How to find problem with PHP XSLTProcessor when return from transformToXML is false and libxml_get_
- by John
I'm working on the code below to allow HTTP user agents that cannot perform XSL transformations to view the resources on my server. I'm mystified because the result of transformToXML is false, but the result of libxml_get_errors() is an empty array. As you can see, the code outputs the LibXSLT version ID and I'm getting the problem on WinVista with version 1.1.24. Is libxml_get_errors() not the right function to get the errors from the XSLTProcessor object?
If you're interested in the XML documents, you can get them from http://bobberinteractive.com/index.xhtml and .../stylesheets/layout.xsl
<?php
//redirect browsers that can handle the source files.
if (strpos ( $_SERVER ['HTTP_ACCEPT'], 'application/xhtml+xml' )) {
header ( "HTTP/1.1 301 Moved Permanently" );
header ( "Location: http://" . $_SERVER ['SERVER_NAME'] . "/index.xhtml" );
header ( "Content-Type: text/text" );
echo "\nYour browser is capable of processing the <a href='/index.xhtml' site contents on its own.";
die ();
}
//start by checking the template
$baseDir = dirname ( __FILE__ );
$xslDoc = new DOMDocument ();
if (! $xslDoc-load ( $baseDir . '/stylesheets/layout.xsl' )) {
header ( "HTTP/1.1 500 Server Error" );
header ( "Content-Type: text/plain" );
echo "\n Can't load " . $baseDir . '/stylesheets/layout.xsl';
die ();
}
//resolve the requested resource (browsers that need transformation will request the resource without the suffix)
$uri = $_SERVER ['REQUEST_URI'];
$len = strlen ( $uri );
if (1 = $len || '/' == substr ( $uri, $len - 1 )) {
$fileName = $baseDir . "/index.xhtml"; // use 'default' document if pathname ends in '/'
} else {
$fileName = $baseDir . (1 load ( $fileName )) {
header ( "HTTP/1.1 500 Server Error" );
echo "\n Can't load " . $fileName;
die ();
}
// now start the XSL template processing
$proc = new XSLTProcessor ();
$proc-importStylesheet ( $xslDoc );
$doc = $proc-transformToXML ( $xmlDoc );
if (false === $doc) {
header ( "HTTP/1.1 500 Server Error" );
header ( "Content-Type: text/plain" );
echo "\n";
// HERE is where it gets strange: the value of $doc is false and libxml_get_errors returns 0 entries.
display_xml_errors ( libxml_get_errors() );
die ();
}
header ( "Content-Type: text/html" );
echo "\n";
echo $doc;
function display_xml_errors($errors) {
echo count ( $errors ) . " Error(s) from LibXSLT " . LIBXSLT_DOTTED_VERSION;
for($i = 0; $i level) {
case LIBXML_ERR_WARNING :
$return .= "Warning $error-code: ";
break;
case LIBXML_ERR_ERROR :
$return .= "Error $error-code: ";
break;
case LIBXML_ERR_FATAL :
$return .= "Fatal Error $error-code: ";
break;
}
$return .= trim ( $error-message ) . "\n Line: $error-line" . "\n Column: $error-column";
if ($error-file) {
$return .= "\n File: $error-file";
}
echo "$return\n\n--------------------------------------------\n\n";
}
}
