iOS AWS SNS集成

Question

We are in the development of messaging application in the iPhone. The backend we are developing in Rails. And we are planning to upload the backend in AWS.

The features in our application are; • When a user sends a message (pictures, videos) to other users, we will keep the attachments in the Amazon S3 and keep the entry in the data base. • The backend should send a notification to the receivers and in the iPhone app the received notification should be shown. • When a user logs in to the iPhone application the other users needs to know the online/offline status of the users. • In the contact view of the application, users needs to know the online/offline status of the contacts (presence management)

We are planning to use Amazon SNS for sending notification from AWS backend to iPhone apps. Does the SNS supports presence management (online/offline status of the friends)? Can somebody point out any example for SNS iPhone application development?

Asking Sorry if I am asking too generic question.

Answer 1

For the intended use you are planning to make, both the SNS and the SQS do not have the necessary requirements, they do not have the selector feature, which if existed, could be used to filter the messages according to certain metadata, such as recipient or sender, similar to Java JMS, for more information on the term SELECTOR look javadoc javax.jms.Message .

In addition, there would also need a way to restrict user access based on metadata, currently permissions are based only on the operations available from the SNS and SQS individual queues, which is not granular enough.

So I think the ideal solution would be to implement the service in EC2, to coordinate the flow of all messages and online status, using a backend database for long term storage message storage, and optionally Elastic Cache to provide lower latency responses for messages and onine status.

In order to achieve better scaleability and reduce coupling, you should also consider using an internal SNS topic to postpone the update of the intermediate cache and the database.

It is also worth remembering that you can make use iPhone database as a local cache of messages available on the server.