package middlewares import ( "bufio" "fmt" "io" "net" "net/http" "os" "strconv" "strings" "sync/atomic" "time" log "github.com/Sirupsen/logrus" "github.com/streamrail/concurrent-map" ) const ( loggerReqidHeader = "X-Traefik-Reqid" ) /* Logger writes each request and its response to the access log. It gets some information from the logInfoResponseWriter set up by previous middleware. */ type Logger struct { file *os.File } // Logging handler to log frontend name, backend name, and elapsed time type frontendBackendLoggingHandler struct { reqid string writer io.Writer handlerFunc http.HandlerFunc } var ( reqidCounter uint64 // Request ID infoRwMap = cmap.New() // Map of reqid to response writer backend2FrontendMap *map[string]string ) // logInfoResponseWriter is a wrapper of type http.ResponseWriter // that tracks frontend and backend names and request status and size type logInfoResponseWriter struct { rw http.ResponseWriter backend string frontend string status int size int } // NewLogger returns a new Logger instance. func NewLogger(file string) *Logger { if len(file) > 0 { fi, err := os.OpenFile(file, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666) if err != nil { log.Error("Error opening file", err) } return &Logger{fi} } return &Logger{nil} } // SetBackend2FrontendMap is called by server.go to set up frontend translation func SetBackend2FrontendMap(newMap *map[string]string) { backend2FrontendMap = newMap } func (l *Logger) ServeHTTP(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) { if l.file == nil { next(rw, r) } else { reqid := strconv.FormatUint(atomic.AddUint64(&reqidCounter, 1), 10) r.Header[loggerReqidHeader] = []string{reqid} defer deleteReqid(r, reqid) frontendBackendLoggingHandler{reqid, l.file, next}.ServeHTTP(rw, r) } } // Delete a reqid from the map and the request's headers func deleteReqid(r *http.Request, reqid string) { infoRwMap.Remove(reqid) delete(r.Header, loggerReqidHeader) } // Save the backend name for the Logger func saveBackendNameForLogger(r *http.Request, backendName string) { if reqidHdr := r.Header[loggerReqidHeader]; len(reqidHdr) == 1 { reqid := reqidHdr[0] if infoRw, ok := infoRwMap.Get(reqid); ok { infoRw.(*logInfoResponseWriter).SetBackend(backendName) infoRw.(*logInfoResponseWriter).SetFrontend((*backend2FrontendMap)[backendName]) } } } // Close closes the Logger (i.e. the file). func (l *Logger) Close() { if l.file != nil { l.file.Close() } } // Logging handler to log frontend name, backend name, and elapsed time func (fblh frontendBackendLoggingHandler) ServeHTTP(rw http.ResponseWriter, req *http.Request) { startTime := time.Now() infoRw := &logInfoResponseWriter{rw: rw} infoRwMap.Set(fblh.reqid, infoRw) fblh.handlerFunc(infoRw, req) username := "-" url := *req.URL if url.User != nil { if name := url.User.Username(); name != "" { username = name } } host, _, err := net.SplitHostPort(req.RemoteAddr) if err != nil { host = req.RemoteAddr } ts := startTime.Format("02/Jan/2006:15:04:05 -0700") method := req.Method uri := url.RequestURI() if qmIndex := strings.Index(uri, "?"); qmIndex > 0 { uri = uri[0:qmIndex] } proto := req.Proto referer := req.Referer() agent := req.UserAgent() frontend := strings.TrimPrefix(infoRw.GetFrontend(), "frontend-") backend := infoRw.GetBackend() status := infoRw.GetStatus() size := infoRw.GetSize() elapsed := time.Now().UTC().Sub(startTime.UTC()) elapsedMillis := elapsed.Nanoseconds() / 1000000 fmt.Fprintf(fblh.writer, `%s - %s [%s] "%s %s %s" %d %d "%s" "%s" %s "%s" "%s" %dms%s`, host, username, ts, method, uri, proto, status, size, referer, agent, fblh.reqid, frontend, backend, elapsedMillis, "\n") } func (lirw *logInfoResponseWriter) Header() http.Header { return lirw.rw.Header() } func (lirw *logInfoResponseWriter) Write(b []byte) (int, error) { if lirw.status == 0 { lirw.status = http.StatusOK } size, err := lirw.rw.Write(b) lirw.size += size return size, err } func (lirw *logInfoResponseWriter) WriteHeader(s int) { lirw.rw.WriteHeader(s) lirw.status = s } func (lirw *logInfoResponseWriter) Flush() { f, ok := lirw.rw.(http.Flusher) if ok { f.Flush() } } func (lirw *logInfoResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) { return lirw.rw.(http.Hijacker).Hijack() } func (lirw *logInfoResponseWriter) GetStatus() int { return lirw.status } func (lirw *logInfoResponseWriter) GetSize() int { return lirw.size } func (lirw *logInfoResponseWriter) GetBackend() string { return lirw.backend } func (lirw *logInfoResponseWriter) GetFrontend() string { return lirw.frontend } func (lirw *logInfoResponseWriter) SetBackend(backend string) { lirw.backend = backend } func (lirw *logInfoResponseWriter) SetFrontend(frontend string) { lirw.frontend = frontend }