const DefaultTimestampFormat = time.RFC3339
var AllLevels = []Level{ PanicLevel, FatalLevel, ErrorLevel, WarnLevel, InfoLevel, DebugLevel, }
A constant exposing all logging levels
var ErrorKey = "error"
Defines the key when adding errors using WithError.
func AddHook(hook Hook)
AddHook adds a hook to the standard logger hooks.
func Debug(args ...interface{})
Debug logs a message at level Debug on the standard logger.
func Debugf(format string, args ...interface{})
Debugf logs a message at level Debug on the standard logger.
func Debugln(args ...interface{})
Debugln logs a message at level Debug on the standard logger.
func Error(args ...interface{})
Error logs a message at level Error on the standard logger.
func Errorf(format string, args ...interface{})
Errorf logs a message at level Error on the standard logger.
func Errorln(args ...interface{})
Errorln logs a message at level Error on the standard logger.
func Exit(code int)
Exit runs all the Logrus atexit handlers and then terminates the program using os.Exit(code)
func Fatal(args ...interface{})
Fatal logs a message at level Fatal on the standard logger.
func Fatalf(format string, args ...interface{})
Fatalf logs a message at level Fatal on the standard logger.
func Fatalln(args ...interface{})
Fatalln logs a message at level Fatal on the standard logger.
func Info(args ...interface{})
Info logs a message at level Info on the standard logger.
func Infof(format string, args ...interface{})
Infof logs a message at level Info on the standard logger.
func Infoln(args ...interface{})
Infoln logs a message at level Info on the standard logger.
func IsTerminal() bool
IsTerminal returns true if stderr's file descriptor is a terminal.
func Panic(args ...interface{})
Panic logs a message at level Panic on the standard logger.
func Panicf(format string, args ...interface{})
Panicf logs a message at level Panic on the standard logger.
func Panicln(args ...interface{})
Panicln logs a message at level Panic on the standard logger.
func Print(args ...interface{})
Print logs a message at level Info on the standard logger.
func Printf(format string, args ...interface{})
Printf logs a message at level Info on the standard logger.
func Println(args ...interface{})
Println logs a message at level Info on the standard logger.
func RegisterExitHandler(handler func())
RegisterExitHandler adds a Logrus Exit handler, call logrus.Exit to invoke all handlers. The handlers will also be invoked when any Fatal log entry is made.
This method is useful when a caller wishes to use logrus to log a fatal message but also needs to gracefully shutdown. An example usecase could be closing database connections, or sending a alert that the application is closing.
func SetFormatter(formatter Formatter)
SetFormatter sets the standard logger formatter.
func SetLevel(level Level)
SetLevel sets the standard logger level.
func SetOutput(out io.Writer)
SetOutput sets the standard logger output.
func Warn(args ...interface{})
Warn logs a message at level Warn on the standard logger.
func Warnf(format string, args ...interface{})
Warnf logs a message at level Warn on the standard logger.
func Warning(args ...interface{})
Warning logs a message at level Warn on the standard logger.
func Warningf(format string, args ...interface{})
Warningf logs a message at level Warn on the standard logger.
func Warningln(args ...interface{})
Warningln logs a message at level Warn on the standard logger.
func Warnln(args ...interface{})
Warnln logs a message at level Warn on the standard logger.
type Entry struct {
Logger *Logger
// Contains all the fields set by the user.
Data Fields
// Time at which the log entry was created
Time time.Time
// Level the log entry was logged at: Debug, Info, Warn, Error, Fatal or Panic
Level Level
// Message passed to Debug, Info, Warn, Error, Fatal or Panic
Message string
}
An entry is the final or intermediate Logrus logging entry. It contains all the fields passed with WithField{,s}. It's finally logged when Debug, Info, Warn, Error, Fatal or Panic is called on it. These objects can be reused and passed around as much as you wish to avoid field duplication.
func NewEntry(logger *Logger) *Entry
func WithError(err error) *Entry
WithError creates an entry from the standard logger and adds an error to it, using the value defined in ErrorKey as key.
func WithField(key string, value interface{}) *Entry
WithField creates an entry from the standard logger and adds a field to it. If you want multiple fields, use `WithFields`.
Note that it doesn't log until you call Debug, Print, Info, Warn, Fatal or Panic on the Entry it returns.
func WithFields(fields Fields) *Entry
WithFields creates an entry from the standard logger and adds multiple fields to it. This is simply a helper for `WithField`, invoking it once for each field.
Note that it doesn't log until you call Debug, Print, Info, Warn, Fatal or Panic on the Entry it returns.
func (entry *Entry) Debug(args ...interface{})
func (entry *Entry) Debugf(format string, args ...interface{})
func (entry *Entry) Debugln(args ...interface{})
func (entry *Entry) Error(args ...interface{})
func (entry *Entry) Errorf(format string, args ...interface{})
func (entry *Entry) Errorln(args ...interface{})
func (entry *Entry) Fatal(args ...interface{})
func (entry *Entry) Fatalf(format string, args ...interface{})
func (entry *Entry) Fatalln(args ...interface{})
func (entry *Entry) Info(args ...interface{})
func (entry *Entry) Infof(format string, args ...interface{})
func (entry *Entry) Infoln(args ...interface{})
func (entry *Entry) Panic(args ...interface{})
func (entry *Entry) Panicf(format string, args ...interface{})
func (entry *Entry) Panicln(args ...interface{})
func (entry *Entry) Print(args ...interface{})
func (entry *Entry) Printf(format string, args ...interface{})
func (entry *Entry) Println(args ...interface{})
func (entry *Entry) Reader() (*bytes.Buffer, error)
Returns a reader for the entry, which is a proxy to the formatter.
func (entry *Entry) String() (string, error)
Returns the string representation from the reader and ultimately the formatter.
func (entry *Entry) Warn(args ...interface{})
func (entry *Entry) Warnf(format string, args ...interface{})
func (entry *Entry) Warning(args ...interface{})
func (entry *Entry) Warningf(format string, args ...interface{})
func (entry *Entry) Warningln(args ...interface{})
func (entry *Entry) Warnln(args ...interface{})
func (entry *Entry) WithError(err error) *Entry
Add an error as single field (using the key defined in ErrorKey) to the Entry.
func (entry *Entry) WithField(key string, value interface{}) *Entry
Add a single field to the Entry.
func (entry *Entry) WithFields(fields Fields) *Entry
Add a map of fields to the Entry.
type FieldLogger interface {
WithField(key string, value interface{}) *Entry
WithFields(fields Fields) *Entry
WithError(err error) *Entry
Debugf(format string, args ...interface{})
Infof(format string, args ...interface{})
Printf(format string, args ...interface{})
Warnf(format string, args ...interface{})
Warningf(format string, args ...interface{})
Errorf(format string, args ...interface{})
Fatalf(format string, args ...interface{})
Panicf(format string, args ...interface{})
Debug(args ...interface{})
Info(args ...interface{})
Print(args ...interface{})
Warn(args ...interface{})
Warning(args ...interface{})
Error(args ...interface{})
Fatal(args ...interface{})
Panic(args ...interface{})
Debugln(args ...interface{})
Infoln(args ...interface{})
Println(args ...interface{})
Warnln(args ...interface{})
Warningln(args ...interface{})
Errorln(args ...interface{})
Fatalln(args ...interface{})
Panicln(args ...interface{})
}
The FieldLogger interface generalizes the Entry and Logger types
type Fields map[string]interface{}
Fields type, used to pass to `WithFields`.
type Formatter interface {
Format(*Entry) ([]byte, error)
}
The Formatter interface is used to implement a custom Formatter. It takes an `Entry`. It exposes all the fields, including the default ones:
* `entry.Data["msg"]`. The message passed from Info, Warn, Error .. * `entry.Data["time"]`. The timestamp. * `entry.Data["level"]. The level the entry was logged at.
Any additional fields added with `WithField` or `WithFields` are also in `entry.Data`. Format is expected to return an array of bytes which are then logged to `logger.Out`.
type Hook interface {
Levels() []Level
Fire(*Entry) error
}
A hook to be fired when logging on the logging levels returned from `Levels()` on your implementation of the interface. Note that this is not fired in a goroutine or a channel with workers, you should handle such functionality yourself if your call is non-blocking and you don't wish for the logging calls for levels returned from `Levels()` to block.
type JSONFormatter struct {
// TimestampFormat sets the format used for marshaling timestamps.
TimestampFormat string
}
func (f *JSONFormatter) Format(entry *Entry) ([]byte, error)
type Level uint8
Level type
const (
// PanicLevel level, highest level of severity. Logs and then calls panic with the
// message passed to Debug, Info, ...
PanicLevel Level = iota
// FatalLevel level. Logs and then calls `os.Exit(1)`. It will exit even if the
// logging level is set to Panic.
FatalLevel
// ErrorLevel level. Logs. Used for errors that should definitely be noted.
// Commonly used for hooks to send errors to an error tracking service.
ErrorLevel
// WarnLevel level. Non-critical entries that deserve eyes.
WarnLevel
// InfoLevel level. General operational entries about what's going on inside the
// application.
InfoLevel
// DebugLevel level. Usually only enabled when debugging. Very verbose logging.
DebugLevel
)
These are the different logging levels. You can set the logging level to log on your instance of logger, obtained with `logrus.New()`.
func GetLevel() Level
GetLevel returns the standard logger level.
func ParseLevel(lvl string) (Level, error)
ParseLevel takes a string level and returns the Logrus log level constant.
func (level Level) String() string
Convert the Level to a string. E.g. PanicLevel becomes "panic".
type LevelHooks map[Level][]Hook
Internal type for storing the hooks on a logger instance.
func (hooks LevelHooks) Add(hook Hook)
Add a hook to an instance of logger. This is called with `log.Hooks.Add(new(MyHook))` where `MyHook` implements the `Hook` interface.
func (hooks LevelHooks) Fire(level Level, entry *Entry) error
Fire all the hooks for the passed level. Used by `entry.log` to fire appropriate hooks for a log entry.
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 adventorous, 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
// 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. `logrus.Debug` is useful in
Level Level
// contains filtered or unexported fields
}
func New() *Logger
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 = &Logger{
Out: os.Stderr,
Formatter: new(JSONFormatter),
Hooks: make(LevelHooks),
Level: logrus.DebugLevel,
}
It's recommended to make this a global instance called `log`.
func StandardLogger() *Logger
func (logger *Logger) Debug(args ...interface{})
func (logger *Logger) Debugf(format string, args ...interface{})
func (logger *Logger) Debugln(args ...interface{})
func (logger *Logger) Error(args ...interface{})
func (logger *Logger) Errorf(format string, args ...interface{})
func (logger *Logger) Errorln(args ...interface{})
func (logger *Logger) Fatal(args ...interface{})
func (logger *Logger) Fatalf(format string, args ...interface{})
func (logger *Logger) Fatalln(args ...interface{})
func (logger *Logger) Info(args ...interface{})
func (logger *Logger) Infof(format string, args ...interface{})
func (logger *Logger) Infoln(args ...interface{})
func (logger *Logger) Panic(args ...interface{})
func (logger *Logger) Panicf(format string, args ...interface{})
func (logger *Logger) Panicln(args ...interface{})
func (logger *Logger) Print(args ...interface{})
func (logger *Logger) Printf(format string, args ...interface{})
func (logger *Logger) Println(args ...interface{})
func (logger *Logger) Warn(args ...interface{})
func (logger *Logger) Warnf(format string, args ...interface{})
func (logger *Logger) Warning(args ...interface{})
func (logger *Logger) Warningf(format string, args ...interface{})
func (logger *Logger) Warningln(args ...interface{})
func (logger *Logger) Warnln(args ...interface{})
func (logger *Logger) WithError(err error) *Entry
Add an error as single field to the log entry. All it does is call `WithError` for the given `error`.
func (logger *Logger) WithField(key string, value interface{}) *Entry
Adds a field to the log entry, note that it doesn't log until you call Debug, Print, Info, Warn, Fatal or Panic. It only creates a log entry. If you want multiple fields, use `WithFields`.
func (logger *Logger) WithFields(fields Fields) *Entry
Adds a struct of fields to the log entry. All it does is call `WithField` for each `Field`.
func (logger *Logger) Writer() *io.PipeWriter
func (logger *Logger) WriterLevel(level Level) *io.PipeWriter
type StdLogger interface {
Print(...interface{})
Printf(string, ...interface{})
Println(...interface{})
Fatal(...interface{})
Fatalf(string, ...interface{})
Fatalln(...interface{})
Panic(...interface{})
Panicf(string, ...interface{})
Panicln(...interface{})
}
StdLogger is what your logrus-enabled library should take, that way it'll accept a stdlib logger and a logrus logger. There's no standard interface, this is the closest we get, unfortunately.
type Termios syscall.Termios
type TextFormatter struct {
// Set to true to bypass checking for a TTY before outputting colors.
ForceColors bool
// Force disabling colors.
DisableColors bool
// Disable timestamp logging. useful when output is redirected to logging
// system that already adds timestamps.
DisableTimestamp bool
// Enable logging the full timestamp when a TTY is attached instead of just
// the time passed since beginning of execution.
FullTimestamp bool
// TimestampFormat to use for display when a full timestamp is printed
TimestampFormat string
// The fields are sorted by default for a consistent output. For applications
// that log extremely frequently and don't use the JSON formatter this may not
// be desired.
DisableSorting bool
}
func (f *TextFormatter) Format(entry *Entry) ([]byte, error)