1 <?php
2 
3 namespace dokuwiki;
4 
5 use dokuwiki\Extension\Event;
6 use dokuwiki\Sitemap\Mapper;
7 use dokuwiki\Subscriptions\BulkSubscriptionSender;
8 use dokuwiki\ChangeLog\ChangeLog;
9 
10 /**
11  * Class TaskRunner
12  *
13  * Run an asynchronous task.
14  */
15 class TaskRunner
16 {
17     /**
18      * Run the next task
19      *
20      * @todo refactor to remove dependencies on globals
21      * @triggers INDEXER_TASKS_RUN
22      */
23     public function run()
24     {
25         global $INPUT, $conf, $ID;
26 
27         // keep running after browser closes connection
28         @ignore_user_abort(true);
29 
30         // check if user abort worked, if yes send output early
31         $defer = !@ignore_user_abort() || $conf['broken_iua'];
32         $output = $INPUT->has('debug') && $conf['allowdebug'];
33         if (!$defer && !$output) {
34             $this->sendGIF();
35         }
36 
37         $ID = cleanID($INPUT->str('id'));
38 
39         // Catch any possible output (e.g. errors)
40         if (!$output) {
41             ob_start();
42         } else {
43             header('Content-Type: text/plain');
44         }
45 
46         // run one of the jobs
47         $tmp = []; // No event data
48         $evt = new Event('INDEXER_TASKS_RUN', $tmp);
49         if ($evt->advise_before()) {
50             if (
51                 !(
52                 $this->runIndexer() ||
53                 $this->runSitemapper() ||
54                 $this->sendDigest() ||
55                 $this->runTrimRecentChanges() ||
56                 $this->runTrimRecentChanges(true))
57             ) {
58                 $evt->advise_after();
59             }
60         }
61 
62         if (!$output) {
63             ob_end_clean();
64             if ($defer) {
65                 $this->sendGIF();
66             }
67         }
68     }
69 
70     /**
71      * Just send a 1x1 pixel blank gif to the browser
72      *
73      * @author Andreas Gohr <andi@splitbrain.org>
74      * @author Harry Fuecks <fuecks@gmail.com>
75      */
76     protected function sendGIF()
77     {
78         $img = base64_decode('R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAEALAAAAAABAAEAAAIBTAA7');
79         header('Content-Type: image/gif');
80         header('Content-Length: ' . strlen($img));
81         header('Connection: Close');
82         echo $img;
83         tpl_flush();
84         // Browser should drop connection after this
85         // Thinks it's got the whole image
86     }
87 
88     /**
89      * Trims the recent changes cache (or imports the old changelog) as needed.
90      *
91      * @param bool $media_changes   If the media changelog shall be trimmed instead of
92      *                              the page changelog
93      *
94      * @return bool
95      * @triggers TASK_RECENTCHANGES_TRIM
96      * @author Ben Coburn <btcoburn@silicodon.net>
97      */
98     protected function runTrimRecentChanges($media_changes = false)
99     {
100         global $conf;
101 
102         echo "runTrimRecentChanges($media_changes): started" . NL;
103 
104         $fn = ($media_changes ? $conf['media_changelog'] : $conf['changelog']);
105 
106         // Trim the Recent Changes
107         // Trims the recent changes cache to the last $conf['changes_days'] recent
108         // changes or $conf['recent'] items, which ever is larger.
109         // The trimming is only done once a day.
110         if (
111             file_exists($fn) &&
112             (@filemtime($fn . '.trimmed') + 86400) < time() &&
113             !file_exists($fn . '_tmp')
114         ) {
115             @touch($fn . '.trimmed');
116             io_lock($fn);
117             $lines = file($fn);
118             if (count($lines) <= $conf['recent']) {
119                 // nothing to trim
120                 io_unlock($fn);
121                 echo "runTrimRecentChanges($media_changes): finished" . NL;
122                 return false;
123             }
124 
125             io_saveFile($fn . '_tmp', '');          // presave tmp as 2nd lock
126             $trim_time = time() - $conf['recent_days'] * 86400;
127             $out_lines = [];
128             $old_lines = [];
129             $counter = count($lines);
130             for ($i = 0; $i < $counter; $i++) {
131                 $log = ChangeLog::parseLogLine($lines[$i]);
132                 if ($log === false) {
133                     continue; // discard junk
134                 }
135 
136                 if ($log['date'] < $trim_time) {
137                     // keep old lines for now (append .$i to prevent key collisions)
138                     $old_lines[$log['date'] . ".$i"] = $lines[$i];
139                 } else {
140                     // definitely keep these lines
141                     $out_lines[$log['date'] . ".$i"] = $lines[$i];
142                 }
143             }
144 
145             if (count($lines) === count($out_lines)) {
146                 // nothing to trim
147                 @unlink($fn . '_tmp');
148                 io_unlock($fn);
149                 echo "runTrimRecentChanges($media_changes): finished" . NL;
150                 return false;
151             }
152 
153             // sort the final result, it shouldn't be necessary,
154             //   however the extra robustness in making the changelog cache self-correcting is worth it
155             ksort($out_lines);
156             $extra = $conf['recent'] - count($out_lines);        // do we need extra lines do bring us up to minimum
157             if ($extra > 0) {
158                 ksort($old_lines);
159                 $out_lines = array_merge(array_slice($old_lines, -$extra), $out_lines);
160             }
161 
162             $eventData = [
163                 'isMedia' => $media_changes,
164                 'trimmedChangelogLines' => $out_lines,
165                 'removedChangelogLines' => $extra > 0 ? array_slice($old_lines, 0, -$extra) : $old_lines,
166             ];
167             Event::createAndTrigger('TASK_RECENTCHANGES_TRIM', $eventData);
168             $out_lines = $eventData['trimmedChangelogLines'];
169 
170             // save trimmed changelog
171             io_saveFile($fn . '_tmp', implode('', $out_lines));
172             @unlink($fn);
173             if (!rename($fn . '_tmp', $fn)) {
174                 // rename failed so try another way...
175                 io_unlock($fn);
176                 io_saveFile($fn, implode('', $out_lines));
177                 @unlink($fn . '_tmp');
178             } else {
179                 io_unlock($fn);
180             }
181             echo "runTrimRecentChanges($media_changes): finished" . NL;
182             return true;
183         }
184 
185         // nothing done
186         echo "runTrimRecentChanges($media_changes): finished" . NL;
187         return false;
188     }
189 
190 
191     /**
192      * Runs the indexer for the current page
193      *
194      * @author Andreas Gohr <andi@splitbrain.org>
195      */
196     protected function runIndexer()
197     {
198         global $ID;
199         echo 'runIndexer(): started' . NL;
200 
201         if ((string) $ID === '') {
202             return false;
203         }
204 
205         // do the work
206         return idx_addPage($ID, true);
207     }
208 
209     /**
210      * Builds a Google Sitemap of all public pages known to the indexer
211      *
212      * The map is placed in the root directory named sitemap.xml.gz - This
213      * file needs to be writable!
214      *
215      * @author Andreas Gohr
216      * @link   https://www.google.com/webmasters/sitemaps/docs/en/about.html
217      */
218     protected function runSitemapper()
219     {
220         echo 'runSitemapper(): started' . NL;
221         $result = Mapper::generate() && Mapper::pingSearchEngines();
222         echo 'runSitemapper(): finished' . NL;
223         return $result;
224     }
225 
226     /**
227      * Send digest and list mails for all subscriptions which are in effect for the
228      * current page
229      *
230      * @author Adrian Lang <lang@cosmocode.de>
231      */
232     protected function sendDigest()
233     {
234         global $ID;
235 
236         echo 'sendDigest(): started' . NL;
237         if (!actionOK('subscribe')) {
238             echo 'sendDigest(): disabled' . NL;
239             return false;
240         }
241         $sub = new BulkSubscriptionSender();
242         $sent = $sub->sendBulk($ID);
243 
244         echo "sendDigest(): sent $sent mails" . NL;
245         echo 'sendDigest(): finished' . NL;
246         return (bool)$sent;
247     }
248 }
249