| // Copyright 2015 The Prometheus Authors |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // +build !windows,!nacl,!plan9 |
| |
| package log |
| |
| import ( |
| "fmt" |
| "log/syslog" |
| "os" |
| |
| "github.com/sirupsen/logrus" |
| ) |
| |
| var _ logrus.Formatter = (*syslogger)(nil) |
| |
| func init() { |
| setSyslogFormatter = func(l logger, appname, local string) error { |
| if appname == "" { |
| return fmt.Errorf("missing appname parameter") |
| } |
| if local == "" { |
| return fmt.Errorf("missing local parameter") |
| } |
| |
| fmter, err := newSyslogger(appname, local, l.entry.Logger.Formatter) |
| if err != nil { |
| fmt.Fprintf(os.Stderr, "error creating syslog formatter: %v\n", err) |
| l.entry.Errorf("can't connect logger to syslog: %v", err) |
| return err |
| } |
| l.entry.Logger.Formatter = fmter |
| return nil |
| } |
| } |
| |
| var prefixTag []byte |
| |
| type syslogger struct { |
| wrap logrus.Formatter |
| out *syslog.Writer |
| } |
| |
| func newSyslogger(appname string, facility string, fmter logrus.Formatter) (*syslogger, error) { |
| priority, err := getFacility(facility) |
| if err != nil { |
| return nil, err |
| } |
| out, err := syslog.New(priority, appname) |
| _, isJSON := fmter.(*logrus.JSONFormatter) |
| if isJSON { |
| // add cee tag to json formatted syslogs |
| prefixTag = []byte("@cee:") |
| } |
| return &syslogger{ |
| out: out, |
| wrap: fmter, |
| }, err |
| } |
| |
| func getFacility(facility string) (syslog.Priority, error) { |
| switch facility { |
| case "0": |
| return syslog.LOG_LOCAL0, nil |
| case "1": |
| return syslog.LOG_LOCAL1, nil |
| case "2": |
| return syslog.LOG_LOCAL2, nil |
| case "3": |
| return syslog.LOG_LOCAL3, nil |
| case "4": |
| return syslog.LOG_LOCAL4, nil |
| case "5": |
| return syslog.LOG_LOCAL5, nil |
| case "6": |
| return syslog.LOG_LOCAL6, nil |
| case "7": |
| return syslog.LOG_LOCAL7, nil |
| } |
| return syslog.LOG_LOCAL0, fmt.Errorf("invalid local(%s) for syslog", facility) |
| } |
| |
| func (s *syslogger) Format(e *logrus.Entry) ([]byte, error) { |
| data, err := s.wrap.Format(e) |
| if err != nil { |
| fmt.Fprintf(os.Stderr, "syslogger: can't format entry: %v\n", err) |
| return data, err |
| } |
| // only append tag to data sent to syslog (line), not to what |
| // is returned |
| line := string(append(prefixTag, data...)) |
| |
| switch e.Level { |
| case logrus.PanicLevel: |
| err = s.out.Crit(line) |
| case logrus.FatalLevel: |
| err = s.out.Crit(line) |
| case logrus.ErrorLevel: |
| err = s.out.Err(line) |
| case logrus.WarnLevel: |
| err = s.out.Warning(line) |
| case logrus.InfoLevel: |
| err = s.out.Info(line) |
| case logrus.DebugLevel: |
| err = s.out.Debug(line) |
| default: |
| err = s.out.Notice(line) |
| } |
| |
| if err != nil { |
| fmt.Fprintf(os.Stderr, "syslogger: can't send log to syslog: %v\n", err) |
| } |
| |
| return data, err |
| } |