Blog

<?php

define('ABSPATH', dirname(__FILE__).'/');
$cache = true;

//Gzip压缩开关
$cachedir = 'gzip_cache/';

//存放gz文件的目录，使用前创建，并赋予可写权限
$gzip = strstr($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip');
$deflate = strstr($_SERVER['HTTP_ACCEPT_ENCODING'], 'deflate');
$encoding = $gzip ? 'gzip' : ($deflate ? 'deflate' : 'none');
if(!isset($_SERVER['QUERY_STRING'])) exit();
$key=array_shift(explode('?', $_SERVER['QUERY_STRING']));
$key=str_replace('../','',$key);
$filename=ABSPATH.$key;
$symbol='^';
$rel_path=str_replace(ABSPATH,'',dirname($filename));
$namespace=str_replace('/',$symbol,$rel_path);
$cache_filename=ABSPATH.$cachedir.$namespace.$symbol.basename($filename).'.gz';

//缓存路径
$type="Content-type: text/html";

//MIME信息
$ext = array_pop(explode('.', $filename));

//获取文件扩展名
switch ($ext) {
	//更新MIME信息
	case 'css':
	   $type="Content-type: text/css";
	break;
	case 'js':
	   $type="Content-type: text/javascript";
	break;
	default:
	   exit();
}
if($cache) {
	if(file_exists($cache_filename)) {
		//假如存在gz文件
		$mtime = filemtime($cache_filename);
		$gmt_mtime = gmdate('D, d M Y H:i:s', $mtime) . ' GMT';
		if( (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) &&
		            array_shift(explode(';', $_SERVER['HTTP_IF_MODIFIED_SINCE'])) ==  $gmt_mtime)
		       ) {
			// 若文件无变动，返回304
			header ("HTTP/1.1 304 Not Modified");
			header("Expires: ");
			header("Cache-Control: ");
			header("Pragma: ");
			header($type);
			header("Tips: Cache Not Modified (Gzip)");
			header ('Content-Length: 0');
		} else {
			//读取gz文件输出
			$content = file_get_contents($cache_filename);
			header("Last-Modified:" . $gmt_mtime);
			header("Expires: ");
			header("Cache-Control: ");
			header("Pragma: ");
			header($type);
			header("Tips: Normal Respond (Gzip)");
			header("Content-Encoding: gzip");
			echo $content;
		}
	} else if(file_exists($filename)) {
		//没有对应的gz文件
		$mtime = mktime();
		$gmt_mtime = gmdate('D, d M Y H:i:s', $mtime) . ' GMT';
		$content = file_get_contents($filename);
		$content = gzencode($content, 9, $gzip ? FORCE_GZIP : FORCE_DEFLATE);
		//压缩内容
		header("Last-Modified:" . $gmt_mtime);
		header("Expires: ");
		header("Cache-Control: ");
		header("Pragma: ");
		header($type);
		header("Tips: Build Gzip File (Gzip)");
		header ("Content-Encoding: " . $encoding);
		header ('Content-Length: ' . strlen($content));
		echo $content;
		if ($fp = fopen($cache_filename, 'w')) {
			//写入缓存
			fwrite($fp, $content);
			fclose($fp);
		}
	} else {
		header("HTTP/1.0 404 Not Found");
	}
} else {
	//关闭Gzip压缩
	if(file_exists($filename)) {
		$mtime = filemtime($filename);
		$gmt_mtime = gmdate('D, d M Y H:i:s', $mtime) . ' GMT';
		if( (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) &&
		      array_shift(explode(';', $_SERVER['HTTP_IF_MODIFIED_SINCE'])) ==  $gmt_mtime)
		      ) {
			header ("HTTP/1.1 304 Not Modified");
			header("Expires: ");
			header("Cache-Control: ");
			header("Pragma: ");
			header($type);
			header("Tips: Cache Not Modified");
			header ('Content-Length: 0');
		} else {
			header("Last-Modified:" . $gmt_mtime);
			header("Expires: ");
			header("Cache-Control: ");
			header("Pragma: ");
			header($type);
			header("Tips: Normal Respond");
			$content = readfile($filename);
			echo $content;
		}
	} else {
		header("HTTP/1.0 404 Not Found");
	}
}
?>

RewriteRule (.*.css$|.*.js$) /gzip.php\?$1 [L]