]> scripts.mit.edu Git - autoinstallsdev/mediawiki.git/blobdiff - includes/clientpool/SquidPurgeClient.php
MediaWiki 1.30.2
[autoinstallsdev/mediawiki.git] / includes / clientpool / SquidPurgeClient.php
diff --git a/includes/clientpool/SquidPurgeClient.php b/includes/clientpool/SquidPurgeClient.php
new file mode 100644 (file)
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--- /dev/null
@@ -0,0 +1,396 @@
+<?php
+/**
+ * Squid and Varnish cache purging.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ */
+
+/**
+ * An HTTP 1.0 client built for the purposes of purging Squid and Varnish.
+ * Uses asynchronous I/O, allowing purges to be done in a highly parallel
+ * manner.
+ *
+ * Could be replaced by curl_multi_exec() or some such.
+ */
+class SquidPurgeClient {
+       /** @var string */
+       protected $host;
+
+       /** @var int */
+       protected $port;
+
+       /** @var string|bool */
+       protected $ip;
+
+       /** @var string */
+       protected $readState = 'idle';
+
+       /** @var string */
+       protected $writeBuffer = '';
+
+       /** @var array */
+       protected $requests = [];
+
+       /** @var mixed */
+       protected $currentRequestIndex;
+
+       const EINTR = 4;
+       const EAGAIN = 11;
+       const EINPROGRESS = 115;
+       const BUFFER_SIZE = 8192;
+
+       /**
+        * @var resource|null The socket resource, or null for unconnected, or false
+        *   for disabled due to error.
+        */
+       protected $socket;
+
+       /** @var string */
+       protected $readBuffer;
+
+       /** @var int */
+       protected $bodyRemaining;
+
+       /**
+        * @param string $server
+        * @param array $options
+        */
+       public function __construct( $server, $options = [] ) {
+               $parts = explode( ':', $server, 2 );
+               $this->host = $parts[0];
+               $this->port = isset( $parts[1] ) ? $parts[1] : 80;
+       }
+
+       /**
+        * Open a socket if there isn't one open already, return it.
+        * Returns false on error.
+        *
+        * @return bool|resource
+        */
+       protected function getSocket() {
+               if ( $this->socket !== null ) {
+                       return $this->socket;
+               }
+
+               $ip = $this->getIP();
+               if ( !$ip ) {
+                       $this->log( "DNS error" );
+                       $this->markDown();
+                       return false;
+               }
+               $this->socket = socket_create( AF_INET, SOCK_STREAM, SOL_TCP );
+               socket_set_nonblock( $this->socket );
+               MediaWiki\suppressWarnings();
+               $ok = socket_connect( $this->socket, $ip, $this->port );
+               MediaWiki\restoreWarnings();
+               if ( !$ok ) {
+                       $error = socket_last_error( $this->socket );
+                       if ( $error !== self::EINPROGRESS ) {
+                               $this->log( "connection error: " . socket_strerror( $error ) );
+                               $this->markDown();
+                               return false;
+                       }
+               }
+
+               return $this->socket;
+       }
+
+       /**
+        * Get read socket array for select()
+        * @return array
+        */
+       public function getReadSocketsForSelect() {
+               if ( $this->readState == 'idle' ) {
+                       return [];
+               }
+               $socket = $this->getSocket();
+               if ( $socket === false ) {
+                       return [];
+               }
+               return [ $socket ];
+       }
+
+       /**
+        * Get write socket array for select()
+        * @return array
+        */
+       public function getWriteSocketsForSelect() {
+               if ( !strlen( $this->writeBuffer ) ) {
+                       return [];
+               }
+               $socket = $this->getSocket();
+               if ( $socket === false ) {
+                       return [];
+               }
+               return [ $socket ];
+       }
+
+       /**
+        * Get the host's IP address.
+        * Does not support IPv6 at present due to the lack of a convenient interface in PHP.
+        * @throws MWException
+        * @return string
+        */
+       protected function getIP() {
+               if ( $this->ip === null ) {
+                       if ( IP::isIPv4( $this->host ) ) {
+                               $this->ip = $this->host;
+                       } elseif ( IP::isIPv6( $this->host ) ) {
+                               throw new MWException( '$wgSquidServers does not support IPv6' );
+                       } else {
+                               MediaWiki\suppressWarnings();
+                               $this->ip = gethostbyname( $this->host );
+                               if ( $this->ip === $this->host ) {
+                                       $this->ip = false;
+                               }
+                               MediaWiki\restoreWarnings();
+                       }
+               }
+               return $this->ip;
+       }
+
+       /**
+        * Close the socket and ignore any future purge requests.
+        * This is called if there is a protocol error.
+        */
+       protected function markDown() {
+               $this->close();
+               $this->socket = false;
+       }
+
+       /**
+        * Close the socket but allow it to be reopened for future purge requests
+        */
+       public function close() {
+               if ( $this->socket ) {
+                       MediaWiki\suppressWarnings();
+                       socket_set_block( $this->socket );
+                       socket_shutdown( $this->socket );
+                       socket_close( $this->socket );
+                       MediaWiki\restoreWarnings();
+               }
+               $this->socket = null;
+               $this->readBuffer = '';
+               // Write buffer is kept since it may contain a request for the next socket
+       }
+
+       /**
+        * Queue a purge operation
+        *
+        * @param string $url
+        */
+       public function queuePurge( $url ) {
+               global $wgSquidPurgeUseHostHeader;
+               $url = CdnCacheUpdate::expand( str_replace( "\n", '', $url ) );
+               $request = [];
+               if ( $wgSquidPurgeUseHostHeader ) {
+                       $url = wfParseUrl( $url );
+                       $host = $url['host'];
+                       if ( isset( $url['port'] ) && strlen( $url['port'] ) > 0 ) {
+                               $host .= ":" . $url['port'];
+                       }
+                       $path = $url['path'];
+                       if ( isset( $url['query'] ) && is_string( $url['query'] ) ) {
+                               $path = wfAppendQuery( $path, $url['query'] );
+                       }
+                       $request[] = "PURGE $path HTTP/1.1";
+                       $request[] = "Host: $host";
+               } else {
+                       $request[] = "PURGE $url HTTP/1.0";
+               }
+               $request[] = "Connection: Keep-Alive";
+               $request[] = "Proxy-Connection: Keep-Alive";
+               $request[] = "User-Agent: " . Http::userAgent() . ' ' . __CLASS__;
+               // Two ''s to create \r\n\r\n
+               $request[] = '';
+               $request[] = '';
+
+               $this->requests[] = implode( "\r\n", $request );
+               if ( $this->currentRequestIndex === null ) {
+                       $this->nextRequest();
+               }
+       }
+
+       /**
+        * @return bool
+        */
+       public function isIdle() {
+               return strlen( $this->writeBuffer ) == 0 && $this->readState == 'idle';
+       }
+
+       /**
+        * Perform pending writes. Call this when socket_select() indicates that writing will not block.
+        */
+       public function doWrites() {
+               if ( !strlen( $this->writeBuffer ) ) {
+                       return;
+               }
+               $socket = $this->getSocket();
+               if ( !$socket ) {
+                       return;
+               }
+
+               if ( strlen( $this->writeBuffer ) <= self::BUFFER_SIZE ) {
+                       $buf = $this->writeBuffer;
+                       $flags = MSG_EOR;
+               } else {
+                       $buf = substr( $this->writeBuffer, 0, self::BUFFER_SIZE );
+                       $flags = 0;
+               }
+               MediaWiki\suppressWarnings();
+               $bytesSent = socket_send( $socket, $buf, strlen( $buf ), $flags );
+               MediaWiki\restoreWarnings();
+
+               if ( $bytesSent === false ) {
+                       $error = socket_last_error( $socket );
+                       if ( $error != self::EAGAIN && $error != self::EINTR ) {
+                               $this->log( 'write error: ' . socket_strerror( $error ) );
+                               $this->markDown();
+                       }
+                       return;
+               }
+
+               $this->writeBuffer = substr( $this->writeBuffer, $bytesSent );
+       }
+
+       /**
+        * Read some data. Call this when socket_select() indicates that the read buffer is non-empty.
+        */
+       public function doReads() {
+               $socket = $this->getSocket();
+               if ( !$socket ) {
+                       return;
+               }
+
+               $buf = '';
+               MediaWiki\suppressWarnings();
+               $bytesRead = socket_recv( $socket, $buf, self::BUFFER_SIZE, 0 );
+               MediaWiki\restoreWarnings();
+               if ( $bytesRead === false ) {
+                       $error = socket_last_error( $socket );
+                       if ( $error != self::EAGAIN && $error != self::EINTR ) {
+                               $this->log( 'read error: ' . socket_strerror( $error ) );
+                               $this->markDown();
+                               return;
+                       }
+               } elseif ( $bytesRead === 0 ) {
+                       // Assume EOF
+                       $this->close();
+                       return;
+               }
+
+               $this->readBuffer .= $buf;
+               while ( $this->socket && $this->processReadBuffer() === 'continue' );
+       }
+
+       /**
+        * @throws MWException
+        * @return string
+        */
+       protected function processReadBuffer() {
+               switch ( $this->readState ) {
+               case 'idle':
+                       return 'done';
+               case 'status':
+               case 'header':
+                       $lines = explode( "\r\n", $this->readBuffer, 2 );
+                       if ( count( $lines ) < 2 ) {
+                               return 'done';
+                       }
+                       if ( $this->readState == 'status' ) {
+                               $this->processStatusLine( $lines[0] );
+                       } else { // header
+                               $this->processHeaderLine( $lines[0] );
+                       }
+                       $this->readBuffer = $lines[1];
+                       return 'continue';
+               case 'body':
+                       if ( $this->bodyRemaining !== null ) {
+                               if ( $this->bodyRemaining > strlen( $this->readBuffer ) ) {
+                                       $this->bodyRemaining -= strlen( $this->readBuffer );
+                                       $this->readBuffer = '';
+                                       return 'done';
+                               } else {
+                                       $this->readBuffer = substr( $this->readBuffer, $this->bodyRemaining );
+                                       $this->bodyRemaining = 0;
+                                       $this->nextRequest();
+                                       return 'continue';
+                               }
+                       } else {
+                               // No content length, read all data to EOF
+                               $this->readBuffer = '';
+                               return 'done';
+                       }
+               default:
+                       throw new MWException( __METHOD__ . ': unexpected state' );
+               }
+       }
+
+       /**
+        * @param string $line
+        */
+       protected function processStatusLine( $line ) {
+               if ( !preg_match( '!^HTTP/(\d+)\.(\d+) (\d{3}) (.*)$!', $line, $m ) ) {
+                       $this->log( 'invalid status line' );
+                       $this->markDown();
+                       return;
+               }
+               list( , , , $status, $reason ) = $m;
+               $status = intval( $status );
+               if ( $status !== 200 && $status !== 404 ) {
+                       $this->log( "unexpected status code: $status $reason" );
+                       $this->markDown();
+                       return;
+               }
+               $this->readState = 'header';
+       }
+
+       /**
+        * @param string $line
+        */
+       protected function processHeaderLine( $line ) {
+               if ( preg_match( '/^Content-Length: (\d+)$/i', $line, $m ) ) {
+                       $this->bodyRemaining = intval( $m[1] );
+               } elseif ( $line === '' ) {
+                       $this->readState = 'body';
+               }
+       }
+
+       protected function nextRequest() {
+               if ( $this->currentRequestIndex !== null ) {
+                       unset( $this->requests[$this->currentRequestIndex] );
+               }
+               if ( count( $this->requests ) ) {
+                       $this->readState = 'status';
+                       $this->currentRequestIndex = key( $this->requests );
+                       $this->writeBuffer = $this->requests[$this->currentRequestIndex];
+               } else {
+                       $this->readState = 'idle';
+                       $this->currentRequestIndex = null;
+                       $this->writeBuffer = '';
+               }
+               $this->bodyRemaining = null;
+       }
+
+       /**
+        * @param string $msg
+        */
+       protected function log( $msg ) {
+               wfDebugLog( 'squid', __CLASS__ . " ($this->host): $msg" );
+       }
+}