Guard the usage of localStorage to catch exceptions. (#270)

Author: molily

src/components/controllers/repl/index.js

@@ -3,6 +3,7 @@ import { debounce } from 'decko';
 import codeExample from './code-example.txt';
 import todoExample from './todo-example.txt';
 import style from './style';
+import { localStorageGet, localStorageSet } from '../../../lib/localstorage';
 
 const EXAMPLES = [
 	{
@@ -18,7 +19,7 @@ const EXAMPLES = [
 export default class Repl extends Component {
 	state = {
 		loading: 'Initializing...',
-		code: localStorage.getItem('preact-www-repl-code') || codeExample
+		code: localStorageGet('preact-www-repl-code') || codeExample
 	};
 
 	constructor(props, context) {
@@ -87,7 +88,7 @@ export default class Repl extends Component {
 	componentDidUpdate = debounce(500, () => {
 		let { code } = this.state;
 		if (code===codeExample) code = '';
-		localStorage.setItem('preact-www-repl-code', code || '');
+		localStorageSet('preact-www-repl-code', code || '');
 	})
 
 	componentWillReceiveProps({ code }) {

src/components/github-stars.js

@@ -1,5 +1,6 @@
 import { h, Component } from 'preact';
 import { memoize } from 'decko';
+import { localStorageGet, localStorageSet } from '../lib/localstorage';
 
 const githubStars = memoize( repo => fetch('//api.github.com/repos/'+repo)
 	.then( r => r.json() )
@@ -11,12 +12,12 @@ if (typeof window!=='undefined') window.githubStars = githubStars;
 
 export default class GithubStars extends Component {
 	state = {
-		stars: localStorage._stars || ''
+		stars: localStorageGet('_stars') || ''
 	};
 
 	setStars = stars => {
 		if (stars && stars!=this.state.stars) {
-			localStorage._stars = stars;
+			localStorageSet('_stars', stars);
 			this.setState({ stars });
 		}
 	};

src/lib/localstorage.js

@@ -0,0 +1,13 @@
+export const localStorageGet = (key) => {
+	try {
+		return localStorage.getItem(key);
+	} catch (e) {
+		return null;
+	}
+};
+
+export const localStorageSet = (key, value) => {
+	try {
+		localStorage.setItem(key, value);
+	} catch (e) {}
+};

src/store.js

@@ -1,6 +1,7 @@
 import createStore from './lib/store';
 import getDefaultLanguage from './lib/default-language';
 import config from './config';
+import { localStorageSet, localStorageGet } from './lib/localstorage';
 
 const SAVE = ['lang'];
 
@@ -22,13 +23,13 @@ export default () => {
 function saveState(state) {
 	let saved = {};
 	for (let i=SAVE.length; i--; ) saved[SAVE[i]] = state[SAVE[i]];
-	localStorage.state = JSON.stringify(saved);
+	localStorageSet('state', JSON.stringify(saved));
 }
 
 function getSavedState() {
 	let state;
 	try {
-		state = JSON.parse(localStorage.state);
+		state = JSON.parse(localStorageGet('state'));
 	} catch (e) {}
 	return state || {};
 }