Logger) Warningln(args ...interface{}) {
        logger.Warnln(args...)
}

func (logger *Logger) Errorln(args ...interface{}) {
        logger.Logln(ErrorLevel, args...)
}

func (logger *Logger) Fatalln(args ...interface{}) {
        logger.Logln(FatalLevel, args...)
        logger.Exit(1)
}

func (logger *Logger) Panicln(args ...interface{}) {
        logger.Logln(PanicLevel, args...)
}

func (logger *Logger) Exit(code int) {
        runHandlers()
        if logger.ExitFunc == nil {
                logger.ExitFunc = os.Exit
        }
        logger.ExitFunc(code)
}

//When file is opened with appending mode, it's safe to
//write concurrently to a file (within 4k message on Linux).
//In these cases user can choose to disable the lock.
func (logger *Logger) SetNoLock() {
        logger.mu.Disable()
}

func (logger *Logger) level() Level {
        return Level(atomic.LoadUint32((*uint32)(&logger.Level)))
}

// SetLevel sets the logger level.
func (logger *Logger) SetLevel(level Level) {
        atomic.StoreUint32((*uint32)(&logger.Level), uint32(level))
}

// GetLevel returns the logger level.
func (logger *Logger) GetLevel() Level {
        return logger.level()
}

// AddHook adds a hook to the logger hooks.
func (logger *Logger) AddHook(hook Hook) {
        logger.mu.Lock()
        defer logger.mu.Unlock()
        logger.Hooks.Add(hook)
}

// IsLevelEnabled checks if the log level of the logger is greater than the level param
func (logger *Logger) IsLevelEnabled(level Level) bool {
        return logger.level() >= level
}

// SetFormatter sets the logger formatter.
func (logger *Logger) SetFormatter(formatter Formatter) {
        logger.mu.Lock()
        defer logger.mu.Unlock()
        logger.Formatter = formatter
}

// SetOutput sets the logger output.
func (logger *Logger) SetOutput(output io.Writer) {
        logger.mu.Lock()
        defer logger.mu.Unlock()
        logger.Out = output
}

func (logger *Logger) SetReportCaller(reportCaller bool) {
        logger.mu.Lock()
        defer logger.mu.Unlock()
        logger.ReportCaller = reportCaller
}

// ReplaceHooks replaces the logger hooks and returns the old ones
func (logger *Logger) ReplaceHooks(hooks LevelHooks) LevelHooks {
        logger.mu.Lock()
        oldHooks := logger.Hooks
        logger.Hooks = hooks
        logger.mu.Unlock()
        return oldHooks
}

// SetBufferPool sets the logger buffer pool.
func (logger *Logger) SetBufferPool(pool BufferPool) {
        logger.mu.Lock()
        defer logger.mu.Unlock()
        logger.BufferPool = pool
}