// handleLog consumes and logs any Entry's passed to the channel
func (s *Syslog) handleLog(entries <-chan *log.Entry) {
var e *log.Entry
var line string
formatter := s.formatFunc(s)
for e = range entries {
line = string(formatter(e))
switch e.Level {
case log.DebugLevel:
s.writer.Debug(line)
case log.TraceLevel, log.InfoLevel:
s.writer.Info(line)
case log.NoticeLevel:
s.writer.Notice(line)
case log.WarnLevel:
s.writer.Warning(line)
case log.ErrorLevel:
s.writer.Err(line)
case log.PanicLevel, log.AlertLevel:
s.writer.Alert(line)
case log.FatalLevel:
s.writer.Crit(line)
}
e.Consumed()
}
}
// HandleLog is the default http log handler
func HandleLog(h HTTP, entries <-chan *log.Entry) {
var e *log.Entry
var b []byte
var reader *bytes.Reader
formatter := h.FormatFunc()(h)
remoteHost := h.RemoteHost()
httpClient := stdhttp.Client{}
req, _ := stdhttp.NewRequest(h.Method(), remoteHost, nil)
req.Header = h.Headers()
for e = range entries {
b = formatter(e)
reader = bytes.NewReader(b)
req.Body = ioutil.NopCloser(reader)
req.ContentLength = int64(reader.Len())
resp, err := httpClient.Do(req)
if err != nil {
log.Error("Could not post data to %s: %v\n", remoteHost, err)
goto END
}
if resp.StatusCode < 200 || resp.StatusCode >= 299 {
bt, _ := ioutil.ReadAll(resp.Body)
log.Error("Received HTTP %d during POST request to %s body: %s\n", resp.StatusCode, remoteHost, string(bt))
}
END:
e.Consumed()
}
}
// handleLog consumes and logs any Entry's passed to the channel
func (c *Console) handleLog(entries <-chan *log.Entry) {
var e *log.Entry
// var b io.WriterTo
var b []byte
formatter := c.formatFunc(c)
for e = range entries {
b = formatter(e)
c.writer.Write(b)
e.Consumed()
}
}
// Run starts the logger consuming on the returned channed
func (c *CustomHandler) Run() chan<- *log.Entry {
// in a big high traffic app, set a higher buffer
ch := make(chan *log.Entry, c.buffer)
// can run as many consumers on the channel as you want,
// depending on the buffer size or your needs
go func(entries <-chan *log.Entry) {
// below prints to os.Stderr but could marshal to JSON
// and send to central logging server
// ---------
// |----------> | console |
// | ---------
// i.e. ----------------- ----------------- Unmarshal ------------- --------
// | app log handler | -- json --> | central log app | -- to -> | log handler | --> | syslog |
// ----------------- ----------------- Entry ------------- --------
// | ---------
// |----------> | DataDog |
// ---------
var e *log.Entry
b := new(bytes.Buffer)
for e = range entries {
b.Reset()
b.WriteString(e.Message)
for _, f := range e.Fields {
fmt.Fprintf(b, " %s=%v", f.Key, f.Value)
}
fmt.Println(b.String())
e.Consumed() // done writing the entry
}
}(ch)
return ch
}
func (email *Email) handleLog(entries <-chan *log.Entry) {
var e *log.Entry
var s gomail.SendCloser
var err error
var open bool
var alreadyTriedSending bool
var message *gomail.Message
var count uint8
formatter := email.formatFunc(email)
d := gomail.NewDialer(email.host, email.port, email.username, email.password)
for {
select {
case e = <-entries:
count = 0
alreadyTriedSending = false
message = formatter(e)
REOPEN:
// check if smtp connection open
if !open {
count++
if s, err = d.Dial(); err != nil {
log.WithFields(log.F("error", err)).Warn("ERROR connection to smtp server")
if count == 3 {
// we tried to reconnect...
e.Consumed()
break
}
goto REOPEN
}
count = 0
open = true
}
RESEND:
count++
if err = gomail.Send(s, message); err != nil {
log.WithFields(log.F("error", err)).Warn("ERROR sending to smtp server, retrying")
if count == 3 && !alreadyTriedSending {
// maybe we got disconnected...
alreadyTriedSending = true
open = false
s.Close()
goto REOPEN
} else if alreadyTriedSending {
// we reopened and tried 2 more times, can;t say we didn't try
log.WithFields(log.F("error", err)).Alert("ERROR sending log via EMAIL, RETRY and REOPEN failed")
e.Consumed()
break
}
goto RESEND
}
e.Consumed()
case <-time.After(email.keepalive):
if open {
s.Close()
open = false
}
}
}
}
