www.gusucode.com > Piwik 网站流量统计系统 v2.9.1PHP源码程序 > Piwik 网站流量统计系统 v2.9.1/How to install Piwik.html/piwik/core/ProxyHttp.php
<?php
/**
* Piwik - free/libre analytics platform
*
* @link http://piwik.org
* @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
*
*/
namespace Piwik;
/**
* Http helper: static file server proxy, with compression, caching, isHttps() helper...
*
* Used to server piwik.js and the merged+minified CSS and JS files
*
*/
class ProxyHttp
{
const DEFLATE_ENCODING_REGEX = '/(?:^|, ?)(deflate)(?:,|$)/';
const GZIP_ENCODING_REGEX = '/(?:^|, ?)((x-)?gzip)(?:,|$)/';
/**
* Returns true if the current request appears to be a secure HTTPS connection
*
* @return bool
*/
public static function isHttps()
{
return Url::getCurrentScheme() === 'https';
}
/**
* Serve static files through php proxy.
*
* It performs the following actions:
* - Checks the file is readable or returns "HTTP/1.0 404 Not Found"
* - Returns "HTTP/1.1 304 Not Modified" after comparing the HTTP_IF_MODIFIED_SINCE
* with the modification date of the static file
* - Will try to compress the static file according to HTTP_ACCEPT_ENCODING. Compressed files are store in
* the /tmp directory. If compressing extensions are not available, a manually gzip compressed file
* can be provided in the /tmp directory. It has to bear the same name with an added .gz extension.
* Using manually compressed static files requires you to manually update the compressed file when
* the static file is updated.
* - Overrides server cache control config to allow caching
* - Sends Very Accept-Encoding to tell proxies to store different version of the static file according
* to users encoding capacities.
*
* Warning:
* Compressed filed are stored in the /tmp directory.
* If this method is used with two files bearing the same name but located in different locations,
* there is a risk of conflict. One file could be served with the content of the other.
* A future upgrade of this method would be to recreate the directory structure of the static file
* within a /tmp/compressed-static-files directory.
*
* @param string $file The location of the static file to serve
* @param string $contentType The content type of the static file.
* @param bool $expireFarFuture Day in the far future to set the Expires header to.
* Should be set to false for files that should not be cached.
* @param int|false $byteStart The starting byte in the file to serve. If false, the data from the beginning
* of the file will be served.
* @param int|false $byteEnd The ending byte in the file to serve. If false, the data from $byteStart to the
* end of the file will be served.
*/
public static function serverStaticFile($file, $contentType, $expireFarFutureDays = 100, $byteStart = false,
$byteEnd = false)
{
// if the file cannot be found return HTTP status code '404'
if (!file_exists($file)) {
Common::sendResponseCode(404);
return;
}
$modifiedSince = Http::getModifiedSinceHeader();
$fileModifiedTime = @filemtime($file);
$lastModified = gmdate('D, d M Y H:i:s', $fileModifiedTime) . ' GMT';
// set some HTTP response headers
self::overrideCacheControlHeaders('public');
Common::sendHeader('Vary: Accept-Encoding');
Common::sendHeader('Content-Disposition: inline; filename=' . basename($file));
if ($expireFarFutureDays) {
// Required by proxy caches potentially in between the browser and server to cache the request indeed
Common::sendHeader(self::getExpiresHeaderForFutureDay($expireFarFutureDays));
}
// Return 304 if the file has not modified since
if ($modifiedSince === $lastModified) {
Common::sendResponseCode(304);
return;
}
// if we have to serve the file, serve it now, either in the clear or compressed
if ($byteStart === false) {
$byteStart = 0;
}
if ($byteEnd === false) {
$byteEnd = filesize($file);
}
$compressed = false;
$encoding = '';
$compressedFileLocation = AssetManager::getInstance()->getAssetDirectory() . '/' . basename($file);
if (!($byteStart == 0
&& $byteEnd == filesize($file))
) {
$compressedFileLocation .= ".$byteStart.$byteEnd";
}
$phpOutputCompressionEnabled = self::isPhpOutputCompressed();
if (isset($_SERVER['HTTP_ACCEPT_ENCODING']) && !$phpOutputCompressionEnabled) {
list($encoding, $extension) = self::getCompressionEncodingAcceptedByClient();
$filegz = $compressedFileLocation . $extension;
if (self::canCompressInPhp()) {
if (!empty($encoding)) {
// compress the file if it doesn't exist or is newer than the existing cached file, and cache
// the compressed result
if (self::shouldCompressFile($file, $filegz)) {
self::compressFile($file, $filegz, $encoding, $byteStart, $byteEnd);
}
$compressed = true;
$file = $filegz;
$byteStart = 0;
$byteEnd = filesize($file);
}
} else {
// if a compressed file exists, the file was manually compressed so we just serve that
if ($extension == '.gz'
&& !self::shouldCompressFile($file, $filegz)
) {
$compressed = true;
$file = $filegz;
$byteStart = 0;
$byteEnd = filesize($file);
}
}
}
Common::sendHeader('Last-Modified: ' . $lastModified);
if (!$phpOutputCompressionEnabled) {
Common::sendHeader('Content-Length: ' . ($byteEnd - $byteStart));
}
if (!empty($contentType)) {
Common::sendHeader('Content-Type: ' . $contentType);
}
if ($compressed) {
Common::sendHeader('Content-Encoding: ' . $encoding);
}
if (!_readfile($file, $byteStart, $byteEnd)) {
Common::sendResponseCode(500);
}
}
/**
* Test if php output is compressed
*
* @return bool True if php output is (or suspected/likely) to be compressed
*/
public static function isPhpOutputCompressed()
{
// Off = ''; On = '1'; otherwise, it's a buffer size
$zlibOutputCompression = ini_get('zlib.output_compression');
// could be ob_gzhandler, ob_deflatehandler, etc
$outputHandler = ini_get('output_handler');
// output handlers can be stacked
$obHandlers = array_filter(ob_list_handlers(), function ($var) {
return $var !== "default output handler";
});
// user defined handler via wrapper
if (!defined('PIWIK_TEST_MODE')) {
$autoPrependFile = ini_get('auto_prepend_file');
$autoAppendFile = ini_get('auto_append_file');
}
return !empty($zlibOutputCompression) ||
!empty($outputHandler) ||
!empty($obHandlers) ||
!empty($autoPrependFile) ||
!empty($autoAppendFile);
}
/**
* Workaround IE bug when downloading certain document types over SSL and
* cache control headers are present, e.g.,
*
* Cache-Control: no-cache
* Cache-Control: no-store,max-age=0,must-revalidate
* Pragma: no-cache
*
* @see http://support.microsoft.com/kb/316431/
* @see RFC2616
*
* @param string $override One of "public", "private", "no-cache", or "no-store". (optional)
*/
public static function overrideCacheControlHeaders($override = null)
{
if ($override || self::isHttps()) {
Common::sendHeader('Pragma: ');
Common::sendHeader('Expires: ');
if (in_array($override, array('public', 'private', 'no-cache', 'no-store'))) {
Common::sendHeader("Cache-Control: $override, must-revalidate");
} else {
Common::sendHeader('Cache-Control: must-revalidate');
}
}
}
/**
* Returns a formatted Expires HTTP header for a certain number of days in the future. The result
* can be used in a call to `header()`.
*/
private static function getExpiresHeaderForFutureDay($expireFarFutureDays)
{
return "Expires: " . gmdate('D, d M Y H:i:s', time() + 86400 * (int)$expireFarFutureDays) . ' GMT';
}
private static function getCompressionEncodingAcceptedByClient()
{
$acceptEncoding = $_SERVER['HTTP_ACCEPT_ENCODING'];
if (preg_match(self::DEFLATE_ENCODING_REGEX, $acceptEncoding, $matches)) {
return array('deflate', '.deflate');
} else if (preg_match(self::GZIP_ENCODING_REGEX, $acceptEncoding, $matches)) {
return array('gzip', '.gz');
} else {
return array(false, false);
}
}
private static function canCompressInPhp()
{
return extension_loaded('zlib') && function_exists('file_get_contents') && function_exists('file_put_contents');
}
private static function shouldCompressFile($fileToCompress, $compressedFilePath)
{
$toCompressLastModified = @filemtime($fileToCompress);
$compressedLastModified = @filemtime($compressedFilePath);
return !file_exists($compressedFilePath) || ($toCompressLastModified > $compressedLastModified);
}
private static function compressFile($fileToCompress, $compressedFilePath, $compressionEncoding, $byteStart,
$byteEnd)
{
$data = file_get_contents($fileToCompress);
$data = substr($data, $byteStart, $byteEnd - $byteStart);
if ($compressionEncoding == 'deflate') {
$data = gzdeflate($data, 9);
} else if ($compressionEncoding == 'gzip' || $compressionEncoding == 'x-gzip') {
$data = gzencode($data, 9);
}
file_put_contents($compressedFilePath, $data);
}
}