summaryrefslogtreecommitdiff
path: root/includes/objectcache/EhcacheBagOStuff.php
blob: 75aad27acb9b75c32aa1d1bdbdcdd2a6c8eb085e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
<?php

/**
 * Client for the Ehcache RESTful web service - http://ehcache.org/documentation/cache_server.html
 * TODO: Simplify configuration and add to the installer.
 */
class EhcacheBagOStuff extends BagOStuff {
	var $servers, $cacheName, $connectTimeout, $timeout, $curlOptions, 
		$requestData, $requestDataPos;
	
	var $curls = array();

	function __construct( $params ) {
		if ( !defined( 'CURLOPT_TIMEOUT_MS' ) ) {
			throw new MWException( __CLASS__.' requires curl version 7.16.2 or later.' );
		}
		if ( !extension_loaded( 'zlib' ) ) {
			throw new MWException( __CLASS__.' requires the zlib extension' );
		}
		if ( !isset( $params['servers'] ) ) {
			throw new MWException( __METHOD__.': servers parameter is required' );
		}
		$this->servers = $params['servers'];
		$this->cacheName = isset( $params['cache'] ) ? $params['cache'] : 'mw';
		$this->connectTimeout = isset( $params['connectTimeout'] ) 
			? $params['connectTimeout'] : 1;
		$this->timeout = isset( $params['timeout'] ) ? $params['timeout'] : 1;
		$this->curlOptions = array(
			CURLOPT_CONNECTTIMEOUT_MS => intval( $this->connectTimeout * 1000 ),
			CURLOPT_TIMEOUT_MS => intval( $this->timeout * 1000 ),
			CURLOPT_RETURNTRANSFER => 1,
			CURLOPT_CUSTOMREQUEST => 'GET',
			CURLOPT_POST => 0,
			CURLOPT_POSTFIELDS => '',
			CURLOPT_HTTPHEADER => array(),
		);
	}

	public function get( $key ) {
		wfProfileIn( __METHOD__ );
		$response = $this->doItemRequest( $key );
		if ( !$response || $response['http_code'] == 404 ) {
			wfProfileOut( __METHOD__ );
			return false;
		}
		if ( $response['http_code'] >= 300 ) {
			wfDebug( __METHOD__.": GET failure, got HTTP {$response['http_code']}\n" );
			wfProfileOut( __METHOD__ );
			return false;			
		}
		$body = $response['body'];
		$type = $response['content_type'];
		if ( $type == 'application/vnd.php.serialized+deflate' ) {
			$body = gzinflate( $body );
			if ( !$body ) {
				wfDebug( __METHOD__.": error inflating $key\n" );
				wfProfileOut( __METHOD__ );
				return false;
			}
			$data = unserialize( $body );
		} elseif ( $type == 'application/vnd.php.serialized' ) {
			$data = unserialize( $body );
		} else {
			wfDebug( __METHOD__.": unknown content type \"$type\"\n" );
			wfProfileOut( __METHOD__ );
			return false;
		}

		wfProfileOut( __METHOD__ );
		return $data;
	}

	public function set( $key, $value, $expiry = 0 ) {
		wfProfileIn( __METHOD__ );
		$expiry = $this->convertExpiry( $expiry );
		$ttl = $expiry ? $expiry - time() : 2147483647;
		$blob = serialize( $value );
		if ( strlen( $blob ) > 100 ) {
			$blob = gzdeflate( $blob );
			$contentType = 'application/vnd.php.serialized+deflate';
		} else {
			$contentType = 'application/vnd.php.serialized';
		}

		$code = $this->attemptPut( $key, $blob, $contentType, $ttl );

		if ( $code == 404 ) {
			// Maybe the cache does not exist yet, let's try creating it
			if ( !$this->createCache( $key ) ) {
				wfDebug( __METHOD__.": cache creation failed\n" );
				wfProfileOut( __METHOD__ );
				return false;
			}
			$code = $this->attemptPut( $key, $blob, $contentType, $ttl );
		}

		$result = false;
		if ( !$code ) {
			wfDebug( __METHOD__.": PUT failure for key $key\n" );
		} elseif ( $code >= 300 ) {
			wfDebug( __METHOD__.": PUT failure for key $key: HTTP $code\n" );
		} else {
			$result = true;
		}

		wfProfileOut( __METHOD__ );
		return $result;
	}

	public function delete( $key, $time = 0 ) {
		wfProfileIn( __METHOD__ );
		$response = $this->doItemRequest( $key,
			array( CURLOPT_CUSTOMREQUEST => 'DELETE' ) );
		$code = isset( $response['http_code'] ) ? $response['http_code'] : 0;
		if ( !$response || ( $code != 404 && $code >= 300 ) ) {
			wfDebug( __METHOD__.": DELETE failure for key $key\n" );
			$result = false;
		} else {
			$result = true;
		}
		wfProfileOut( __METHOD__ );
		return $result;
	}

	protected function getCacheUrl( $key ) {
		if ( count( $this->servers ) == 1 ) {
			$server = reset( $this->servers );
		} else {
			// Use consistent hashing
			$hashes = array();
			foreach ( $this->servers as $server ) {
				$hashes[$server] = md5( $server . '/' . $key );
			}
			asort( $hashes );
			reset( $hashes );
			$server = key( $hashes );
		}
		return "http://$server/ehcache/rest/{$this->cacheName}";
	}

	/**
	 * Get a cURL handle for the given cache URL.
	 * We cache the handles to allow keepalive.
	 */
	protected function getCurl( $cacheUrl ) {
		if ( !isset( $this->curls[$cacheUrl] ) ) {
			$this->curls[$cacheUrl] = curl_init();
		}
		return $this->curls[$cacheUrl];
	}

	protected function attemptPut( $key, $data, $type, $ttl ) {
		// In initial benchmarking, it was 30 times faster to use CURLOPT_POST 
		// than CURLOPT_UPLOAD with CURLOPT_READFUNCTION. This was because
		// CURLOPT_UPLOAD was pushing the request headers first, then waiting 
		// for an ACK packet, then sending the data, whereas CURLOPT_POST just
		// sends the headers and the data in a single send().
		$response = $this->doItemRequest( $key,
			array(
				CURLOPT_POST => 1,
				CURLOPT_CUSTOMREQUEST => 'PUT',
				CURLOPT_POSTFIELDS => $data,
				CURLOPT_HTTPHEADER => array(
					'Content-Type: ' . $type,
					'ehcacheTimeToLiveSeconds: ' . $ttl
				)
			)
		);
		if ( !$response ) {
			return 0;
		} else {
			return $response['http_code'];
		}
	}

	protected function createCache( $key ) {
		wfDebug( __METHOD__.": creating cache for $key\n" );
		$response = $this->doCacheRequest( $key, 
			array(
				CURLOPT_POST => 1,
				CURLOPT_CUSTOMREQUEST => 'PUT',
				CURLOPT_POSTFIELDS => '',
			) );
		if ( !$response ) {
			wfDebug( __CLASS__.": failed to create cache for $key\n" );
			return false;
		}
		if ( $response['http_code'] == 201 /* created */ 
			|| $response['http_code'] == 409 /* already there */ ) 
		{
			return true;
		} else {
			return false;
		}			
	}

	protected function doCacheRequest( $key, $curlOptions = array() ) {
		$cacheUrl = $this->getCacheUrl( $key );
		$curl = $this->getCurl( $cacheUrl );
		return $this->doRequest( $curl, $cacheUrl, $curlOptions );
	}

	protected function doItemRequest( $key, $curlOptions = array() ) {
		$cacheUrl = $this->getCacheUrl( $key );
		$curl = $this->getCurl( $cacheUrl );
		$url = $cacheUrl . '/' . rawurlencode( $key );
		return $this->doRequest( $curl, $url, $curlOptions );
	}

	protected function doRequest( $curl, $url, $curlOptions = array() ) {
		if ( array_diff_key( $curlOptions, $this->curlOptions ) ) {
			// var_dump( array_diff_key( $curlOptions, $this->curlOptions ) );
			throw new MWException( __METHOD__.": to prevent options set in one doRequest() " .
				"call from affecting subsequent doRequest() calls, only options listed " . 
				"in \$this->curlOptions may be specified in the \$curlOptions parameter." );
		}
		$curlOptions += $this->curlOptions;
		$curlOptions[CURLOPT_URL] = $url;

		curl_setopt_array( $curl, $curlOptions );
		$result = curl_exec( $curl );
		if ( $result === false ) {
			wfDebug( __CLASS__.": curl error: " . curl_error( $curl ) . "\n" );
			return false;
		}
		$info = curl_getinfo( $curl );
		$info['body'] = $result;
		return $info;
	}
}