serverStream method
Implementation
Future<DynamicStream> serverStream(String service, String method,
GenericMessage req,
{Map<String, String>? metadata, Duration? timeout}) async {
final m = _method(service, method);
final stream = await _channel.serverStream(
m.path, _BoundMessage(m.input!, req, _model),
metadata: metadata, timeout: timeout);
return DynamicStream(stream, m.output!, _model);
}