/// <summary>
/// Adds a new topic message for everyone with a specific topic and type
/// </summary>
/// <param name="senderId">The Id of the client that sent the message</param>
/// <param name="type">The topic type of the message</param>
/// <param name="content">The content of the message</param>
/// <param name="expirationDate">The date at which the message should expire</param>
/// <exception cref="ArgumentNullException">Thrown when the content of the message is null or empty</exception>
/// <exception cref="ArgumentException">Thrown when the Id of the sender is invalid or not registered into the server</exception>
public async Task AddTopicMessageAsync(Guid senderId, TopicMessageType type, string content, DateTime expirationDate)
{
if (string.IsNullOrEmpty(content))
{
throw new ArgumentNullException(nameof(content), "Cannot add a message with null content to the queue");
}
lock (mClients)
{
if (mClients.All(client => client.Id != senderId))
{
throw new ArgumentException($"Cannot send message from an inexistent client. There is no registered client with id: {senderId}", nameof(senderId));
}
}
try
{
await Task.Run(() =>
{
var message = new TopicMessage(senderId, type, content, expirationDate);
lock (mTopicMessages)
{
mTopicMessages.Add(message);
}
}, mCancellationTokenSource.Token).ConfigureAwait(false);
}
catch (TaskCanceledException)
{
Debug.WriteLine($"Task {nameof(AddTopicMessageAsync)} cancelled");
}
}
/// <summary>
/// Retrieve all the available topic messages that have a certain type
/// </summary>
/// <param name="topicMessageType">The type of the topic messages to be fetched</param>
/// <returns>A collection of topic messages that are of the given type</returns>
public async Task <IList <TopicMessage> > GetTopicMessagesAsync(TopicMessageType topicMessageType)
{
try
{
return(await Task.Run(() =>
{
lock (mTopicMessages)
{
return mTopicMessages.Where(message => message.Type == topicMessageType).ToList();
}
}, mCancellationTokenSource.Token).ConfigureAwait(false));
}
catch (TaskCanceledException)
{
Debug.WriteLine($"Task {nameof(GetTopicMessagesAsync)} cancelled");
return(new List <TopicMessage>());
}
}
/// <summary>
/// Create a new topic message that has an exact topic and type
/// </summary>
/// <param name="senderId">The Id of the <see cref="Client"/> that created the message</param>
/// <param name="type">The type of the message</param>
/// <param name="content">The content of the message</param>
/// <param name="expiresAt">The time at which the message should expire</param>
public TopicMessage(Guid senderId, TopicMessageType type, string content, DateTime expiresAt) : base(senderId, content)
{
Type = type;
ExpiresAt = expiresAt;
}
