Golang Response.Index Examples

Example #1

File: store.go Project: radcheb/influxdb

// handleExecConn reads a command from the connection and executes it.
func (s *Store) handleExecConn(conn net.Conn) {
	defer s.wg.Done()

	// Read and execute command.
	err := func() error {
		// Read marker message.
		b := make([]byte, 4)
		if _, err := io.ReadFull(conn, b); err != nil {
			return fmt.Errorf("read magic: %s", err)
		} else if string(b) != ExecMagic {
			return fmt.Errorf("invalid exec magic: %q", string(b))
		}

		// Read command size.
		var sz uint64
		if err := binary.Read(conn, binary.BigEndian, &sz); err != nil {
			return fmt.Errorf("read size: %s", err)
		}

		// Read command.
		buf := make([]byte, sz)
		if _, err := io.ReadFull(conn, buf); err != nil {
			return fmt.Errorf("read command: %s", err)
		}

		// Ensure command can be deserialized before applying.
		if err := proto.Unmarshal(buf, &internal.Command{}); err != nil {
			return fmt.Errorf("unable to unmarshal command: %s", err)
		}

		// Apply against the raft log.
		if err := s.apply(buf); err != nil {
			return fmt.Errorf("apply: %s", err)
		}
		return nil
	}()

	// Build response message.
	var resp internal.Response
	resp.OK = proto.Bool(err == nil)
	resp.Index = proto.Uint64(s.raft.LastIndex())
	if err != nil {
		resp.Error = proto.String(err.Error())
	}

	// Encode response back to connection.
	if b, err := proto.Marshal(&resp); err != nil {
		panic(err)
	} else if err = binary.Write(conn, binary.BigEndian, uint64(len(b))); err != nil {
		s.Logger.Printf("unable to write exec response size: %s", err)
	} else if _, err = conn.Write(b); err != nil {
		s.Logger.Printf("unable to write exec response: %s", err)
	}
	conn.Close()
}

Example #2

File: store.go Project: ASAPPinc/influxdb

// handleExecConn reads a command from the connection and executes it.
func (s *Store) handleExecConn(conn net.Conn) {
	defer s.wg.Done()

	// Nodes not part of the raft cluster may initiate remote exec commands
	// but may not know who the current leader of the cluster.  If we are not
	// the leader, proxy the request to the current leader.
	if !s.IsLeader() {
		leaderConn, err := net.DialTimeout("tcp", s.Leader(), 10*time.Second)
		if err != nil {
			s.Logger.Printf("dial leader: %v", err)
			return
		}
		defer leaderConn.Close()
		leaderConn.Write([]byte{MuxExecHeader})

		if err := proxy(leaderConn.(*net.TCPConn), conn.(*net.TCPConn)); err != nil {
			s.Logger.Printf("leader proxy error: %v", err)
		}
		conn.Close()
		return
	}

	// Read and execute command.
	err := func() error {
		// Read marker message.
		b := make([]byte, 4)
		if _, err := io.ReadFull(conn, b); err != nil {
			return fmt.Errorf("read magic: %s", err)
		} else if string(b) != ExecMagic {
			return fmt.Errorf("invalid exec magic: %q", string(b))
		}

		// Read command size.
		var sz uint64
		if err := binary.Read(conn, binary.BigEndian, &sz); err != nil {
			return fmt.Errorf("read size: %s", err)
		}

		// Read command.
		buf := make([]byte, sz)
		if _, err := io.ReadFull(conn, buf); err != nil {
			return fmt.Errorf("read command: %s", err)
		}

		// Ensure command can be deserialized before applying.
		if err := proto.Unmarshal(buf, &internal.Command{}); err != nil {
			return fmt.Errorf("unable to unmarshal command: %s", err)
		}

		// Apply against the raft log.
		if err := s.apply(buf); err != nil {
			return fmt.Errorf("apply: %s", err)
		}
		return nil
	}()

	// Build response message.
	var resp internal.Response
	resp.OK = proto.Bool(err == nil)
	resp.Index = proto.Uint64(s.raftState.lastIndex())
	if err != nil {
		resp.Error = proto.String(err.Error())
	}

	// Encode response back to connection.
	if b, err := proto.Marshal(&resp); err != nil {
		panic(err)
	} else if err = binary.Write(conn, binary.BigEndian, uint64(len(b))); err != nil {
		s.Logger.Printf("unable to write exec response size: %s", err)
	} else if _, err = conn.Write(b); err != nil {
		s.Logger.Printf("unable to write exec response: %s", err)
	}
	conn.Close()
}