package web import ( "bufio" "errors" "fmt" "net" "net/http" "time" log "github.com/sirupsen/logrus" ) // responseLogger is wrapper of http.ResponseWriter that keeps track of its HTTP status // code and body size type responseLogger struct { w http.ResponseWriter status int size int upstream string } // Header returns the ResponseWriter's Header func (l *responseLogger) Header() http.Header { return l.w.Header() } // Support Websocket func (l *responseLogger) Hijack() (rwc net.Conn, buf *bufio.ReadWriter, err error) { if hj, ok := l.w.(http.Hijacker); ok { return hj.Hijack() } return nil, nil, errors.New("http.Hijacker is not available on writer") } // Write writes the response using the ResponseWriter func (l *responseLogger) Write(b []byte) (int, error) { if l.status == 0 { // The status will be StatusOK if WriteHeader has not been called yet l.status = http.StatusOK } size, err := l.w.Write(b) l.size += size return size, err } // WriteHeader writes the status code for the Response func (l *responseLogger) WriteHeader(s int) { l.w.WriteHeader(s) l.status = s } // Status returns the response status code func (l *responseLogger) Status() int { return l.status } // Size returns the response size func (l *responseLogger) Size() int { return l.size } // Flush sends any buffered data to the client func (l *responseLogger) Flush() { if flusher, ok := l.w.(http.Flusher); ok { flusher.Flush() } } // loggingHandler is the http.Handler implementation for LoggingHandler type loggingHandler struct { handler http.Handler logger *log.Entry afterHandler afterHandler } type afterHandler func(l *log.Entry, r *http.Request) *log.Entry // NewLoggingHandler provides an http.Handler which logs requests to the HTTP server func NewLoggingHandler(logger *log.Entry, after afterHandler) func(h http.Handler) http.Handler { if after == nil { after = func(l *log.Entry, r *http.Request) *log.Entry { return l } } return func(h http.Handler) http.Handler { return loggingHandler{ handler: h, logger: logger, afterHandler: after, } } } func (h loggingHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) { t := time.Now() url := *req.URL responseLogger := &responseLogger{w: w} h.handler.ServeHTTP(responseLogger, req) duration := float64(time.Since(t)) / float64(time.Millisecond) h.afterHandler(h.logger.WithFields(log.Fields{ "remote": req.RemoteAddr, "host": GetHost(req), "request_protocol": req.Proto, "runtime": fmt.Sprintf("%0.3f", duration), "method": req.Method, "size": responseLogger.Size(), "status": responseLogger.Status(), "upstream": responseLogger.upstream, "request_useragent": req.UserAgent(), }), req).Info(url.RequestURI()) }