in logging_handler.go [120:160]
func (h loggingHandler) writeLogLine(username, upstream string, req *http.Request, url url.URL, ts time.Time, status int, size int) {
if username == "" {
username = "-"
}
if upstream == "" {
upstream = "-"
}
if url.User != nil && username == "-" {
if name := url.User.Username(); name != "" {
username = name
}
}
client := req.Header.Get("X-Real-IP")
if client == "" {
client = req.RemoteAddr
}
if c, _, err := net.SplitHostPort(client); err == nil {
client = c
}
duration := float64(time.Now().Sub(ts)) / float64(time.Second)
h.logTemplate.Execute(h.writer, logMessageData{
Client: client,
Host: req.Host,
Protocol: req.Proto,
RequestDuration: fmt.Sprintf("%0.3f", duration),
RequestMethod: req.Method,
RequestURI: fmt.Sprintf("%q", url.RequestURI()),
ResponseSize: fmt.Sprintf("%d", size),
StatusCode: fmt.Sprintf("%d", status),
Timestamp: ts.Format("02/Jan/2006:15:04:05 -0700"),
Upstream: upstream,
UserAgent: fmt.Sprintf("%q", req.UserAgent()),
Username: username,
})
h.writer.Write([]byte("\n"))
}