gistfile1.js

// Uses XMLHttpRequest to get a json object from a URI
function JSONHttpRequest(URI, onResponse, method_opt, charset_opt){
  var method = method_opt || 'GET';
  var charset = charset_opt || 'utf-8';
  
  var request = new XMLHttpRequest();
  request.open(method, URI, true);
  request.setRequestHeader("Content-Type", "application/json;charset=" + charset);
  
  request.onreadystatechange = function() {
    if (request.readyState == 4 && request.status == 200) {
      if (request.responseText) {
        console.log(JSON.parse(request.responseText)['body']);
        onResponse.call(JSON.parse(request.responseText)['body']);
      }
    }
  }
  
  request.send(null);
}