title: How to get JSON response in jQuery.ajax request to an appengine URL?
body: <p>My URL service hosted at Google App Engine return JSON content type. </p>
  
  <p>The example URL is <a href="http://trim-pk.appspot.com/do?url=http://www.google.com" rel="nofollow noreferrer">this</a>, that works perfect in browser. Also validated from <a href="http://jsonlint.com" rel="nofollow noreferrer">http://jsonlint.com</a>.</p>
  
  <p>I am using following jQuery.ajax call to get the response. </p>
  
  <pre><code>jQuery.ajax({
  type: "get",
  url: "http://trim-pk.appspot.com/do?url=http://www.google.com",
  dataType: "json",
  success: function(response) {
      alert(response);
  } 
  });
  </code></pre>
  
  <p>What's went wrong? Why I am not getting the response. It's null. </p>
  
  <p>I have tried with <code>contentType: "application/json; charset=utf-8"</code> and <code>contentType: "application/json; charset=ISO-8859-1"</code>, but got 500. </p>
  
  <p>Following is my Firebug output. </p>
  
  <p><img src="https://i.stack.imgur.com/kVQEq.png" alt="enter image description here"></p>