Is it OK to use gRPC to push data?

Question

I'm wondering if it's a good idea to push data from gRPC server to a client. Basically I want to use a pub/sub pattern with gRPC. The way I do is that I return a response stream on the server implementation that I never close. Then, the client has a never ending go routine in charge of reading this stream.

Here is an example:

service Service {
    rpc RegularChanges (Void) returns (stream Change) {}
}

On the server side:

func (self *MyServiceImpl) RegularChanges(in *pb.Void, stream pb.Service_RegularChangesServer) error {

    for {
        d, err := time.ParseDuration("1s")
        if err != nil {
            log.Fatalf("Cannot parse duration")
            break;
        }
        time.Sleep(d)
        stream.Send(&pb.Change{Name:"toto", Description:"status changed"})
    }
    return nil
}

On client:

for {
        change, err := streamChanges.Recv()
        if err != nil {
            log.Fatalf("Error retrieving change")
        } else {
            log.Println(change)
        }
}

I just began with go and gRPC but I know it's based on HTTP2, hence it should support pushing datas. However, I'm not sure this is the way gRPC should be used.

Answer 1

gRPC is intended to be used in this way.

You should still consider how the client should behave on failures and how you may want to re-balance across backends. If your connection is going across the Internet, you may also want to enable keepalive to detect connection breakages by providing KeepaliveParams to the client and server.