title: How to validate image from external source
body: <p>User can paste image url on form, then my app download this on local server. I would like validate this image, but i have problem.</p>
  <p>Input:</p>
  <pre><code>$image = &quot;http://example.com/image.png&quot;;
  </code></pre>
  <p>Rules, but not working</p>
  <pre><code>'image' =&gt; [
     'required', 
     'url', 
     'mimes:jpeg,png', 
     'max:5120', 
     'dimensions:min_width=400,min_height=400', 
     new FileExtensionRule(['png', 'jpg', 'jpeg'])
  ]
  </code></pre>
  <p>How can I validate image from external source.</p>