dom-storage.js/lib/index.js

116 lines
2.4 KiB
JavaScript

/*jshint node:true es5:true laxcomma:true laxbreak:true*/
// http://www.rajdeepd.com/articles/chrome/localstrg/LocalStorageSample.htm
// NOTE:
// this varies from actual localStorage in some subtle ways
// also, there is no persistence
// TODO persist
(function () {
"use strict";
var fs = require('fs')
;
function Storage(path, opts) {
opts = opts || {};
var db
;
Object.defineProperty(this, '___priv_bk___', {
value: {
path: path
}
, writable: false
, enumerable: false
});
Object.defineProperty(this, '___priv_strict___', {
value: !!opts.strict
, writable: false
, enumerable: false
});
try {
db = JSON.parse(fs.readFileSync(path));
} catch(e) {
db = {};
}
Object.keys(db).forEach(function (key) {
this[key] = db[key];
}, this);
}
Storage.prototype.getItem = function (key) {
if (this.hasOwnProperty(key)) {
return this.___priv_strict___ && String(this[key]) || this[key];
}
return null;
};
Storage.prototype.setItem = function (key, val) {
this[key] = this.___priv_strict___ && String(val) || val;
this.___save___();
};
Storage.prototype.removeItem = function (key) {
delete this[key];
this.___save___();
};
Storage.prototype.clear = function () {
var self = this;
// filters out prototype keys
Object.keys(self).forEach(function (key) {
self[key] = undefined;
delete self[key];
});
};
Storage.prototype.key = function (i) {
i = i || 0;
return Object.keys(this)[i];
};
Storage.prototype.__defineGetter__('length', function () {
return Object.keys(this).length;
});
Storage.prototype.___save___ = function () {
var self = this
;
if (!this.___priv_bk___.path) {
return;
}
if (this.___priv_bk___.lock) {
this.___priv_bk___.wait = true;
return;
}
this.___priv_bk___.lock = true;
fs.writeFile(this.___priv_bk___.path, JSON.stringify(this), 'utf8', function (e) {
self.___priv_bk___.lock = false;
if (e) {
return;
}
if (self.___priv_bk___.wait) {
self.___priv_bk___.wait = false;
self.___save___();
}
});
};
Object.defineProperty(Storage, 'create', {
value: function (path, opts) {
return new Storage(path, opts);
}
, writable: false
, enumerable: false
});
module.exports = Storage;
}());