plugins/Realtime/Realtime_channel.php

   1 <?php
   2 /**
   3  * StatusNet - the distributed open-source microblogging tool
   4  * Copyright (C) 2011, StatusNet, Inc.
   5  *
   6  * A channel for real-time browser data
   7  *
   8  * PHP version 5
   9  *
  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.
  14  *
  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.
  19  *
  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/>.
  22  *
  23  * @category  Realtime
  24  * @package   StatusNet
  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/
  29  */
  30
  31 if (!defined('STATUSNET')) {
  32     exit(1);
  33 }
  34
  35 /**
  36  * A channel for real-time browser data
  37  *
  38  * For each user currently browsing the site, we want to know which page they're on
  39  * so we can send real-time updates to their browser.
  40  *
  41  * @category Realtime
  42  * @package  StatusNet
  43  * @author   Evan Prodromou <evan@status.net>
  44  * @license  http://www.fsf.org/licensing/licenses/agpl.html AGPLv3
  45  * @link     http://status.net/
  46  *
  47  * @see      DB_DataObject
  48  */
  49
  50 class Realtime_channel extends Managed_DataObject
  51 {
  52         const TIMEOUT = 1800; // 30 minutes
  53
  54     public $__table = 'realtime_channel'; // table name
  55
  56     public $user_id;       // int -> user.id, can be null
  57     public $action;        // string
  58     public $arg1;          // argument
  59     public $arg2;          // argument, usually null
  60     public $channel_key;   // 128-bit shared secret key
  61     public $created;       // created date
  62     public $modified;      // modified date
  63
  64     /**
  65      * Get an instance by key
  66      *
  67      * This is a utility method to get a single instance with a given key value.
  68      *
  69      * @param string $k Key to use to lookup (usually 'user_id' for this class)
  70      * @param mixed  $v Value to lookup
  71      *
  72      * @return Realtime_channel object found, or null for no hits
  73      *
  74      */
  75     function staticGet($k, $v=null)
  76     {
  77         return Managed_DataObject::staticGet('Realtime_channel', $k, $v);
  78     }
  79
  80     /**
  81      * Get an instance by compound key
  82      *
  83      * @param array $kv array of key-value mappings
  84      *
  85      * @return Realtime_channel object found, or null for no hits
  86      *
  87      */
  88     function pkeyGet($kv)
  89     {
  90         return Managed_DataObject::pkeyGet('Realtime_channel', $kv);
  91     }
  92
  93     /**
  94      * The One True Thingy that must be defined and declared.
  95      */
  96     public static function schemaDef()
  97     {
  98         return array(
  99             'description' => 'A channel of realtime notice data',
 100             'fields' => array(
 101                 'user_id' => array('type' => 'int',
 102                                                                    'not null' => false,
 103                                                                    'description' => 'user viewing page; can be null'),
 104                 'action' => array('type' => 'varchar',
 105                                                   'length' => 255,
 106                                                                   'not null' => true,
 107                                                                   'description' => 'page being viewed'),
 108                                 'arg1' => array('type' => 'varchar',
 109                                                             'length' => 255,
 110                                                             'not null' => false,
 111                                                             'description' => 'page argument, like username or tag'),
 112                             'arg2' => array('type' => 'varchar',
 113                                                         'length' => 255,
 114                                                         'not null' => false,
 115                                                         'description' => 'second page argument, like tag for showstream'),
 116                             'channel_key' => array('type' => 'varchar',
 117                                                    'length' => 32,
 118                                                    'not null' => true,
 119                                                    'description' => 'shared secret key for this channel'),
 120                 'created' => array('type' => 'datetime',
 121                                                                    'not null' => true,
 122                                                                    'description' => 'date this record was created'),
 123                 'modified' => array('type' => 'datetime',
 124                                                                 'not null' => true,
 125                                                             'description' => 'date this record was modified'),
 126             ),
 127             'primary key' => array('user_id', 'action', 'arg1', 'arg2'),
 128             'unique keys' => array('channel_key'),
 129             'foreign keys' => array(
 130                 'realtime_channel_user_id_fkey' => array('user', array('user_id' => 'id')),
 131             ),
 132             'indexes' => array(
 133                 'realtime_channel_modified_idx' => array('modified'),
 134             ),
 135         );
 136     }
 137
 138     static function saveNew($user_id, $action, $arg1, $arg2)
 139     {
 140         $channel = self::getChannel($user_id, $action, $arg1, $arg2);
 141
 142         $channel = new Realtime_channel();
 143
 144         $channel->user_id = $user_id;
 145         $channel->action  = $action;
 146         $channel->arg1    = $arg1;
 147         $channel->arg2    = $arg2;
 148
 149         $channel->channel_key = common_good_rand(16); // 128-bit key, 32 hex chars
 150
 151         $channel->created  = common_sql_now();
 152         $channel->modified = $channel->created;
 153
 154                 $channel->insert();
 155
 156                 return $channel;
 157     }
 158
 159     static function getChannel($user_id, $action, $arg1, $arg2)
 160     {
 161         $channel = self::pkeyGet(array('user_id' => $user_id,
 162                                                                    'action' => $action,
 163                                                                    'arg1' => $arg1,
 164                                                                    'arg2' => $arg2));
 165
 166         // Ignore (and delete!) old channels
 167
 168         if (!empty($channel)) {
 169                         $modTime = strtotime($channel->modified);
 170                         if ((time() - $modTime) > self::TIMEOUT) {
 171                                 $channel->delete();
 172                                 $channel = null;
 173                         }
 174         }
 175
 176         return $channel;
 177     }
 178 }