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
|
<?php
if( !defined( 'MEDIAWIKI' ) ) {
die( 1 );
}
/**
* @todo document
* @addtogroup Ajax
*/
class AjaxResponse {
var $mCacheDuration;
var $mVary;
var $mDisabled;
var $mText;
var $mResponseCode;
var $mLastModified;
var $mContentType;
function __construct( $text = NULL ) {
$this->mCacheDuration = NULL;
$this->mVary = NULL;
$this->mDisabled = false;
$this->mText = '';
$this->mResponseCode = '200 OK';
$this->mLastModified = false;
$this->mContentType= 'text/html; charset=utf-8';
if ( $text ) {
$this->addText( $text );
}
}
function setCacheDuration( $duration ) {
$this->mCacheDuration = $duration;
}
function setVary( $vary ) {
$this->mVary = $vary;
}
function setResponseCode( $code ) {
$this->mResponseCode = $code;
}
function setContentType( $type ) {
$this->mContentType = $type;
}
function disable() {
$this->mDisabled = true;
}
function addText( $text ) {
if ( ! $this->mDisabled && $text ) {
$this->mText .= $text;
}
}
function printText() {
if ( ! $this->mDisabled ) {
print $this->mText;
}
}
function sendHeaders() {
global $wgUseSquid, $wgUseESI;
if ( $this->mResponseCode ) {
$n = preg_replace( '/^ *(\d+)/', '\1', $this->mResponseCode );
header( "Status: " . $this->mResponseCode, true, (int)$n );
}
header ("Content-Type: " . $this->mContentType );
if ( $this->mLastModified ) {
header ("Last-Modified: " . $this->mLastModified );
}
else {
header ("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
}
if ( $this->mCacheDuration ) {
# If squid caches are configured, tell them to cache the response,
# and tell the client to always check with the squid. Otherwise,
# tell the client to use a cached copy, without a way to purge it.
if( $wgUseSquid ) {
# Expect explicite purge of the proxy cache, but require end user agents
# to revalidate against the proxy on each visit.
# Surrogate-Control controls our Squid, Cache-Control downstream caches
if ( $wgUseESI ) {
header( 'Surrogate-Control: max-age='.$this->mCacheDuration.', content="ESI/1.0"');
header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
} else {
header( 'Cache-Control: s-maxage='.$this->mCacheDuration.', must-revalidate, max-age=0' );
}
} else {
# Let the client do the caching. Cache is not purged.
header ("Expires: " . gmdate( "D, d M Y H:i:s", time() + $this->mCacheDuration ) . " GMT");
header ("Cache-Control: s-max-age={$this->mCacheDuration},public,max-age={$this->mCacheDuration}");
}
} else {
# always expired, always modified
header ("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); // Date in the past
header ("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
header ("Pragma: no-cache"); // HTTP/1.0
}
if ( $this->mVary ) {
header ( "Vary: " . $this->mVary );
}
}
/**
* checkLastModified tells the client to use the client-cached response if
* possible. If sucessful, the AjaxResponse is disabled so that
* any future call to AjaxResponse::printText() have no effect. The method
* returns true iff the response code was set to 304 Not Modified.
*/
function checkLastModified ( $timestamp ) {
global $wgCachePages, $wgCacheEpoch, $wgUser;
$fname = 'AjaxResponse::checkLastModified';
if ( !$timestamp || $timestamp == '19700101000000' ) {
wfDebug( "$fname: CACHE DISABLED, NO TIMESTAMP\n" );
return;
}
if( !$wgCachePages ) {
wfDebug( "$fname: CACHE DISABLED\n", false );
return;
}
if( $wgUser->getOption( 'nocache' ) ) {
wfDebug( "$fname: USER DISABLED CACHE\n", false );
return;
}
$timestamp = wfTimestamp( TS_MW, $timestamp );
$lastmod = wfTimestamp( TS_RFC2822, max( $timestamp, $wgUser->mTouched, $wgCacheEpoch ) );
if( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
# IE sends sizes after the date like this:
# Wed, 20 Aug 2003 06:51:19 GMT; length=5202
# this breaks strtotime().
$modsince = preg_replace( '/;.*$/', '', $_SERVER["HTTP_IF_MODIFIED_SINCE"] );
$modsinceTime = strtotime( $modsince );
$ismodsince = wfTimestamp( TS_MW, $modsinceTime ? $modsinceTime : 1 );
wfDebug( "$fname: -- client send If-Modified-Since: " . $modsince . "\n", false );
wfDebug( "$fname: -- we might send Last-Modified : $lastmod\n", false );
if( ($ismodsince >= $timestamp ) && $wgUser->validateCache( $ismodsince ) && $ismodsince >= $wgCacheEpoch ) {
$this->setResponseCode( "304 Not Modified" );
$this->disable();
$this->mLastModified = $lastmod;
wfDebug( "$fname: CACHED client: $ismodsince ; user: $wgUser->mTouched ; page: $timestamp ; site $wgCacheEpoch\n", false );
return true;
} else {
wfDebug( "$fname: READY client: $ismodsince ; user: $wgUser->mTouched ; page: $timestamp ; site $wgCacheEpoch\n", false );
$this->mLastModified = $lastmod;
}
} else {
wfDebug( "$fname: client did not send If-Modified-Since header\n", false );
$this->mLastModified = $lastmod;
}
}
function loadFromMemcached( $mckey, $touched ) {
global $wgMemc;
if ( !$touched ) return false;
$mcvalue = $wgMemc->get( $mckey );
if ( $mcvalue ) {
# Check to see if the value has been invalidated
if ( $touched <= $mcvalue['timestamp'] ) {
wfDebug( "Got $mckey from cache\n" );
$this->mText = $mcvalue['value'];
return true;
} else {
wfDebug( "$mckey has expired\n" );
}
}
return false;
}
function storeInMemcached( $mckey, $expiry = 86400 ) {
global $wgMemc;
$wgMemc->set( $mckey,
array(
'timestamp' => wfTimestampNow(),
'value' => $this->mText
), $expiry
);
return true;
}
}
?>
|