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