com.amazonaws.auth.policy.conditions.ConditionFactory Java Examples

public void connectToTopic(boolean callerIsMaster, int maxAttempts, String userAccountPrincipalId, String userARN) throws Exception {
	
	
	// try up to max attempts to connect to pre-existing topic
	for (int i=0; i<maxAttempts; i++) {
		
		logger.debug("connectToTopic() attempt: " + (i+1));
		
		ListTopicsResult listResult = snsClient.listTopics();
		List<Topic> topics = listResult.getTopics();
		
		while(topics != null) {
			
			for (Topic topic : topics) {

				// note we do index of match....
				if (topic.getTopicArn().indexOf(snsControlTopicName) != -1) {
					snsTopicARN = topic.getTopicArn();
					logger.info("Found existing SNS topic by name: "+snsControlTopicName + " @ " + snsTopicARN);
					break;
				}
			}

			String nextToken = listResult.getNextToken();
			
			if (nextToken != null && snsTopicARN == null) {
				listResult = snsClient.listTopics(nextToken);
				topics = listResult.getTopics();
				
			} else {
				break;
			}
		}
		
		// if consumer, retry, otherwise is master, so just exit quick to create...
		if (snsTopicARN == null && !callerIsMaster) {
			Thread.currentThread().sleep(1000);
			continue;
		} else {
			break; // exit;
		}
	}
	
	
	
	// if master only he can create...
	if (snsTopicARN == null && callerIsMaster) {
		this.snsControlTopicName = this.snsControlTopicName.substring(0,(snsControlTopicName.length() > 80 ? 80 : this.snsControlTopicName.length()));
		
		logger.info("Attempting to create new SNS control channel topic by name: "+this.snsControlTopicName);
		
		CreateTopicResult createTopicResult = snsClient.createTopic(this.snsControlTopicName);
		snsTopicARN = createTopicResult.getTopicArn();
		snsClient.addPermission(snsTopicARN, "Permit_SNSAdd", 
								Arrays.asList(new String[]{userARN}), 
								Arrays.asList(new String[]{"Publish","Subscribe","Receive"}));
		logger.info("Created new SNS control channel topic by name: "+this.snsControlTopicName + " @ " + snsTopicARN);
		
	} else if (snsTopicARN == null) {
		throw new Exception("Worker() cannot start, snsControlTopicName has yet to be created by master?: " + this.snsControlTopicName);
	}
	
	// http://www.jorgjanke.com/2013/01/aws-sns-topic-subscriptions-with-sqs.html
	
	// create SQS queue to get SNS notifications (max 80 len)
	String prefix =  ("s3bktLoaderCC_" + mySourceIdentifier);
	String sqsQueueName = prefix.substring(0,(prefix.length() > 80 ? 80 : prefix.length()));
	
	CreateQueueResult createQueueResult = sqsClient.createQueue(sqsQueueName);
	this.sqsQueueUrl = createQueueResult.getQueueUrl();
	this.sqsQueueARN = sqsClient.getQueueAttributes(sqsQueueUrl, Arrays.asList(new String[]{"QueueArn"})).getAttributes().get("QueueArn");

	Statement statement = new Statement(Effect.Allow)
							.withActions(SQSActions.SendMessage)
							 .withPrincipals(new Principal("*"))
							 .withConditions(ConditionFactory.newSourceArnCondition(snsTopicARN))
							 .withResources(new Resource(sqsQueueARN));
	Policy policy = new Policy("SubscriptionPermission").withStatements(statement);

	HashMap<String, String> attributes = new HashMap<String, String>();
	attributes.put("Policy", policy.toJson());
	SetQueueAttributesRequest request = new SetQueueAttributesRequest(sqsQueueUrl, attributes);
	sqsClient.setQueueAttributes(request);

	logger.info("Created SQS queue: " + sqsQueueARN + " @ " + sqsQueueUrl);
	
	// subscribe our SQS queue to the SNS:s3MountTest topic
	SubscribeResult subscribeResult = snsClient.subscribe(snsTopicARN,"sqs",sqsQueueARN);
	snsSubscriptionARN = subscribeResult.getSubscriptionArn();
	logger.info("Subscribed for messages from SNS control channel:" + snsTopicARN + " ----> SQS: "+sqsQueueARN);
	logger.info("Subscription ARN: " + snsSubscriptionARN);
	
	this.consumerThread = new Thread(this,"ControlChannel msg consumer thread");
	this.consumerThread.start();

	logger.info("\n-------------------------------------------\n" +
				"CONTROL CHANNEL: ALL SNS/SQS resources hooked up OK\n" +
				"-------------------------------------------\n");
}