go grpc micro study

https://www.jianshu.com/p/00be93ed230c

protoc --proto_path=proto --proto_path=third_party --go_out=plugins=grpc:proto service.proto

docker build --tag=go-rpc .

docker run -it -p 8081:8081 go-rpc

https://www.jianshu.com/p/2265f56805fa
https://www.jianshu.com/p/774b38306c30
https://www.jianshu.com/p/85e9cfa16247

客户端 可以向 服务端 订阅 一个数据，服务端 就 可以利用 stream ，源源不断地 推送数据。

```
message User {  # type User struct
    string id = 1; # GetId() string
    string name = 2; # GetName() string
}

service Broadcast { # type BroadcastClient interface
    rpc CreateStream(Connect) returns (stream Message); 
    # CreateStream(ctx context.Context, in *Connect, opts ...grpc.CallOption) (Broadcast_CreateStreamClient, error)
    rpc BroadcastMessage(Message) returns (Close); 
    # BroadcastMessage(ctx context.Context, in *Message, opts ...grpc.CallOption) (*Close, error)
}
```