Javascript Porter Ver 1.0 Source Code

/**
 * Javascript Porter ver 1.0
 * This program gathers and sends multiple Javascript files on demand
 * which benefits webpage loading speed in the way of avoiding
 * unnecessary requests and reduces the amount of Script tags on pages
 *
 * Instruction:
 * This program search under the preset folder (JSFILEFOLDER) for requested files and send them in order
 * This program accepts 3 arguments: l(link list), duplicate and compress
 * Arguments:
 *     link list
 *         A list of names of Javascript files needed to be gathered
 *         Do not include file extension (.js), separate with commas
 *     duplicate
 *         Allow duplication or not (i.e. when the request is "A,B,A", if duplication is not allowed, the last duplicated A will be ignored)
 *         Acceptable Value: true | yes | false | no
 *         Default: no
 *     compress
 *         Level of compression
 *         Add 1 to remove comment blocks
 *         Add 2 to remove comment lines
 *         Add 4 to remove indents
 *         Add 8 to remove line breakers
 *         i.e. if need to remove all comments, use value 3 (Add 1 and 2)
 *         Default: 0 (no compression)
 * Request Sample: js.php?l=jquery-latest,yui-latest&duplicate=true&compress=15
 * jquery-latest.js and yui-latest.js are requested, allowing duplication, at compression level of 15
 */
define('APPNAME', 'Javascript Porter ver 1.0');
define('JSFILEFOLDER', './js');
// Enable output buffer
	ob_start();
// Configure output header (Type: Javascript, Filename: container.js, disable cache)
	header('Content-Type: application/javascript');
	header('Content-Disposition: inline; filename="container.js"');
	header('Cache-Control: no-cache');
	header('Pragma: no-cache');
// Print program name
	printf("/* %s */n", APPNAME);
// Fetch raw request
// If link list is not found, halt the program
	if (!array_key_exists('l', $_GET))
		die('// no request');
	$rawRequestString = $_GET['l'];
	$allowDuplicate  = array_key_exists('duplicate', $_GET) 
							? (($_GET['duplicate'] == 'yes' || $_GET['duplicate'] == 'true')
								? true 
								: false) 
							: false;
	$compression      = array_key_exists('compress', $_GET) 
							? intval($_GET['compress']) 
							: 0;
// change to program directory
	chdir(dirname(__FILE__));
// check if Javascript file directory exists
if (!file_exists(JSFILEFOLDER) || !is_dir(JSFILEFOLDER))
	die('// js directory not found');
// change to Javascript file directory
	chdir(JSFILEFOLDER);
// Compression Function
function jsCompress($jsContent, $compressLevel)
{
	/**
	 * 1 Remove comment blocks
	 * 2 Remove comment lines
	 * 3 Remove all comments
	 * 4 Remove indents
	 * 5 Remove comment blocks + indents
	 * 6 Remove comment lines + indents
	 * 7 Remove all comments + indents
	 * 8 Remove line breakers *
	 * 9 Remove comment blocks + line breakers *
	 * 10 Remove comment lines + line breakers
	 * 11 Remove all comments + line breakers
	 * 12 Remove indents + line breakers *
	 * 13 Remove comment blocks + indents + line breakers *
	 * 14 Remove comment lines + indents + line breakers
	 * 15 Remove all comments + indents + line breakers
	 * * Not recommended before removing comment lines
	 */
	// return raw data if compression level is invalid
	if ($compressLevel > 15)
		return $jsContent;
	// remove comment blocks
	if ($compressLevel % 2 >= 1)
		$jsContent = preg_replace('//*.**//uUs', '', $jsContent);
	// remove comment lines
	if ($compressLevel % 4 >= 2)
		$jsContent = preg_replace('///.*$/uUm', '', $jsContent);
	// remove indents
	if ($compressLevel % 8 >= 4)
		$jsContent = preg_replace('/^s+/um', '', $jsContent);
	// remove line breakers
	if ($compressLevel % 16 >= 8)
		$jsContent = preg_replace('/(n|r)/um', '', $jsContent);
	return $jsContent;
}
// Print organized request info
	printf("// raw request: %sn", $rawRequestString);
	printf("// allow duplicates: %sn", $allowDuplicate ? 'true' : 'false');
// Turn request list into an array
	$requestList = explode(',', $rawRequestString);
// Traverse the requested items and generate a list of files to be loaded
// jsFiles this array has keys as Javascript filenames (without extension) and contents as Javascript file contents
	$jsFiles = Array();
// printList this array contains printing order
	$printList = Array();
	print("// requested js files: n");
	foreach ($requestList as $value) {
		$requestItem = trim(basename($value));
		if ($requestItem == '') continue;
		printf("// 	%s,n", $requestItem);
		if ($allowDuplicate || !array_key_exists($requestItem, $jsFiles))
			$printList[] = $requestItem;
		$jsFiles[$requestItem] = false;
	}
	print("// loading requested files:n");
	foreach ($jsFiles as $key => $value) {
		$filename = "{$key}.js";
		printf("// 	./%s ", $filename);
		if (file_exists($filename) && is_file($filename)) {
			$jsFiles[$key] = jsCompress(file_get_contents($filename), $compression);
			printf("(md5: %s)n", md5($jsFiles[$key]));
		} else {
			printf("%sn", 'not found');
		}
	}
// Print Javascript contents
	for ($i = 0; $i < count($printList); ++$i) {
		$key = $printList[$i];
		$content = $jsFiles[$key];
		printf("n// %sn%sn", $key, $content);
	}
// Program ends
	die();