public SubscriptionInfo Unsubscribe(Topic topic, Subscriber subscriber)
{
topic.Requires("topic").IsNotNull();
subscriber.Requires("subscriber").IsNotNull();
if (isDisposed)
{
throw new ObjectDisposedException(MethodBase.GetCurrentMethod()?.DeclaringType?.Name,
"instance has been disposed");
}
var key = GetKey(topic, subscriber);
SubscriptionInfo subscriptionInfo;
if (subscriptions.TryRemove(key, out subscriptionInfo))
{
subscriptionInfo.CancelToken.Cancel();
if (!subscriber.LongLived || resourceCounter.Decrement(subscriptionInfo.Subscriber.Name) == 0)
{
amazonSnsFacade.UnsubscribeQueueFromTopic(subscriptionInfo.SubscriptionArn);
}
subscriptionInfo.CancelToken = null;
subscriptionInfo.SubscriptionArn = null;
}
return subscriptionInfo;
}
public void Publish(Topic topic, string subject, string message)
{
topic.Requires().IsNotNull();
subject.Requires().IsNotNullOrWhiteSpace();
message.Requires().IsNotNullOrWhiteSpace();
amazonSnsFacade.PublishMessageToTopic(topic.TopicArn, subject, message);
}
public bool IsSubscribed(Topic topic, Subscriber subscriber)
{
topic.Requires("topic").IsNotNull();
subscriber.Requires("subscriber").IsNotNull();
if (isDisposed)
{
throw new ObjectDisposedException(MethodBase.GetCurrentMethod()?.DeclaringType?.Name,
"instance has been disposed");
}
var key = GetKey(topic, subscriber);
return subscriptions.ContainsKey(key);
}
public Topic GetTopic(string channelName)
{
channelName.Requires("channelName").IsNotNullOrWhiteSpace();
var topicName = GetTopicName(channelName);
var topicArn = amazonSnsFacade.CreateOrRetrieveTopic(topicName);
if (topics.ContainsKey(channelName))
{
return topics[channelName];
}
var topic = new Topic(topicName, topicArn);
topics[channelName] = topic;
return topic;
}
public SubscriptionInfo Subscribe(Topic topic, Subscriber subscriber, Action<Message> messageHandler)
{
topic.Requires("topic").IsNotNull();
subscriber.Requires("subscriber").IsNotNull();
messageHandler.Requires("messageHandler").IsNotNull();
if (isDisposed)
{
throw new ObjectDisposedException(MethodBase.GetCurrentMethod()?.DeclaringType?.Name,
"instance has been disposed");
}
var key = GetKey(topic, subscriber);
return subscriptions.AddOrUpdate(key, k => AddSubscription(topic, subscriber, messageHandler),
(x, s) => UpdateSubscription(s, messageHandler));
}
private SubscriptionInfo AddSubscription(Topic topic, Subscriber subscriber, Action<Message> messageHandler)
{
var subscriptionInfo = new SubscriptionInfo
{
Topic = topic,
Subscriber = subscriber
};
amazonSqsFacade.SetSqsPolicyForSnsPublish(subscriber.QueueUrl, subscriber.QueueArn, topic.TopicArn);
subscriptionInfo.SubscriptionArn =
amazonSnsFacade.SubscribeQueueToTopic(subscriptionInfo.Subscriber.QueueArn,
subscriptionInfo.Topic.TopicArn);
if (subscriptionInfo.Subscriber.LongLived)
{
resourceCounter.Increment(subscriptionInfo.Subscriber.Name);
}
subscriptionInfo.CancelToken = queuePoller.Start(subscriptionInfo, messageHandler);
return subscriptionInfo;
}
public void Publish(Topic topic, string subject, string message)
{
topic.Requires("topic").IsNotNull();
subject.Requires("subject").IsNotNullOrWhiteSpace();
message.Requires("message").IsNotNullOrWhiteSpace();
if (isDisposed)
{
throw new ObjectDisposedException(MethodBase.GetCurrentMethod()?.DeclaringType?.Name,
"instance has been disposed");
}
amazonSnsFacade.PublishMessageToTopic(topic.TopicArn, subject, message);
}
private static string GetKey(Topic topic, Subscriber subscriber)
{
return string.Concat(topic.Name, "-", subscriber.Name);
}