syncthing/vendor/github.com/sirupsen/logrus/logrus.go
Jakob Borg 916ec63af6 cmd/stdiscosrv: New discovery server (fixes #4618)
This is a new revision of the discovery server. Relevant changes and
non-changes:

- Protocol towards clients is unchanged.

- Recommended large scale design is still to be deployed nehind nginx (I
  tested, and it's still a lot faster at terminating TLS).

- Database backend is leveldb again, only. It scales enough, is easy to
  setup, and we don't need any backend to take care of.

- Server supports replication. This is a simple TCP channel - protect it
  with a firewall when deploying over the internet. (We deploy this within
  the same datacenter, and with firewall.) Any incoming client announces
  are sent over the replication channel(s) to other peer discosrvs.
  Incoming replication changes are applied to the database as if they came
  from clients, but without the TLS/certificate overhead.

- Metrics are exposed using the prometheus library, when enabled.

- The database values and replication protocol is protobuf, because JSON
  was quite CPU intensive when I tried that and benchmarked it.

- The "Retry-After" value for failed lookups gets slowly increased from
  a default of 120 seconds, by 5 seconds for each failed lookup,
  independently by each discosrv. This lowers the query load over time for
  clients that are never seen. The Retry-After maxes out at 3600 after a
  couple of weeks of this increase. The number of failed lookups is
  stored in the database, now and then (avoiding making each lookup a
  database put).

All in all this means clients can be pointed towards a cluster using
just multiple A / AAAA records to gain both load sharing and redundancy
(if one is down, clients will talk to the remaining ones).

GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4648
2018-01-14 08:52:31 +00:00

144 lines
3.6 KiB
Go

package logrus
import (
"fmt"
"log"
"strings"
)
// Fields type, used to pass to `WithFields`.
type Fields map[string]interface{}
// Level type
type Level uint32
// Convert the Level to a string. E.g. PanicLevel becomes "panic".
func (level Level) String() string {
switch level {
case DebugLevel:
return "debug"
case InfoLevel:
return "info"
case WarnLevel:
return "warning"
case ErrorLevel:
return "error"
case FatalLevel:
return "fatal"
case PanicLevel:
return "panic"
}
return "unknown"
}
// ParseLevel takes a string level and returns the Logrus log level constant.
func ParseLevel(lvl string) (Level, error) {
switch strings.ToLower(lvl) {
case "panic":
return PanicLevel, nil
case "fatal":
return FatalLevel, nil
case "error":
return ErrorLevel, nil
case "warn", "warning":
return WarnLevel, nil
case "info":
return InfoLevel, nil
case "debug":
return DebugLevel, nil
}
var l Level
return l, fmt.Errorf("not a valid logrus Level: %q", lvl)
}
// A constant exposing all logging levels
var AllLevels = []Level{
PanicLevel,
FatalLevel,
ErrorLevel,
WarnLevel,
InfoLevel,
DebugLevel,
}
// These are the different logging levels. You can set the logging level to log
// on your instance of logger, obtained with `logrus.New()`.
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
)
// Won't compile if StdLogger can't be realized by a log.Logger
var (
_ StdLogger = &log.Logger{}
_ StdLogger = &Entry{}
_ StdLogger = &Logger{}
)
// 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 StdLogger interface {
Print(...interface{})
Printf(string, ...interface{})
Println(...interface{})
Fatal(...interface{})
Fatalf(string, ...interface{})
Fatalln(...interface{})
Panic(...interface{})
Panicf(string, ...interface{})
Panicln(...interface{})
}
// The FieldLogger interface generalizes the Entry and Logger types
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{})
}