services/keepstore/logging_router.go

   1 package main
   2
   3 // LoggingRESTRouter
   4 // LoggingResponseWriter
   5
   6 import (
   7         "log"
   8         "net/http"
   9         "strings"
  10         "time"
  11 )
  12
  13 // LoggingResponseWriter has anonymous fields ResponseWriter and ResponseBody
  14 type LoggingResponseWriter struct {
  15         Status int
  16         Length int
  17         http.ResponseWriter
  18         ResponseBody string
  19         sentHdr      time.Time
  20 }
  21
  22 // WriteHeader writes header to ResponseWriter
  23 func (loggingWriter *LoggingResponseWriter) WriteHeader(code int) {
  24         if loggingWriter.sentHdr == zeroTime {
  25                 loggingWriter.sentHdr = time.Now()
  26         }
  27         loggingWriter.Status = code
  28         loggingWriter.ResponseWriter.WriteHeader(code)
  29 }
  30
  31 var zeroTime time.Time
  32
  33 func (loggingWriter *LoggingResponseWriter) Write(data []byte) (int, error) {
  34         if loggingWriter.Length == 0 && len(data) > 0 && loggingWriter.sentHdr == zeroTime {
  35                 loggingWriter.sentHdr = time.Now()
  36         }
  37         loggingWriter.Length += len(data)
  38         if loggingWriter.Status >= 400 {
  39                 loggingWriter.ResponseBody += string(data)
  40         }
  41         return loggingWriter.ResponseWriter.Write(data)
  42 }
  43
  44 // LoggingRESTRouter is used to add logging capabilities to mux.Router
  45 type LoggingRESTRouter struct {
  46         router http.Handler
  47 }
  48
  49 func (loggingRouter *LoggingRESTRouter) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
  50         t0 := time.Now()
  51         loggingWriter := LoggingResponseWriter{http.StatusOK, 0, resp, "", zeroTime}
  52         loggingRouter.router.ServeHTTP(&loggingWriter, req)
  53         statusText := http.StatusText(loggingWriter.Status)
  54         if loggingWriter.Status >= 400 {
  55                 statusText = strings.Replace(loggingWriter.ResponseBody, "\n", "", -1)
  56         }
  57         now := time.Now()
  58         tTotal := now.Sub(t0)
  59         tLatency := loggingWriter.sentHdr.Sub(t0)
  60         tResponse := now.Sub(loggingWriter.sentHdr)
  61         log.Printf("[%s] %s %s %d %.6fs %.6fs %.6fs %d %d \"%s\"", req.RemoteAddr, req.Method, req.URL.Path[1:], req.ContentLength, tTotal.Seconds(), tLatency.Seconds(), tResponse.Seconds(), loggingWriter.Status, loggingWriter.Length, statusText)
  62
  63 }