moved some goroutines to separate functions for improved readability

client.go

@@ -1675,16 +1675,175 @@ func (cts *ClientConn) FindClientRpxById(id uint64) *ClientRpx {
 	return crpx
 }
 
+func (cts *ClientConn) server_pipe_to_ws_target(crpx* ClientRpx, conn net.Conn, wg *sync.WaitGroup) {
+	var buf [4096]byte
+	var n int
+	var err error
+
+	defer wg.Done()
+
+	for {
+		n, err = crpx.pr.Read(buf[:])
+		if n > 0 {
+			var err2 error
+			_, err2 = conn.Write(buf[:n])
+			if err2 != nil {
+				cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to write websocket for rpx(%d) - %s", crpx.id, err2.Error())
+				break
+			}
+		}
+		if err != nil {
+			if errors.Is(err, io.EOF) { break }
+			cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to read pipe for rpx(%d) - %s", crpx.id, err.Error())
+			break
+		}
+	}
+}
+
+func (cts *ClientConn) proxy_ws(crpx *ClientRpx, raw_req []byte, req *http.Request) error {
+	var l_wg sync.WaitGroup
+	var conn net.Conn
+	var resp *http.Response
+	var r *bufio.Reader
+	var buf [4096]byte
+	var n int
+	var err error
+
+	if cts.C.rpx_target_tls != nil {
+		var dialer *tls.Dialer
+		dialer = &tls.Dialer{
+			NetDialer: &net.Dialer{},
+			Config: cts.C.rpx_target_tls,
+		}
+		conn, err = dialer.DialContext(crpx.ctx, "tcp", cts.C.rpx_target_addr) // TODO: no hard coding
+	} else {
+		var dialer *net.Dialer
+		dialer = &net.Dialer{}
+		conn, err = dialer.DialContext(crpx.ctx, "tcp", cts.C.rpx_target_addr) // TODO: no hard coding
+	}
+	if err != nil {
+		return fmt.Errorf("failed to dial websocket for rpx(%d) - %s", crpx.id, err.Error())
+	}
+	defer conn.Close()
+
+	// TODO: make this atomic?
+	crpx.ws_conn = conn
+
+	// write the raw request line and headers as sent by the server.
+	// for the upgrade request, i assume no payload.
+	_, err = conn.Write(raw_req)
+	if err != nil {
+		return fmt.Errorf("failed to write websocket request for rpx(%d) - %s", crpx.id, err.Error())
+	}
+
+	r = bufio.NewReader(conn)
+	resp, err = http.ReadResponse(r, req)
+	if err != nil {
+		return fmt.Errorf("failed to write websocket response for rpx(%d) - %s", crpx.id, err.Error())
+	}
+	defer resp.Body.Close()
+
+	err = cts.psc.Send(MakeRpxStartPacket(crpx.id, get_http_resp_line_and_headers(resp)))
+	if err != nil {
+		return fmt.Errorf("failed to send rpx(%d) WebSocket headers to server - %s", crpx.id, err.Error())
+	}
+
+	if resp.StatusCode != http.StatusSwitchingProtocols {
+		// websock upgrade failed. let the code jump to the done
+		// label to skip reading from the pipe. the server side
+		// has the code to ensure no content-length. and the upgrade
+		// fails, the pipe below will be pending forever as the server
+		// side doesn't send data and there's no feeding to the pipe.
+		return fmt.Errorf("protocol switching failed for rpx(%d)", crpx.id)
+	}
+
+	// unlike with the normal request, the actual pipe is not read
+	// until the initial switching protocol response is received.
+
+	l_wg.Add(1)
+	go cts.server_pipe_to_ws_target(crpx, conn, &l_wg)
+
+	for {
+		n, err = conn.Read(buf[:])
+		if n > 0 {
+			var err2 error
+			err2 = cts.psc.Send(MakeRpxDataPacket(crpx.id, buf[:n]))
+			if err2 != nil {
+				crpx.ReqStop() // to break server_pipe_ws_target. don't care about multiple stops
+				return fmt.Errorf("failed to send rpx(%d) data to server - %s", crpx.id, err2.Error())
+			}
+		}
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				cts.psc.Send(MakeRpxEofPacket(crpx.id))
+				cts.C.log.Write(cts.Sid, LOG_DEBUG, "WebSocket rpx(%d) closed by server", crpx.id)
+				break
+			}
+
+			crpx.ReqStop() // to break server_pipe_ws_target. don't care about multiple stops
+			return fmt.Errorf("failed to read WebSocket rpx(%d) - %s", crpx.id, err.Error())
+		}
+	}
+
+	// wait until the pipe reading(from the server side) goroutine is over
+	l_wg.Wait()
+	return nil
+}
+
+func (cts *ClientConn) proxy_http(crpx *ClientRpx, req *http.Request) error {
+	var tr *http.Transport
+	var resp *http.Response
+	var buf [4096]byte
+	var n int
+	var err error
+
+	tr = &http.Transport {
+		DisableKeepAlives: true, // this implementation can't support keepalive..
+	}
+	if cts.C.rpx_target_tls != nil {
+		tr.TLSClientConfig = cts.C.rpx_target_tls
+	}
+
+	resp, err = tr.RoundTrip(req)
+	if err != nil {
+		return fmt.Errorf("failed to send rpx(%d) request - %s", crpx.id, err.Error())
+	}
+
+	defer resp.Body.Close()
+
+	err = cts.psc.Send(MakeRpxStartPacket(crpx.id, get_http_resp_line_and_headers(resp)))
+	if err != nil {
+		return fmt.Errorf("failed to send rpx(%d) status and headers to server - %s", crpx.id, err.Error())
+	}
+
+	for {
+		n, err = resp.Body.Read(buf[:])
+		if n > 0 {
+			var err2 error
+			err2 = cts.psc.Send(MakeRpxDataPacket(crpx.id, buf[:n]))
+			if err2 != nil {
+				return fmt.Errorf("failed to send rpx(%d) data to server - %s", crpx.id, err2.Error())
+			}
+		}
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				break
+			}
+			return fmt.Errorf("failed to read response body for rpx(%d) - %s", crpx.id, err.Error())
+		}
+	}
+
+	return nil
+}
+
 func (cts *ClientConn) RpxLoop(crpx *ClientRpx, data []byte, wg *sync.WaitGroup) {
 	var sc *bufio.Scanner
 	var line string
 	var flds []string
-	var buf [4096]byte
 	var req_meth string
 	var req_path string
 	//var req_proto string
 	var req *http.Request
-	var n int
 	var err error
 
 	defer wg.Done()
@@ -1721,7 +1880,6 @@ func (cts *ClientConn) RpxLoop(crpx *ClientRpx, data []byte, wg *sync.WaitGroup)
 			k = strings.TrimSpace(flds[0])
 			v = strings.TrimSpace(flds[1])
 			req.Header.Add(k, v)
-//fmt.Printf ("ADDING HEADER %s: %v\n", k, v)
 		}
 	}
 	err = sc.Err()
@@ -1732,163 +1890,14 @@ func (cts *ClientConn) RpxLoop(crpx *ClientRpx, data []byte, wg *sync.WaitGroup)
 
 	if strings.EqualFold(req.Header.Get("Upgrade"), "websocket") && strings.Contains(strings.ToLower(req.Header.Get("Connection")), "upgrade") {
 		// websocket
-		var done_chan chan struct{}
+		err = cts.proxy_ws(crpx, data, req)
-
-		var conn net.Conn
-		var resp *http.Response
-		var r *bufio.Reader
-
-		if cts.C.rpx_target_tls != nil {
-			var dialer *tls.Dialer
-			dialer = &tls.Dialer{
-				NetDialer: &net.Dialer{},
-				Config: cts.C.rpx_target_tls,
-			}
-			conn, err = dialer.DialContext(crpx.ctx, "tcp", cts.C.rpx_target_addr) // TODO: no hard coding
-		} else {
-			var dialer *net.Dialer
-			dialer = &net.Dialer{}
-			conn, err = dialer.DialContext(crpx.ctx, "tcp", cts.C.rpx_target_addr) // TODO: no hard coding
-		}
-		if err != nil {
-			cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to dial websocket for rpx(%d) - %s", crpx.id, err.Error())
-			goto done
-		}
-		defer conn.Close()
-
-		// TODO: make this atomic?
-		crpx.ws_conn = conn
-
-		// write the raw request line and headers as sent by the server.
-		// for the upgrade request, i assume no payload.
-		_, err = conn.Write(data)
-		if err != nil {
-			cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to write websocket request for rpx(%d) - %s", crpx.id, err.Error())
-			goto done
-		}
-
-		r = bufio.NewReader(conn)
-		resp, err = http.ReadResponse(r, req)
-		if err != nil {
-			cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to write websocket response for rpx(%d) - %s", crpx.id, err.Error())
-			goto done
-		}
-		defer resp.Body.Close()
-
-		err = cts.psc.Send(MakeRpxStartPacket(crpx.id, get_http_resp_line_and_headers(resp)))
-		if err != nil {
-			cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to send rpx(%d) WebSocket headers to server - %s", crpx.id, err.Error())
-			goto done
-		}
-
-		if resp.StatusCode != http.StatusSwitchingProtocols {
-			// websock upgrade failed. let the code jump to the done
-			// label to skip reading from the pipe. the server side
-			// has the code to ensure no content-length. and the upgrade
-			// fails, the pipe below will be pending forever as the server
-			// side doesn't send data and there's no feeding to the pipe.
-			cts.C.log.Write(cts.Sid, LOG_INFO, "Protocol switching failed for rpx(%d)", crpx.id)
-			goto done
-		}
-
-		// unlike with the normal request, the actual pipe is not read
-		// until the initial switching protocol response is received.
-
-		wg.Add(1)
-		done_chan = make(chan struct{}, 5)
-		go func() {
-			var buf [4096]byte
-			var n int
-			var err error
-
-			defer wg.Done()
-			for {
-				n, err = crpx.pr.Read(buf[:])
-				if n > 0 {
-					var err2 error
-					_, err2 = conn.Write(buf[:n])
-					if err2 != nil {
-						cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to write websocket for rpx(%d) - %s", crpx.id, err2.Error())
-						break
-					}
-				}
-				if err != nil {
-					if errors.Is(err, io.EOF) { break }
-					cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to read pipe for rpx(%d) - %s", crpx.id, err.Error())
-					break
-				}
-			}
-			done_chan <- struct{}{}
-		}()
-
-		for {
-			n, err = conn.Read(buf[:])
-			if n > 0 {
-				var err2 error
-				err2 = cts.psc.Send(MakeRpxDataPacket(crpx.id, buf[:n]))
-				if err2 != nil {
-					cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to send rpx(%d) data to server - %s", crpx.id, err2.Error())
-					break
-				}
-			}
-			if err != nil {
-				if errors.Is(err, io.EOF) {
-					cts.psc.Send(MakeRpxEofPacket(crpx.id))
-					cts.C.log.Write(cts.Sid, LOG_DEBUG, "WebSocket rpx(%d) closed by server", crpx.id)
-					break
-				}
-				cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to read WebSocket rpx(%d) - %s", crpx.id, err.Error())
-				break
-			}
-		}
-
-		// wait until the pipe reading(from the server side) goroutine is over
-		<-done_chan
 	} else {
-		var tr *http.Transport
+		// normal http
-		var resp *http.Response
+		err = cts.proxy_http(crpx, req)
-
+	}
-		tr = &http.Transport {
+	if err != nil {
-			DisableKeepAlives: true, // this implementation can't support keepalive..
+		cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to proxy rpx(%d) - %s", crpx.id, err.Error())
-		}
+		goto done
-		if cts.C.rpx_target_tls != nil {
-			tr.TLSClientConfig = cts.C.rpx_target_tls
-		}
-//fmt.Printf("%+v\n", req)
-		resp, err = tr.RoundTrip(req)
-		if err != nil {
-			cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to send rpx(%d) request - %s", crpx.id, err.Error())
-			goto done
-		}
-
-		defer resp.Body.Close()
-
-		err = cts.psc.Send(MakeRpxStartPacket(crpx.id, get_http_resp_line_and_headers(resp)))
-		if err != nil {
-			cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to send rpx(%d) status and headers to server - %s", crpx.id, err.Error())
-			goto done
-		}
-
-		for {
-			n, err = resp.Body.Read(buf[:])
-//fmt.Printf ("READ RESPONSE [%s], %d, %v\n", string(buf[:n]), n, err)
-			if n > 0 {
-				var err2 error
-				err2 = cts.psc.Send(MakeRpxDataPacket(crpx.id, buf[:n]))
-				if err2 != nil {
-					cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to send rpx(%d) data to server - %s", crpx.id, err2.Error())
-					break
-				}
-			}
-			if err != nil {
-				if errors.Is(err, io.EOF) {
-					break
-				}
-				cts.C.log.Write(cts.Sid, LOG_ERROR, "Failed to read response body for rpx(%d) - %s", crpx.id, err.Error())
-				break
-			}
-		}
-//fmt.Printf ("READ RESPONSE LOOP IS OVER\n")
 	}
 
 done:
@@ -1899,6 +1908,7 @@ done:
 	cts.C.log.Write(cts.Sid, LOG_INFO, "Ending rpx(%d) read loop", crpx.id)
 
 	crpx.ReqStop()
+
 	cts.rpx_mtx.Lock()
 	delete(cts.rpx_map, crpx.id)
 	cts.rpx_mtx.Unlock()