3 * StatusNet - the distributed open-source microblogging tool
4 * Copyright (C) 2011, StatusNet, Inc.
6 * A notice stream that filters its upstream content
10 * This program is free software: you can redistribute it and/or modify
11 * it under the terms of the GNU Affero General Public License as published by
12 * the Free Software Foundation, either version 3 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Affero General Public License for more details.
20 * You should have received a copy of the GNU Affero General Public License
21 * along with this program. If not, see <http://www.gnu.org/licenses/>.
25 * @author Evan Prodromou <evan@status.net>
26 * @copyright 2011 StatusNet, Inc.
27 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPL 3.0
28 * @link http://status.net/
31 if (!defined('STATUSNET')) {
32 // This check helps protect against security problems;
33 // your code file can't be executed directly from the web.
38 * A class for presenting a filtered notice stream based on an upstream stream
42 * @author Evan Prodromou <evan@status.net>
43 * @copyright 2011 StatusNet, Inc.
44 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPL 3.0
45 * @link http://status.net/
48 abstract class FilteringNoticeStream extends NoticeStream
52 function __construct($upstream)
54 $this->upstream = $upstream;
57 abstract function filter($notice);
59 function getNotices($offset, $limit, $sinceId=null, $maxId=null)
61 // "offset" is virtual; we have to get a lot
62 $total = $offset + $limit;
69 // Keep going till we have $total notices in $notices array,
70 // or we get nothing from upstream.
77 $raw = $this->upstream->getNotices($startAt, $askFor, $sinceId, $maxId);
85 $notices = $raw->fetchAll();
87 $this->prefill($notices);
89 foreach ($notices as $notice) {
90 if ($this->filter($notice)) {
91 $filtered[] = $notice;
92 if (count($filtered) >= $total) {
98 // XXX: make these smarter; factor hit rate into $askFor
102 $hits = count($filtered);
107 $askFor = max(min(2 * $askFor, NOTICES_PER_PAGE * 50), NOTICES_PER_PAGE);
109 $askFor = max(min(intval(ceil(($total - $hits)*$startAt/$hits)), NOTICES_PER_PAGE * 50), NOTICES_PER_PAGE);
114 } while (count($filtered) < $total && $results >= $lastAsk);
116 return new ArrayWrapper(array_slice($filtered, $offset, $limit));
119 function getNoticeIds($offset, $limit, $sinceId, $maxId)
121 $notices = $this->getNotices($offset, $limit, $sinceId, $maxId);
125 while ($notices->fetch()) {
126 $ids[] = $notices->id;
132 function prefill($notices)