Compress image unto 1 mb in swift

extension UIImageView{
    func cacheImage(urlString: String){
         if let url = URL(string: urlString.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)!)
         {
        image = nil
        
        if let imageFromCache = imageCache.object(forKey: urlString as AnyObject) as? UIImage {
            self.image = imageFromCache
            return
        }
       //imageView.startShimmering()
            URLSession.shared.dataTask(with: url) {
            data, response, error in
                if error != nil
                {
                DispatchQueue.main.async {
                 //imageView.stopShimmering()
                 self.image = nil
                    }
                }
                if let _ = data {
                DispatchQueue.main.async {
                    guard let imageToCache = UIImage(data: data!) else { return }
                    var compressionPercentage = 1.0
                    //if data is greater then 1mb then compress it and decrease size to 1 mb
                    if (data?.count ?? 0) > 1048576{
                        compressionPercentage = 1048576.0 / Double(data?.count ?? 1)
                    }
                    let compressedData = UIImageJPEGRepresentation(imageToCache, CGFloat(compressionPercentage))
                    guard let compressedimageToCache = UIImage(data: compressedData!) else { return }
                    imageCache.setObject(compressedimageToCache, forKey: urlString as AnyObject)
                    self.image = compressedimageToCache
                    //imageView.stopShimmering()
                }
            }
            }.resume()
        }
        
    }
}