lib/queuehandler.php

   1 <?php
   2 /*
   3  * Laconica - a distributed open-source microblogging tool
   4  * Copyright (C) 2008, Controlez-Vous, Inc.
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU Affero General Public License as published by
   8  * the Free Software Foundation, either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU Affero General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Affero General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 define('CLAIM_TIMEOUT', 1200);
  21
  22 if (!defined('LACONICA')) { exit(1); }
  23
  24 require_once(INSTALLDIR.'/lib/daemon.php');
  25 require_once(INSTALLDIR.'/classes/Queue_item.php');
  26 require_once(INSTALLDIR.'/classes/Notice.php');
  27
  28 class QueueHandler extends Daemon {
  29
  30         var $_id = 'generic';
  31
  32         function QueueHandler($id=NULL) {
  33                 if ($id) {
  34                         $this->set_id($id);
  35                 }
  36         }
  37
  38         function class_name() {
  39                 return ucfirst($this->transport()) . 'Handler';
  40         }
  41
  42         function name() {
  43                 return strtolower($this->class_name().'.'.$this->get_id());
  44         }
  45
  46         function get_id() {
  47                 return $this->_id;
  48         }
  49
  50         function set_id($id) {
  51                 $this->_id = $id;
  52         }
  53
  54         function transport() {
  55                 return NULL;
  56         }
  57
  58         function start() {
  59         }
  60
  61         function finish() {
  62         }
  63
  64         function handle_notice($notice) {
  65                 return true;
  66         }
  67
  68         function run() {
  69                 if (!$this->start()) {
  70                         return false;
  71                 }
  72                 $this->log(LOG_INFO, 'checking for queued notices');
  73                 $transport = $this->transport();
  74                 do {
  75                         $qi = Queue_item::top($transport);
  76                         if ($qi) {
  77                                 $this->log(LOG_INFO, 'Got item enqueued '.common_exact_date($qi->created));
  78                                 $notice = Notice::staticGet($qi->notice_id);
  79                                 if ($notice) {
  80                                         $this->log(LOG_INFO, 'broadcasting notice ID = ' . $notice->id);
  81                                         # XXX: what to do if broadcast fails?
  82                                         $result = $this->handle_notice($notice);
  83                                         if (!$result) {
  84                                                 $this->log(LOG_WARNING, 'Failed broadcast for notice ID = ' . $notice->id);
  85                                                 $orig = $qi;
  86                                                 $qi->claimed = NULL;
  87                                                 $qi->update($orig);
  88                                                 $this->log(LOG_WARNING, 'Abandoned claim for notice ID = ' . $notice->id);
  89                                                 continue;
  90                                         }
  91                                         $this->log(LOG_INFO, 'finished broadcasting notice ID = ' . $notice->id);
  92                                         $notice->free();
  93                                         unset($notice);
  94                                         $notice = NULL;
  95                                 } else {
  96                                         $this->log(LOG_WARNING, 'queue item for notice that does not exist');
  97                                 }
  98                                 $qi->delete();
  99                                 $qi->free();
 100                                 unset($qi);
 101                                 $this->idle(0);
 102                         } else {
 103                                 $this->clear_old_claims();
 104                                 $this->idle(5);
 105                         }
 106                 } while (true);
 107                 if (!$this->finish()) {
 108                         return false;
 109                 }
 110                 return true;
 111         }
 112
 113         function idle($timeout=0) {
 114                 if ($timeout>0) {
 115                         sleep($timeout);
 116                 }
 117         }
 118
 119         function clear_old_claims() {
 120                 $qi = new Queue_item();
 121                 $qi->transport = $this->transport();
 122                 $qi->whereAdd('now() - claimed > '.CLAIM_TIMEOUT);
 123                 $qi->update(DB_DATAOBJECT_WHEREADD_ONLY);
 124                 $qi->free();
 125                 unset($qi);
 126         }
 127
 128         function log($level, $msg) {
 129                 common_log($level, $this->class_name() . ' ('. $this->get_id() .'): '.$msg);
 130         }
 131 }
 132