client

type Breaker interface {
	Call(func() error, time.Duration) error
	Fail()
	Success()
	Ready() bool
}

type Call struct {
	ServicePath   string            // The name of the service and method to call.
	ServiceMethod string            // The name of the service and method to call.
	Metadata      map[string]string //metadata
	ResMetadata   map[string]string
	Args          interface{} // The argument to the function (*struct).  提供rpc具体服务的func的参数
	Reply         interface{} // The reply from the function (*struct).   提供rpc具体服务的func的结果
	Error         error       // After completion, the error status.      一次rpc执行完成后 error状态
	Done          chan *Call  // Strobes when call is complete.
	Raw           bool        // raw message or not   是否为原始消息
}

type Client struct {
	Conn net.Conn // connection

	Plugins PluginContainer // 插件容器

	ServerMessageChan chan<- *protocol.Message
	// contains filtered or unexported fields
}

type FailMode int

type KVPair struct {
	Key   string
	Value string
}

type Option struct {
	// Group is used to select the services in the same group. Services set group info in their meta.
	// If it is empty, clients will ignore group.
	Group string // 设定services在相同的group便于service的隔离及管理；并且将group信息设置到meta data里；若未指定group 则client忽略

	// Retries retries to send
	Retries int // 重试次数

	// TLSConfig for tcp and quic
	TLSConfig *tls.Config // tls配置用于(tcp/quic协议)
	// kcp.BlockCrypt
	Block interface{} // 加密
	// RPCPath for http connection
	RPCPath string // http连接转为rpc请求 指定的path
	//ConnectTimeout sets timeout for dialing
	ConnectTimeout time.Duration // connection 有效期
	// ReadTimeout sets readdeadline for underlying net.Conns
	ReadTimeout time.Duration // 读有效期
	// WriteTimeout sets writedeadline for underlying net.Conns
	WriteTimeout time.Duration // 写有效期

	// BackupLatency is used for Failbackup mode. rpcx will sends another request if the first response doesn't return in BackupLatency time.
	BackupLatency time.Duration // Failbackup模式下，当第一个request在有效期内(latency time)未能返回结果，则rpcx会重新发送另一个request,两个request任意一个返回结果即认为请求成功

	// Breaker is used to config CircuitBreaker
	GenBreaker func() Breaker // 断路器

	SerializeType protocol.SerializeType // 编解码类型(一般client和server相同的编码格式)
	CompressType  protocol.CompressType  // 压缩类型

	Heartbeat         bool          // 是否为心跳信息
	HeartbeatInterval time.Duration // 心跳间隔
}

type RPCClient interface {
	Connect(network, address string) error                                                                                 // 连接
	Go(ctx context.Context, servicePath, serviceMethod string, args interface{}, reply interface{}, done chan *Call) *Call // 异步调用
	Call(ctx context.Context, servicePath, serviceMethod string, args interface{}, reply interface{}) error                // 同步调用
	SendRaw(ctx context.Context, r *protocol.Message) (map[string]string, []byte, error)                                   // 直连 发送原始内容
	Close() error                                                                                                          // 关闭connection

	RegisterServerMessageChan(ch chan<- *protocol.Message) //
	UnregisterServerMessageChan()

	IsClosing() bool
	IsShutdown() bool
}

type SelectMode int

type Selector interface {
	Select(ctx context.Context, servicePath, serviceMethod string, args interface{}) string
	UpdateServer(servers map[string]string)
}

type ServiceDiscovery interface {
	GetServices() []*KVPair                    // 获取注册的服务
	WatchService() chan []*KVPair              // 监听注册的服务
	RemoveWatcher(ch chan []*KVPair)           // 移除服务监听
	Clone(servicePath string) ServiceDiscovery // 复制
	Close()                                    // 关闭
}

type ServiceError string // 服务端错误字符串形式

type XClient interface {
	SetPlugins(plugins PluginContainer)            // 设定插件
	SetSelector(s Selector)                        // 服务路由模式:随机、轮训、加权轮询、加权ICMP(ping时间)、一致性hash、基于地理位置就近选择、用户自定义路由
	ConfigGeoSelector(latitude, longitude float64) // 指定地理位置
	Auth(auth string)                              // 鉴权

	Go(ctx context.Context, serviceMethod string, args interface{}, reply interface{}, done chan *Call) (*Call, error) // 异步请求
	Call(ctx context.Context, serviceMethod string, args interface{}, reply interface{}) error                         // 同步请求
	Broadcast(ctx context.Context, serviceMethod string, args interface{}, reply interface{}) error                    // 请求所有节点：请求成功只返回一个节点的结果；若是出现错误，也只会将一个节点error返回
	Fork(ctx context.Context, serviceMethod string, args interface{}, reply interface{}) error                         //
	SendRaw(ctx context.Context, r *protocol.Message) (map[string]string, []byte, error)                               // 自己封装protocol.Message 采用原始发送请求server
	Close() error                                                                                                      // 关闭clien
}