Async image download swift

download-image.swift

var image: UIImage?
        var imageURL = "Some url"
        if let url = NSURL(string: imageURL) {
            let request: NSURLRequest = NSURLRequest(URL: url)
            let mainQueue = NSOperationQueue.mainQueue()
            NSURLConnection.sendAsynchronousRequest(request, queue: mainQueue, completionHandler: { (response, data, error) -> Void in
                if error == nil {
                    let image = UIImage(data: data)
                    dispatch_async(dispatch_get_main_queue(), {
                        // Update image
                    })
                }
                else {
                    println("Error: \(error.localizedDescription)")
                }
            })
        }