Hands-On Software Engineering with Golang

Bi-directional streaming RPCs

The last RPC mode that we will explore is bi-directional streaming. This mode combines client- and server-side streaming and provides us with two independent channels where the client and server can asynchronously publish and consume messages.

To understand how this mode works, let's examine the definition for an asynchronous Echo service:

message EchoMessage {  string message = 1;}service EchoService {  rpc Echo (stream EchoMessage) returns (stream EchoMessage);}

The server-side logic for the echo service is not that interesting. As shown in the following code snippet, the server runs a for loop where it reads the next message from the client and echoes it back. The server's for loop keeps executing until the ...