private static async Task SendMessageAsync(ChannelBase channel)
        {
            var chatService = new ChatService.ChatServiceClient(channel);

            try
            {
                var messageContent = string.Empty;
                while (messageContent != "exit")
                {
                    Console.WriteLine("Enter message: ");
                    messageContent = Console.ReadLine();

                    var message = new Message
                    {
                        Login   = _login,
                        Time    = DateTime.UtcNow.ToTimestamp(),
                        Content = messageContent ?? string.Empty
                    };

                    await chatService.SendAsync(message);
                }
            }
            catch (Exception e)
            {
                Console.WriteLine(e);
                Console.ReadKey();
            }

            CancellationTokenSource.Cancel();
        }