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diff --git a/vendor/gopkg.in/natefinch/lumberjack.v2/README.md b/vendor/gopkg.in/natefinch/lumberjack.v2/README.md new file mode 100644 index 000000000..9e9715453 --- /dev/null +++ b/vendor/gopkg.in/natefinch/lumberjack.v2/README.md @@ -0,0 +1,174 @@ +# lumberjack [](https://godoc.org/gopkg.in/natefinch/lumberjack.v2) [](https://drone.io/github.com/natefinch/lumberjack/latest) [](https://ci.appveyor.com/project/natefinch/lumberjack) [](https://coveralls.io/r/natefinch/lumberjack?branch=v2.0) + +### Lumberjack is a Go package for writing logs to rolling files. + +Package lumberjack provides a rolling logger. + +Note that this is v2.0 of lumberjack, and should be imported using gopkg.in +thusly: + + import "gopkg.in/natefinch/lumberjack.v2" + +The package name remains simply lumberjack, and the code resides at +https://github.com/natefinch/lumberjack under the v2.0 branch. + +Lumberjack is intended to be one part of a logging infrastructure. +It is not an all-in-one solution, but instead is a pluggable +component at the bottom of the logging stack that simply controls the files +to which logs are written. + +Lumberjack plays well with any logging package that can write to an +io.Writer, including the standard library's log package. + +Lumberjack assumes that only one process is writing to the output files. +Using the same lumberjack configuration from multiple processes on the same +machine will result in improper behavior. + + +**Example** + +To use lumberjack with the standard library's log package, just pass it into the SetOutput function when your application starts. + +Code: + +```go +log.SetOutput(&lumberjack.Logger{ + Filename: "/var/log/myapp/foo.log", + MaxSize: 500, // megabytes + MaxBackups: 3, + MaxAge: 28, //days +}) +``` + + + +## type Logger +``` go +type Logger struct { + // Filename is the file to write logs to. Backup log files will be retained + // in the same directory. It uses <processname>-lumberjack.log in + // os.TempDir() if empty. + Filename string `json:"filename" yaml:"filename"` + + // MaxSize is the maximum size in megabytes of the log file before it gets + // rotated. It defaults to 100 megabytes. + MaxSize int `json:"maxsize" yaml:"maxsize"` + + // MaxAge is the maximum number of days to retain old log files based on the + // timestamp encoded in their filename. Note that a day is defined as 24 + // hours and may not exactly correspond to calendar days due to daylight + // savings, leap seconds, etc. The default is not to remove old log files + // based on age. + MaxAge int `json:"maxage" yaml:"maxage"` + + // MaxBackups is the maximum number of old log files to retain. The default + // is to retain all old log files (though MaxAge may still cause them to get + // deleted.) + MaxBackups int `json:"maxbackups" yaml:"maxbackups"` + + // LocalTime determines if the time used for formatting the timestamps in + // backup files is the computer's local time. The default is to use UTC + // time. + LocalTime bool `json:"localtime" yaml:"localtime"` + // contains filtered or unexported fields +} +``` +Logger is an io.WriteCloser that writes to the specified filename. + +Logger opens or creates the logfile on first Write. If the file exists and +is less than MaxSize megabytes, lumberjack will open and append to that file. +If the file exists and its size is >= MaxSize megabytes, the file is renamed +by putting the current time in a timestamp in the name immediately before the +file's extension (or the end of the filename if there's no extension). A new +log file is then created using original filename. + +Whenever a write would cause the current log file exceed MaxSize megabytes, +the current file is closed, renamed, and a new log file created with the +original name. Thus, the filename you give Logger is always the "current" log +file. + +Backups use the log file name given to Logger, in the form `name-timestamp.ext` +where name is the filename without the extension, timestamp is the time at which +the log was rotated formatted with the time.Time format of +`2006-01-02T15-04-05.000` and the extension is the original extension. For +example, if your Logger.Filename is `/var/log/foo/server.log`, a backup created +at 6:30pm on Nov 11 2016 would use the filename +`/var/log/foo/server-2016-11-04T18-30-00.000.log` + +### Cleaning Up Old Log Files +Whenever a new logfile gets created, old log files may be deleted. The most +recent files according to the encoded timestamp will be retained, up to a +number equal to MaxBackups (or all of them if MaxBackups is 0). Any files +with an encoded timestamp older than MaxAge days are deleted, regardless of +MaxBackups. Note that the time encoded in the timestamp is the rotation +time, which may differ from the last time that file was written to. + +If MaxBackups and MaxAge are both 0, no old log files will be deleted. + + + + + + + + + + + +### func (\*Logger) Close +``` go +func (l *Logger) Close() error +``` +Close implements io.Closer, and closes the current logfile. + + + +### func (\*Logger) Rotate +``` go +func (l *Logger) Rotate() error +``` +Rotate causes Logger to close the existing log file and immediately create a +new one. This is a helper function for applications that want to initiate +rotations outside of the normal rotation rules, such as in response to +SIGHUP. After rotating, this initiates a cleanup of old log files according +to the normal rules. + +**Example** + +Example of how to rotate in response to SIGHUP. + +Code: + +```go +l := &lumberjack.Logger{} +log.SetOutput(l) +c := make(chan os.Signal, 1) +signal.Notify(c, syscall.SIGHUP) + +go func() { + for { + <-c + l.Rotate() + } +}() +``` + +### func (\*Logger) Write +``` go +func (l *Logger) Write(p []byte) (n int, err error) +``` +Write implements io.Writer. If a write would cause the log file to be larger +than MaxSize, the file is closed, renamed to include a timestamp of the +current time, and a new log file is created using the original log file name. +If the length of the write is greater than MaxSize, an error is returned. + + + + + + + + + +- - - +Generated by [godoc2md](http://godoc.org/github.com/davecheney/godoc2md) |