How do I serialize DOM into XML using PHP?

Question

I am attempting to send html data in a question form from my php web application to mechanical turk so a user can see the entire html document from an email to work with. I have had difficulty thus far. In the thread linked below, I attempted to parse the html data using html5-lib.php, but I think I'm still missing a step in order to complete this.

Here's the current error I'm receiving:

Catchable fatal error: Object of class DOMNodeList could not be converted to string in urlgoeshere.php on line 35

Here's the current code I'm working with...

$thequestion = '<a href="linkgoeshere" target="_blank">click here</a>';


$thequestion = HTML5_Parser::parseFragment($thequestion);

var_dump($thequestion);
echo $thequestion;
//htmlspecialchars($thequestion);

$QuestionXML = '<QuestionForm xmlns="http://mechanicalturk.amazonaws.com/AWSMechanicalTurkDataSchemas/2005-10-01/QuestionForm.xsd">
  <Question>
    <QuestionContent>
      <Text>'.$thequestion.'</Text> //<--- Line35
    </QuestionContent>
    <AnswerSpecification>
      <FreeTextAnswer/>
    </AnswerSpecification>
  </Question>
</QuestionForm> ';

I'm not 100% sure if the parser is what I need to do in order to have this sent correctly - All I want to do is send html through this xml type document - I'm surprised it's been this difficult thus far.

This is somewhat of a continuation of another thread - What PHP code will help me parse html data in an xml form?

Answer 1

Take a look at DOMDocument for working with DOM/xml in PHP. If you want to embed HTML in your XML, use CDATA sections like this:

$QuestionXML = '<QuestionForm xmlns="http://mechanicalturk.amazonaws.com/AWSMechanicalTurkDataSchemas/2005-10-01/QuestionForm.xsd">
  <Question>
    <QuestionContent>
      <Text><![CDATA['.$thequestion.']]></Text>
    </QuestionContent>
    <AnswerSpecification>
      <FreeTextAnswer/>
    </AnswerSpecification>
  </Question>
</QuestionForm> ';

Answer 2

Not sure exactly what you're after. This is how i would create the XML needed to be transferred. Please let me know if i misunderstood the question

It also seems that you are missing the QuestionIdentifier node which is mandatory according to the .xsd file.

<?
$dom = new DOMDocument('1.0','UTF-8');
$dom->formatOutput = true;
$QuestionForm = $dom->createElement('QuestionForm');
$QuestionForm->setAttribute('xmlns','http://mechanicalturk.amazonaws.com/AWSMechanicalTurkDataSchemas/2005-10-01/QuestionForm.xsd');

// could loop this part for all the questions of the XML

$thequestion = '<a href="linkgoeshere" target="_blank">click here</a>';

//Not sure what this is supposed to be, but its required. Check the specs of the app for it. 
$questionID = "";

$Question = $dom->createElement('Question');

$QuestionIdentifier = $dom->createElement('QuestionIdentifier',$questionID);

$QuestionContent = $dom->createElement('QuestionContent');
$QuestionContent->appendChild($dom->createElement('Text',$thequestion));

$AnswerSpecification = $dom->createElement('AnswerSpecification');
$AnswerSpecification->appendChild($dom->createElement('FreeTextAnswer'));

$Question->appendChild($QuestionIdentifier);
$Question->appendChild($QuestionContent);
$Question->appendChild($AnswerSpecification);
$QuestionForm->appendChild($Question);
// End loop

$dom->appendChild($QuestionForm);

$xmlString = $dom->saveXML();

print($xmlString);
?>