Fabric 1.0源代码笔记 之 gossip（流言算法） #GossipServer（Gossip服务端）

1、GossipServer概述

GossipServer相关代码，分布在protos/gossip、gossip/comm目录下。目录结构如下：

• protos/gossip目录：
  ????* message.pb.go，GossipClient接口定义及实现，GossipServer接口定义。
• gossip/comm目录：
  ???? comm.go，Comm接口定义。
  ???? conn.go，connFactory接口定义，以及connectionStore结构体及方法。
  ???? comm_impl.go，commImpl结构体及方法（同时实现GossipServer接口/Comm接口/connFactory接口）。
  ???? demux.go，ChannelDeMultiplexer结构体及方法。

2、GossipClient接口定义及实现

2.1、GossipClient接口定义

type GossipClient interface {
????// GossipStream is the gRPC stream used for sending and receiving messages
????GossipStream(ctx context.Context, opts ...grpc.CallOption) (Gossip_GossipStreamClient, error)
????// Ping is used to probe a remote peer‘s aliveness
????Ping(ctx context.Context, in *Empty, opts ...grpc.CallOption) (*Empty, error)
}
//代码在protos/gossip/message.pb.go

2.2、GossipClient接口实现

type gossipClient struct {
????cc *grpc.ClientConn
}

func NewGossipClient(cc *grpc.ClientConn) GossipClient {
????return &gossipClient{cc}
}

func (c *gossipClient) GossipStream(ctx context.Context, opts ...grpc.CallOption) (Gossip_GossipStreamClient, error) {
????stream, err := grpc.NewClientStream(ctx, &_Gossip_serviceDesc.Streams[0], c.cc, "/gossip.Gossip/GossipStream", opts...)
????if err != nil {
????????return nil, err
????}
????x := &gossipGossipStreamClient{stream}
????return x, nil
}

func (c *gossipClient) Ping(ctx context.Context, in *Empty, opts ...grpc.CallOption) (*Empty, error) {
????out := new(Empty)
????err := grpc.Invoke(ctx, "/gossip.Gossip/Ping", in, out, c.cc, opts...)
????if err != nil {
????????return nil, err
????}
????return out, nil
}
//代码在protos/gossip/message.pb.go

2.3、Gossip_GossipStreamClient接口定义及实现

type Gossip_GossipStreamClient interface {
????Send(*Envelope) error
????Recv() (*Envelope, error)
????grpc.ClientStream
}

type gossipGossipStreamClient struct {
????grpc.ClientStream
}

func (x *gossipGossipStreamClient) Send(m *Envelope) error {
????return x.ClientStream.SendMsg(m)
}

func (x *gossipGossipStreamClient) Recv() (*Envelope, error) {
????m := new(Envelope)
????if err := x.ClientStream.RecvMsg(m); err != nil {
????????return nil, err
????}
????return m, nil
}
//代码在protos/gossip/message.pb.go

3、GossipServer接口定义

3.1、GossipServer接口定义

type GossipServer interface {
????// GossipStream is the gRPC stream used for sending and receiving messages
????GossipStream(Gossip_GossipStreamServer) error
????// Ping is used to probe a remote peer‘s aliveness
????Ping(context.Context, *Empty) (*Empty, error)
}

func RegisterGossipServer(s *grpc.Server, srv GossipServer) {
????s.RegisterService(&_Gossip_serviceDesc, srv)
}

func _Gossip_GossipStream_Handler(srv interface{}, stream grpc.ServerStream) error {
????return srv.(GossipServer).GossipStream(&gossipGossipStreamServer{stream})
}

func _Gossip_Ping_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
????in := new(Empty)
????if err := dec(in); err != nil {
????????return nil, err
????}
????if interceptor == nil {
????????return srv.(GossipServer).Ping(ctx, in)
????}
????info := &grpc.UnaryServerInfo{
????????Server:     srv,
????????FullMethod: "/gossip.Gossip/Ping",
????}
????handler := func(ctx context.Context, req interface{}) (interface{}, error) {
????????return srv.(GossipServer).Ping(ctx, req.(*Empty))
????}
????return interceptor(ctx, in, info, handler)
}

var _Gossip_serviceDesc = grpc.ServiceDesc{
????ServiceName: "gossip.Gossip",
????HandlerType: (*GossipServer)(nil),
????Methods: []grpc.MethodDesc{
????????{
????????????MethodName: "Ping",
????????????Handler:    _Gossip_Ping_Handler,
????????},
????},
????Streams: []grpc.StreamDesc{
????????{
????????????StreamName:    "GossipStream",
????????????Handler:       _Gossip_GossipStream_Handler,
????????????ServerStreams: true,
????????????ClientStreams: true,
????????},
????},
????Metadata: "gossip/message.proto",
}
//代码在protos/gossip/message.pb.go

3.2、Gossip_GossipStreamServer接口定义及实现

type Gossip_GossipStreamServer interface {
????Send(*Envelope) error
????Recv() (*Envelope, error)
????grpc.ServerStream
}

type gossipGossipStreamServer struct {
????grpc.ServerStream
}

func (x *gossipGossipStreamServer) Send(m *Envelope) error {
????return x.ServerStream.SendMsg(m)
}

func (x *gossipGossipStreamServer) Recv() (*Envelope, error) {
????m := new(Envelope)
????if err := x.ServerStream.RecvMsg(m); err != nil {
????????return nil, err
????}
????return m, nil
}
//代码在protos/gossip/message.pb.go

4、Comm接口/connFactory接口定义

4.1、Comm接口定义

type Comm interface {
????//返回此实例的 PKI id
????GetPKIid() common.PKIidType
????//向节点发送消息
????Send(msg *proto.SignedGossipMessage, peers ...*RemotePeer)
????//探测远程节点是否有响应
????Probe(peer *RemotePeer) error
????//握手验证远程节点
????Handshake(peer *RemotePeer) (api.PeerIdentityType, error)
????Accept(common.MessageAcceptor) <-chan proto.ReceivedMessage
????//获取怀疑脱机节点的只读通道
????PresumedDead() <-chan common.PKIidType
????//关闭到某个节点的连接
????CloseConn(peer *RemotePeer)
????//关闭
????Stop()
}
//代码在gossip/comm/comm.go

4.2、connFactory接口定义

type connFactory interface {
????createConnection(endpoint string, pkiID common.PKIidType) (*connection, error)
}
//代码在gossip/comm/conn.go

5、commImpl结构体及方法（同时实现GossipServer接口/Comm接口/connFactory接口）

5.1、commImpl结构体定义

type commImpl struct {
????selfCertHash   []byte
????peerIdentity   api.PeerIdentityType
????idMapper       identity.Mapper
????logger         *logging.Logger
????opts           []grpc.DialOption
????secureDialOpts func() []grpc.DialOption
????connStore      *connectionStore
????PKIID          []byte
????deadEndpoints  chan common.PKIidType
????msgPublisher   *ChannelDeMultiplexer
????lock           *sync.RWMutex
????lsnr           net.Listener
????gSrv           *grpc.Server
????exitChan       chan struct{}
????stopWG         sync.WaitGroup
????subscriptions  []chan proto.ReceivedMessage
????port           int
????stopping       int32
}
//代码在gossip/comm/comm_impl.go

区块链教程Fabric1.0源代码分析流言算法Gossip服务端一

原文：http://blog.51cto.com/14041296/2311306