func diskImageDownloader(diskSpaceMB: Int = 100) -> ImageDownloader {

    let diskCapacity = diskSpaceMB * 1024 * 1024
    let diskCache = NSURLCache(memoryCapacity: 0, diskCapacity: diskCapacity, diskPath: "alamofireimage_disk_cache")
    let configuration = NSURLSessionConfiguration.defaultSessionConfiguration()
    configuration.URLCache = diskCache
    let downloader = ImageDownloader(configuration: configuration)
    UIImageView.af_sharedImageDownloader = downloader

    return downloader
}

func getProfileImage(atURL url: String, onComplete: SRServiceResponse<UIImage> -> Void) {
    guard let imageURL = NSURL(string: url) else
    {
        // TODO: Fail here
        return
    }

    let request = NSURLRequest(URL: imageURL)

    let imageDownloader = self.diskImageDownloader()

    imageDownloader.downloadImage(URLRequest: request) { (response) in
        switch response.result
        {
        case .Success(let image):
            // Do something
        case .Failure(let error):
            // Do something
        }
    }
}