Zabbix

/*

** Zabbix

** Copyright (C) 2001-2022 Zabbix SIA

**

** This program is free software; you can redistribute it and/or modify

** it under the terms of the GNU General Public License as published by

** the Free Software Foundation; either version 2 of the License, or

** (at your option) any later version.

**

** This program is distributed in the hope that it will be useful,

** but WITHOUT ANY WARRANTY; without even the implied warranty of

** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

** GNU General Public License for more details.

**

** You should have received a copy of the GNU General Public License

** along with this program; if not, write to the Free Software

** Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

**/

​

​

ZBX_LocalStorage.defines = {

    PREFIX_SEPARATOR: ':',

    KEEP_ALIVE_INTERVAL: 30,

    SYNC_INTERVAL_MS: 500,

    KEY_SESSIONS: 'sessions',

    KEY_LAST_WRITE: 'key_last_write'

};

​

/**

 * Local storage wrapper. Implements singleton.

 *

 * @param {string} version  Mandatory parameter.

 * @param {string} prefix   Used to distinct keys between sessions within same domain.

 */

function ZBX_LocalStorage(version, prefix) {

    if (!version || !prefix) {

        throw 'Local storage instantiation must be versioned, and prefixed.';

    }

​

    if (ZBX_LocalStorage.instance) {

        return ZBX_LocalStorage.instance;

    }

​

    ZBX_LocalStorage.sessionid = prefix;

    ZBX_LocalStorage.prefix = prefix + ZBX_LocalStorage.defines.PREFIX_SEPARATOR;

    ZBX_LocalStorage.instance = this;

    ZBX_LocalStorage.signature = (Math.random() % 9e6).toString(36).substr(2);

​

    this.abs_to_rel_keymap = {};

    this.key_last_write = {};

    this.rel_keys = {};

    this.abs_keys = {};

​

    this.addKey('version');

    this.addKey('tabs.lastseen');

    this.addKey('notifications.list');

    this.addKey('notifications.active_tabid');

    this.addKey('notifications.user_settings');

    this.addKey('notifications.alarm_state');

    this.addKey('dashboard.copied_widget');

    this.addKey('web.notifications.pos');

​

    if (this.readKey('version') != version) {

        this.truncate();

        this.writeKey('version', version);

    }

​

    this.register();

}

​

/**

 * @param {string} key  Relative key.

 * @param {callable} callback  When out of sync is observed, then new value is read, and passed into callback.

 *

 * @return {string}

 */

ZBX_LocalStorage.prototype.onKeySync = function(key, callback) {

    this.rel_keys[key].subscribeSync(callback);

};

​

/**

 * @param {string} key  Relative key.

 * @param {callable} callback  Executed on storage event for this key.

 *

 * @return {string}

 */

ZBX_LocalStorage.prototype.onKeyUpdate = function(key, callback) {

    this.rel_keys[key].subscribe(callback);

};

​

/**