关于wordpress的优化

define(‘ABSPATH’, dirname(__FILE__).’/');

$cache = true;//Gzip压缩开关
$cachedir = ‘wp-cache/’;//存放gz文件的目录，确保可写

$gzip = strstr($_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’;//生成gz文件路径

$type=”Content-type: text/html”; //默认的类型信息

$ext = array_pop(explode(‘.’, $filename));//根据后缀判断文件类型信息
switch ($ext){
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)
){

// 浏览器cache中的文件修改日期是否一致，将返回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);//读取文件
$content = gzencode($content, 9, $gzip ? FORCE_GZIP : FORCE_DEFLATE);//压缩文件内容

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gz文件，供下次使用
fwrite($fp, $content);
fclose($fp);
}

}else{
header(“HTTP/1.0 404 Not Found”);
}
}else{ //处理不使用Gzip模式下的输出。原理基本同上
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”);
}
}

?>

if(file_exists($filename) && time() < filemtime($filename) + $cache_time ){

$handle = fopen($filename, “r”);
$contents = fread($handle, filesize ($filename));
fclose($handle);
return $contents;

}else{

$contents = call_user_func_array($function,$args_array);

if($contents){
if (!$handle = fopen($filename, ‘w’)) {
echo “不能打开文件 $filename”;
exit();
}
if (!fwrite($handle, $contents)) {
echo “不能写入到文件 $filename”;
exit();
}
fclose($handle);
}
return $contents;
}
}