signal-desktop/js/storage.js

/*
 * vim: ts=4:sw=4:expandtab
 */
;(function() {
    'use strict';
    window.Whisper = window.Whisper || {};
    var Item = Backbone.Model.extend({
      database: Whisper.Database,
      storeName: 'items'
    });
    var ItemCollection = Backbone.Collection.extend({
        model: Item,
        storeName: 'items',
        database: Whisper.Database,
    });

    var ready = false;
    var items = new ItemCollection();
    items.on('reset', function() { ready = true; });
    window.storage = {
        /*****************************
        *** Base Storage Routines ***
        *****************************/
        put: function(key, value) {
            if (value === undefined) {
                throw new Error("Tried to store undefined");
            }
            if (!ready) {
                console.log('Called storage.put before storage is ready. key:', key);
            }
            var item = items.add({id: key, value: value}, {merge: true});
            return new Promise(function(resolve, reject) {
                item.save().then(resolve, reject);
            });
        },

        get: function(key, defaultValue) {
            var item = items.get("" + key);
            if (!item) {
                return defaultValue;
            }
            return item.get('value');
        },

        remove: function(key) {
            var item = items.get("" + key);
            if (item) {
                items.remove(item);
                return new Promise(function(resolve, reject) {
                    item.destroy().then(resolve, reject);
                });
            }
            return Promise.resolve();
        },

        onready: function(callback) {
            if (ready) {
                callback();
            } else {
                items.on('reset', callback);
            }
        },

        fetch: function() {
            return new Promise((resolve, reject) => {
                items.fetch({reset: true})
                    .fail(() => reject(new Error('Failed to fetch from storage.' +
                        ' This may be due to an unexpected database version.')))
                    .always(resolve);
            });
        },

        reset: function() {
            items.reset();
        }
    };
    window.textsecure = window.textsecure || {};
    window.textsecure.storage = window.textsecure.storage || {};
    window.textsecure.storage.impl = window.storage;
})();