xml validity, ajax, and php

Question

Hello all. I'm returning some XML from PHP to Javascript via ajax and getting some 'invalid xml' errors. The xml I'm returning looks like this:

<response>
<song>tdb2009-01-29s2s06</song>
<song>tdb2009-01-29s1s02</song>
</response>

And my javascript to parse it looks like:

 function u_handleServerResponse(){  
   //pull xml from xml response  
   var xmlResponse = xmlHttp.responseXML;

   //check to see if xml was pulled
   if(!xmlResponse || !xmlResponse.documentElement){
     throw("Invalid XML Structure:\n" + xmlHttp.responseText);
   }

   //this is for catching errors with firefox
   var rootNodeName = xmlResponse.documentElement.nodeName;

   //check for errors
   if(rootNodeName == "parsererror"){
     throw("Invalid XML Strucutre");
   }

   //get the root
   xmlRoot = xmlResponse.documentElement;

   var songArray = xmlRoot.getElementsByTagName("song");

  for(var i = 0; i < songArray.length; i++){   
   etc., etc...

And I'm getting a

Error reading the response: Invalid XML Strucutre

error. Does all this look right to you? Is the xml wrong or is it being loaded wrong? All help is greatly appreciated. Thanks in advance...

Answer 1

You may need to include an xml header...

<?xml version="1.0" ?>

Answer 2

In addition to the XML header pointed out by rikh, you may need to declare the Content-Type header as text/xml for the responseXML to be correctly populated.

Answer 3

Here's my php:

<?php

//turn on error reporting
ini_set('display_errors', 'On');
error_reporting(E_ALL | E_STRICT);
header('Content-Type: text/xml');

//pull variables
//need to do some error checking here
$username = ($_GET['username']);

//connect with database
$con = mysql_connect("localhost","***","");
if(!$con){
  die('Could not connect: ' . mysql_error());
}

mysql_select_db("musicneverstopped", $con);
//end connecting to database

//////////////////////////////////////////

//begin processing results
$result = mysql_query("SELECT * FROM user_fav_songs WHERE username = '$username'");

//error check
if(!$result){
  die(mysql_error());
}

//check if any results were returned
if(mysql_num_rows($result) > 0){

  //if so set up the xml
  $dom = new DOMDocument();
  $response = $dom->createElement('response');
  $dom->appendChild($response);

  while($row = mysql_fetch_array($result)){

    //create song node    
    $song = $dom->createElement('song');
    $idText = $dom->createTextNode($row['unique_song_id']);
    $song->appendChild($idText);
    $response->appendChild($song);
  }//end while

  //save and echo xml
  $xmlString = $dom->saveXML(); 
  echo $xmlString;
}//end if

//////////////////////////////////////////

//close database connection
mysql_close($con);//close mysql connection


?>

Does that look right?

Answer 4

If you still have problems take a look at this article:
http://articles.techrepublic.com.com/5100-10878_11-6141415.html

Regards,
Bruno