Swift - JSON API

Api.swift

class API {
    
    let uri = "https://api.com/endpoint" // replace your api endpoint (json)
    
    func getData(completionHandler: ((NSArray!, NSError!) -> Void)!) -> Void {
        let url: NSURL = NSURL(string: uri)!
        
        let ses = NSURLSession.sharedSession()
        let task = ses.dataTaskWithURL(url, completionHandler: {data, response, error -> Void in
            
            if (error != nil) {
                return completionHandler(nil, error)
            }
            
            var error: NSError?
            let json = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &error) as NSDictionary
            
            if (error != nil) {
                return completionHandler(nil, error)
                
            } else {
                return completionHandler(json["results"] as [NSDictionary], nil)
            }
        })
        
        task.resume()
    }
}

TodayViewController.swift

var items: NSMutableArray = []
var api = API()

api.getData({data, error -> Void in
  if (data != nil) {
                
   dispatch_sync(dispatch_get_main_queue(), {
     self.items = NSMutableArray(array: data)
     self.tableView.reloadData()
     completionHandler(NCUpdateResult.NewData)
   })
                
   } else {
   completionHandler(NCUpdateResult.Failed)
   println(error)
  }
  
})