use Concrete\Core\Support\Facade\Application;
   function getImgViaURL($this_url) {
      $app = Application::getFacadeApplication();
      $cf = $app->make('helper/file');
      $file = $app->make('helper/file');
      $fp = FilePermissions::getGlobal();
      $valt = $app->make('helper/validation/token');
      $app->make('helper/mime');
      $error = $app->make('helper/validation/error');
       // $this_url = trim($_REQUEST['url_upload_' .$i]);
 
      $client = $app->make('http/client');
      $request = $client->getRequest();
      $request->setUri($this_url);
      $response = $client->send();
      if ($response->isSuccess()) {
          $headers = $response->getHeaders();
          $contentType = $headers->get('ContentType')->getFieldValue();
          $fpath = $file->getTemporaryDirectory();//set a temp directory. NOT necessarily in content.
          //Make a random file name based on mimetype
          // figure out a filename based on filename, mimetype, ???
         if ($contentType) {
              // use mimetype from http response
              $fextension = $app->make('helper/mime')->mimeToExtension($contentType);
              if ($fextension === false) {
                  $error->add(t('Unknown mime-type: %s', h($contentType)));
              } else {
                  // make sure we're coming up with a unique filename
                  do {//make a random file
                      // make up a filename based on the current date/time, a random int, and the extension from the mime-type
                      $fname = date('Y-m-d_H-i_') . mt_rand(100, 999) . '.' . $fextension;
                  } while (file_exists($fpath.'/'.$fname)); //and keep trying if you find the file.
              }
          }
          if (strlen($fname)) {
                // write the downloaded file to a temporary location on disk
                $handle = fopen($fpath.'/'.$fname, "w");
                fwrite($handle, $response->getBody());
                fclose($handle);
            }
          $src = $fpath.'/'.$fname;
          return $src;
      }
   }
//Now import to concrete5 via file
   function importImgConcrete ($src, $fileName="tempImg") {
      $fileExtension = pathinfo($src)['extension'];
      $importer = new \Concrete\Core\File\Importer();
      $newFileVersion = $importer->import($src, "$fileName.$fileExtension");
      $newFile = $newFileVersion->getFile();
      $newFileID = $newFileVersion->getFileID();
      unlink($src);
      return array ($newFile, $newFileID);
   }
/*Access like this:*/
$url = "http://this.that.com/those.jpg";
$imageDownloaded = getImgViaURL($url);
$imageIntoConcrete = importImgConcrete($imageDownloaded, "name of file i want to keep");
//$imageIntoConcrete[0] is a file object from which you can create thumbnails
//$imageIntoConcrete[1] is the file object ID