Adding Uploader Feature to Mac OSX App

I already have a cocoa mac OSX (works in background and has an icon in the status bar) and I need to add a new feature to it. Basically the app generates a stream of data that needs to be uploaded to the server. The backend is already done in C# and it’s basically a SOAP web service (a working example to connect to it will be provided written in Objective-C). There would be 2 kind of data to be uploaded: * JSON (text will be provided). * File (file path will be provided). - So the uploader class should have only 2 public methods (one for files and other for json) that should be called in the app in 2 different places. - The uploader should be multi-threaded (adjustable number of threads) in order to be able to upload multiple files asynchronously. - The uploader should maintain a queue of the current uploading tasks in order to restart its process once the app becomes online again or once the app reopened again or in case of a crash. - The uploader is responsible for storing the JSON (text) to the disk in a temporary folder till it’s uploaded successfully. That’s just to make sure the data won’t be lost once the server is down or once the app is offline. - The uploader should retry again to upload the data once connection is back. - The app icon in status bar should reflect the status (online/offline/uploading). - The key point is stability.