How to get message value in gRPC stream interceptor-CodePudding

I have implement a gRPC stream interceptor in Server like this:

// Service define:
// rpc searchProducts(google.protobuf.StringValue) returns (stream Product);

func (w *wrappedStream) RecvMsg(m interface{}) error {
    log.Printf("%T, %v", m, m)
    return w.ServerStream.RecvMsg(m)
}

// Log print:
// *wrapperspb.StringValue,

It can print the message type using %T correctly, but the message value printing by %v is just a blank.

I'm sure that Server received the right message, because it replied Client the right thing.

The interceptor wrapper RecvMsg is not working in Client too.

CodePudding user response：

w.ServerStream.RecvMsg(m) will unmarshall data into m, just move print after RecvMsg() call.

func (w *wrappedStream) RecvMsg(m interface{}) error {
    err := w.ServerStream.RecvMsg(m)
    log.Printf("%T, %v", m, m)
    return err
}