title: Vala - How to create a HTTP request with Soup?
body: <p>I'm a bit lost with vala docs.
  Im trying to do a POST request to my AJAX service with soap lib, but no luck. Can anyone tell me what i'm doing wrong?</p>
  
  <pre><code>string url = "http://myservice/ajax.php";          
  
  // create an HTTP session
  var session = new Soup.Session ();
  var message = new Soup.Message ("POST", url);
  
  //Setting params and request
  var params = "action=call&amp;method=get_monuments";    
  Soup.MemoryUse buffer = Soup.MemoryUse.STATIC;  
  
  //(Error here - Line 73)
  message.set_request ("application/x-www-form-urlencoded", buffer, params, params.length);
  
  // send the HTTP request and wait for response
  session.send_message (message);
  stdout.write(message.response_body.data);
  </code></pre>
  
  <p>Compiler drops following error:</p>
  
  <pre><code>/home/ibsenleo/valaprojects/test/main.vala(73,73): Error: Argument 3: Cannot convert from `string' to `uint8[]'
  </code></pre>
  
  <p>I'm sure is something about request parameters and the data type, but i couldn't find some useful examples.</p>