/// <summary>
/// Invokes an operation method.
/// </summary>
/// <typeparam name="TT">The task return type.</typeparam>
/// <param name="method">The method.</param>
/// <param name="args">The arguments.</param>
/// <param name="returnType">The real return type.</param>
/// <returns></returns>
protected virtual async Task <TT> InvokeOperationAsync <TT>(MethodInfo method, object[] args, Type returnType)
{
// build arguments
Dictionary <string, object> argsPayload = new Dictionary <string, object>();
ParameterInfo[] argsMethod = method.GetParameters();
for (int i = 0; i < args.Length; i++)
{
argsPayload[argsMethod[i].Name] = args[i];
}
// create request
RpcRequest req = new RpcRequest(_contractAttr.Name != null ? _contractAttr.Name : _typeInfo.Name, method.Name, argsPayload);
// serialize
byte[] requestBody = new ProtobufRpcSerializer().SerializeRequest(req);
RpcHeader header = new RpcHeader(RpcHeader.HEADER_VERSION, ProtobufRpcSerializer.SerializerName, RpcMessageType.Single);
// create headers
IDictionary <string, object> headers = new Dictionary <string, object>()
{
{ RpcHeader.HEADER_NAME, header.ToString() }
};
// ask or send
if (method.GetCustomAttribute <RpcOperationAttribute>().NoReply)
{
// send operation
await _channel.SendAsync(requestBody, headers);
return(default(TT));
}
else
{
Envelope res = await _channel.AskAsync(requestBody, _configuration.Timeout, headers);
// transform response
byte[] responseBody = res.Body;
// try and get response header
if (!res.Headers.TryGetValue(RpcHeader.HEADER_NAME, out object resHeaderData))
{
throw new InvalidOperationException("The response envelope is not a valid RPC message");
}
RpcHeader resHeader = new RpcHeader(Encoding.UTF8.GetString(resHeaderData as byte[]));
// deserialize response
if (!RpcSerializer.Serializers.TryGetValue(resHeader.Serializer, out IRpcSerializer deserializer))
{
throw new NotSupportedException("The response serializer is not supported");
}
// deserialize
RpcResponse resPayload = null;
if (method.ReturnType == typeof(Task))
{
// deserialize
resPayload = deserializer.DeserializeResponse(responseBody, typeof(void));
// return result
if (resPayload.IsSuccess)
{
return((TT)(object)true);
}
}
else
{
// deserialize
Type taskType = method.ReturnType.GetGenericArguments()[0];
resPayload = deserializer.DeserializeResponse(responseBody, taskType);
// return result
if (resPayload.IsSuccess)
{
return((TT)resPayload.Data);
}
}
// throw error
throw new RpcException(resPayload.Error);
}
}
