SignalR
SignalR is .Net’s solution to realtime communications. It enables the creation of hubs and then efficiently route all messages to all clients.
You can checkout this Hi-Lo Game which leverages SignalR (source).
The idea is that all messages from all player (and also the game engine) are broadcasted to all players (connect to.
The implementation
Server side
A cluster of connections is called a hub. The two main methods of our hub are the Guess and WriteToPageAsync methods:
/// <summary>
/// Called from the client when a player guesses the Mystery Number.
/// </summary>
/// <param name="user">Player's name</param>
/// <param name="guess">Player's guess</param>
/// <returns></returns>
public async Task Guess(string user, string guess)
{
_logger.LogInformation("{user} guessed {guess}", user, guess);
if (!int.TryParse(guess, out int guessedNumber))
{
var errorMessage = $"Your guess {guess} should be a number (ex: 10).";
_logger.LogError(errorMessage);
await WriteToPageAsync(user, errorMessage);
return;
}
await WriteToPageAsync(user, $"{user} guesses {guess}.");
var responseToGuess = _gameMaster.ValidateGuess(user, guessedNumber);
await WriteToPageAsync(GameMasterUser, MessageFrom(responseToGuess));
if (responseToGuess.Value == ResponseToGuess.Correct)
{
await CelebrateAsync(user);
await PrintStatisticsAsync();
await StartNewRoundAsync();
}
}
private async Task WriteToPageAsync(string user, string message)
{
_logger.LogInformation("Writing message {message} from {user}", message, user);
await Clients.All.SendAsync("WriteToPage", user, message);
}
They are, respectively, the entry and exit points for the GameHub.
The clients call Guess to validade the player’s guess and GameHub uses WriteToPageAsync to communicate back with the clients
(note the await Clients.All.SendAsync("WriteToPage", user, message); call).