XSLTransform

<?php
/******************************************************************************
Date:			Tue, 01 May 2001
Author:		 	Melvyn Sopacua
Description:	XSL Transformation using the 4.0.3+ API.
License:		GPL
Version:		1.4 (2001/05/05)
Comments:		Based on work done by Justin Grant @ phpbuilder.com.
Revisions:
	1.0		- Changed some function calls in Justin's files, for the new API.
	1.1		- Added CSV style logging in the error_handler.
	1.2		- Finally figured out how xslt_set_error_handler passes arguments.
	1.3		- Added 'XmlStrip' property and method to allow stripping of the
			  XML declaration at the start of the XSL transformation output,
			  so that files can be written as php includes.
	1.3.1	- Fixed resetting of the $errlog_opened variable
			- Added documentation about xsl:output method set to HTML
******************************************************************************/

/* 
	Usage example:
require('xsl_transform.class.php');
$xml_root="d:/server/xml-data";
$html_path=".";
$xml_file="$xml_root/wubba.xml";
$xsl_file="$xml_root/rsstest.xsl";
$html_file="$html_path/wubba.php";
$x=new XSLTransformer;
$ok=$x->setXml($xml_file);
if(!$ok)
{
	echo $x->getError();
	$x->destroy();
	exit;
}
$ok=$x->setXsl($xsl_file);
if(!$ok)
{
	echo $x->getError();
	$x->destroy();
	exit;
}	
$x->setXmlStrip();
$ok=$x->transform();
if(!$ok)
{
	echo $x->getError();
	$x->destroy();
	exit;
}
$html=$x->getOutput();
$x->destroy();
if(!($fp=fopen($html_file, "w")))
{
	$x->destroy();
	die("Error opening output file $html_file for writing. Check permissions.");
}
fwrite($fp, $html);
fclose($fp);
echo "OK";
*/



//___________________Since errors are trapped by reference we need this external
//_____________________________________________________________________function.

//___________Use variables if you're a change-it-all-around-all-the-time person.
//_________________You'll then need to globalize them in the xsl_error function.

define(XSL_ERR_LOG, "d:/server/logs/xslt_errors.log");
define(XSL_USE_ERR_LOG, 1);

set_time_limit(300);

$fp_errlog='';
$errlog_opened=0;

function xsl_error($errstr, $errno, $arr_msg)
{
	global $fp_errlog, $errlog_opened;
	if(!XSL_USE_ERR_LOG)
	{
		return true;
	}
	
	//_______________________________________________________We should log this.
	if(!$fp_errlog)
	{
		if(!$errlog_opened)
		{
			$fp_errlog=fopen(XSL_ERR_LOG, "a");
			$errlog_opened=1;
		}
		else
		{
			//__The only thing that comes to mind, is 1 not being equal to true.
			die("Error in logic or file-pointer conflicts.");
		}
	}
	//______At this point, returning false or true, does not make a difference,
	//_________at all, but since this is not expected behavior, this bit is made
	//________________________________________________to be forwards-compatible.
	//________One can argue, if a return false in this function, should generate
	//__________________________a php fatal error, since it is an error handler.
	//______On the other hand, one can argue, that the outcome of this function,
	//________________should determin the outcome of the transformation process.
	//____________At present the return value does neither, which is unexpected.
	if($arr_msg["msgtype"] != "error")
	{
		$line=sprintf(""%s","%s","%d","%s"n", date("d-m-Y H:i:s", time()), "warning", $arr_msg["line"], $arr_msg["msg"]);
		fwrite($fp_errlog, $line);
		return true;
	}
	else
	{
		$line=sprintf(""%s","%s","%d","%s"n", date("d-m-Y H:i:s", time()), "fatal", $arr_msg["line"], $arr_msg["msg"]);
		fwrite($fp_errlog, $line);
		return false;
	}
}


/*
	XSLTranformer -- Class to transform XML files using	
	XSL with the Sablotron libraries.Justin Grant (2000-07-30)
	Thanks to Bill Humphries for the original examples on	
	using the Sablotron module.
	Modified for new API by Melvyn Sopacua.
*/

class XSLTransformer
{
	var $xsl, $xml, $output, $error, $XmlStrip;

	function XSLTransformer()
	{
		$this->processor = xslt_create();
		$this->XmlStrip=false;
		xslt_set_error_handler("xsl_error");
	}
 /* Destructor */
	function destroy()
	{
		global $fp_errlog, $errlog_opened;
		
		//______________________________________Remember to close the error log!
		//____________________________________________And to reset the variable!
		if($errlog_opened)
		{
			fclose($fp_errlog);
			$errlog_opened=false;
		}
		xslt_free($this->processor);
	}
 /* output methods */
	function setOutput($string) 
	{
		$this->output = $string;
	}
	
	function getOutput() 
	{
		if($this->XmlStrip)
		{
			$this->output=ereg_replace("<?xml[^>]+>", "", $this->output);
		}
		return $this->output;
	}
 /* set methods */
	function setXml($uri) 
	{
		if($doc = new docReader($uri)) 
		{
			$this->xml = $doc->getString();
			return true;
		}
		else 
		{
			$this->setError("Could not open $xml");
			return false;
		}
	}
	function setXsl($uri) 
	{
		if($doc = new docReader($uri)) 
		{
			$this->xsl = $doc->getString();
			return true;
		}
		else 
		{
			$this->setError("Could not open $uri");
			return false;
		}
	}

	/*
		NOTE:
			the XmlStrip function provides a way to strip the XML declaration,
			so files written can be used as php includes, and php short-tags may
			still be used.
			Alternatively, you may use:
			<xsl:output omit-xml-declaration="yes"/>
			in your Xsl stylesheet. This however, would require two different,
			stylesheets for output as an xml file, or as a php include, while,
			the rest may be the same.
		
		NOTE 2:
			If you use processing instructions, like I do, to call PHP code,
			you cannot set the xsl output method to HTML.
			Setting the output method to HTML, will result in the closing tag
			for processing instructions to be '>' instead of '? >' (without the
			space). This will create parser errors in PHP.
			Example:
			<xsl:processing-instruction name="php">echo "This document: $REQ_URI";</xsl:processing-instruction>
	*/
	function setXmlStrip($boolean=true)
	{
		//__________Since the default is set to false, when calling this method, 
		//_______________________________people probably want to set it to true.
		$this->XmlStrip=$boolean;
	}
	
/* transform method */
	function transform() 
	{
		$return=@xslt_process($this->xsl, $this->xml, $outcome);
		$this->setOutput($outcome);
		return $return;
	}
/* Error Handling */
	//________________________________Does not handle the transformation errors.
	function setError($string) 
	{
		$this->error = $string;
	}
	function getError() 
	{
		return $this->error;
	}
}



/* docReader -- read a file or URL as a string */
/* test */
/*
	$docUri = new docReader('http://www.someurl.com/doc.html');
	echo $docUri->getString();
*/
class docReader {
	var $string; // public string representation of file
	var $type; // private URI type: 'file','url'
	var $bignum = 1000000;
 /* public constructor */
	function docReader($uri) { // returns integer
		$this->setUri($uri);
		$this->setType();
		$fp = fopen($this->getUri(),"r");
		if($fp)
		{ // get length
			if ($this->getType() == 'file')
			{
				$length = filesize($this->getUri());
			}
			else
			{
				$length = $this->bignum;
			}
				$this->setString(fread($fp,$length));
				return 1;
		}
		else 
		{
			return 0;
		}
	}
 /* determine if a URI is a filename or URL */
	function isFile($uri) { // returns boolean
		if (strstr($uri,'http://') == $uri) 
		{
			return false;
		}
		else 
		{
			return true;
		}
	}
 /* set and get methods */
	function setUri($string) 
	{
		$this->uri = $string;
	}
	function getUri() 
	{
		return $this->uri;
	}
	function setString($string) 
	{
		$this->string = $string;
	}
	function getString() 
	{
		return $this->string;
	}
	function setType() 
	{
		if ($this->isFile($this->uri)) 
		{
		 $this->type = 'file';
		}
		else 
		{
		 $this->type = 'url';
		}
	}
	function getType() 
	{
		return $this->type;
	}
}
?>