Golang ClientConn.Write方法代码示例

func (s *httpService) handle(req *http.Request, sc *httputil.ServerConn, tls, sticky bool) (done bool) {
	req.Header.Set("X-Request-Start", strconv.FormatInt(time.Now().UnixNano()/int64(time.Millisecond), 10))
	req.Header.Set("X-Request-Id", random.UUID())

	var backend *httputil.ClientConn
	var stickyCookie *http.Cookie
	if sticky {
		backend, stickyCookie = s.getBackendSticky(req)
	} else {
		backend = s.getBackend()
	}
	if backend == nil {
		log.Println("no backend found")
		fail(sc, req, 503, "Service Unavailable")
		return
	}
	defer backend.Close()

	req.Proto = "HTTP/1.1"
	req.ProtoMajor = 1
	req.ProtoMinor = 1
	delete(req.Header, "Te")
	delete(req.Header, "Transfer-Encoding")

	if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
		// If we aren't the first proxy retain prior
		// X-Forwarded-For information as a comma+space
		// separated list and fold multiple headers into one.
		if prior, ok := req.Header["X-Forwarded-For"]; ok {
			clientIP = strings.Join(prior, ", ") + ", " + clientIP
		}
		req.Header.Set("X-Forwarded-For", clientIP)
	}
	if tls {
		req.Header.Set("X-Forwarded-Proto", "https")
	} else {
		req.Header.Set("X-Forwarded-Proto", "http")
	}
	// TODO: Set X-Forwarded-Port

	// Pass the Request-URI verbatim without any modifications
	req.URL.Opaque = strings.Split(strings.TrimPrefix(req.RequestURI, req.URL.Scheme+":"), "?")[0]

	if err := backend.Write(req); err != nil {
		log.Println("server write err:", err)
		// TODO: return error to client here
		return true
	}
	res, err := backend.Read(req)
	if res != nil {
		if stickyCookie != nil {
			res.Header.Add("Set-Cookie", stickyCookie.String())
		}
		if res.StatusCode == http.StatusSwitchingProtocols {
			res.Body = nil
		}
		if err := sc.Write(req, res); err != nil {
			if err != io.EOF && err != httputil.ErrPersistEOF {
				log.Println("client write err:", err)
				// TODO: log error
			}
			return true
		}
	}
	if err != nil {
		if err != io.EOF && err != httputil.ErrPersistEOF {
			log.Println("server read err:", err)
			// TODO: log error
			fail(sc, req, 502, "Bad Gateway")
		}
		return
	}

	// TODO: Proxy HTTP CONNECT? (example: Go RPC over HTTP)
	if res.StatusCode == http.StatusSwitchingProtocols {
		serverW, serverR := backend.Hijack()
		clientW, clientR := sc.Hijack()
		defer serverW.Close()
		done := make(chan struct{})
		go func() {
			serverR.WriteTo(clientW)
			if cw, ok := clientW.(writeCloser); ok {
				cw.CloseWrite()
			}
			close(done)
		}()
		clientR.WriteTo(serverW)
		serverW.(writeCloser).CloseWrite()
		<-done
		return true
	}

	return
}

func (s *httpService) handle(req *http.Request, sc *httputil.ServerConn, tls, sticky bool) {
	for {
		req.Header.Set("X-Request-Start", strconv.FormatInt(time.Now().UnixNano()/int64(time.Millisecond), 10))

		var backend *httputil.ClientConn
		var stickyCookie *http.Cookie
		if sticky {
			backend, stickyCookie = s.getBackendSticky(req)
		} else {
			backend = s.getBackend()
		}
		if backend == nil {
			log.Println("no backend found")
			fail(sc, req, 503, "Service Unavailable")
			return
		}

		if req.Method != "GET" && req.Method != "POST" && req.Method != "HEAD" &&
			req.Method != "OPTIONS" && req.Method != "PUT" && req.Method != "DELETE" && req.Method != "TRACE" {
			fail(sc, req, 405, "Method not allowed")
			return
		}

		req.Proto = "HTTP/1.1"
		req.ProtoMajor = 1
		req.ProtoMinor = 1
		delete(req.Header, "Te")
		delete(req.Header, "Transfer-Encoding")

		if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
			// If we aren't the first proxy retain prior
			// X-Forwarded-For information as a comma+space
			// separated list and fold multiple headers into one.
			if prior, ok := req.Header["X-Forwarded-For"]; ok {
				clientIP = strings.Join(prior, ", ") + ", " + clientIP
			}
			req.Header.Set("X-Forwarded-For", clientIP)
		}
		if tls {
			req.Header.Set("X-Forwarded-Proto", "https")
		} else {
			req.Header.Set("X-Forwarded-Proto", "http")
		}
		// TODO: Set X-Forwarded-Port

		if err := backend.Write(req); err != nil {
			log.Println("server write err:", err)
			return
		}
		res, err := backend.Read(req)
		if res != nil {
			if stickyCookie != nil {
				res.Header.Add("Set-Cookie", stickyCookie.String())
			}
			if res.StatusCode == http.StatusSwitchingProtocols {
				res.Body = nil
			}
			if err := sc.Write(req, res); err != nil {
				if err != io.EOF && err != httputil.ErrPersistEOF {
					log.Println("client write err:", err)
					// TODO: log error
				}
				return
			}
		}
		if err != nil {
			if err != io.EOF && err != httputil.ErrPersistEOF {
				log.Println("server read err:", err)
				// TODO: log error
				fail(sc, req, 502, "Bad Gateway")
			}
			return
		}

		// TODO: Proxy HTTP CONNECT? (example: Go RPC over HTTP)
		if res.StatusCode == http.StatusSwitchingProtocols {
			serverW, serverR := backend.Hijack()
			clientW, clientR := sc.Hijack()
			defer serverW.Close()
			done := make(chan struct{})
			go func() {
				serverR.WriteTo(clientW)
				if cw, ok := clientW.(writeCloser); ok {
					cw.CloseWrite()
				}
				close(done)
			}()
			clientR.WriteTo(serverW)
			serverW.(writeCloser).CloseWrite()
			<-done
			return
		}

		// close the backend connection, so we don't accidently send to
		// a closed socket on the backend
		backend.Close()

		// TODO: http pipelining
		req, err = sc.Read()
		if err != nil {
//.........这里部分代码省略.........

//.........这里部分代码省略.........
			w.dbgError("Could not negotiate tls handshake on %s : %s\n", address, err)
			return
		}

		// defer closing this connection as well
		defer tlsConn.Close()
	}

	// get a time reading on how long it took to negotiate ssl
	timestop = time.Now()
	sslHandshake := (timestop.Sub(timestart))

	// get our state
	if work.ssl {
		state := tlsConn.ConnectionState()
		w.dbg(2, "Handshake Complete: %t\n", state.HandshakeComplete)
		w.dbg(2, "Mutual: %t\n", state.NegotiatedProtocolIsMutual)
	}

	// debug
	w.dbg(3, "Converting to an HTTP client connection...\n")

	// convert to an http connection
	if work.ssl {
		client = httputil.NewProxyClientConn(tlsConn, nil)
	} else {
		client = httputil.NewProxyClientConn(myConn, nil)
	}

	// debug
	w.dbg(1, "Making GET request\n")

	// write our request to the socket
	err = client.Write(request)
	if err != nil {
		w.dbgError("Error writing request : %s\n", err)
		return
	}

	// read our response headers
	response, err := client.Read(request)
	if err != nil {
		// did we get a 400?
		if response.StatusCode == 400 {
			w.dbgError("400 response received.. \n")
			return
		}
		// did we get a 404?
		if response.StatusCode == 404 {
			w.dbgError("404 response received.. \n")
			return
		}
		// any other error, exit out
		w.dbgError("Error reading response : %s\n", err)
		return
	}

	w.dbg(1, "Status: %s\n", response.Status)

	// did we get a response?
	if len(response.Header) == 0 {
		w.dbgError("0 length response, something probably broke")
		return
	}

	// measure response header time