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702 lines
31 KiB
JavaScript
702 lines
31 KiB
JavaScript
/**
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* cache.js : Provide a cache for assets from the ZIM archive using indexedDB, localStorage or memory cache
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*
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* Copyright 2018 Mossroy, Jaifroid and contributors
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* License GPL v3:
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*
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* This file is part of Kiwix.
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*
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* Kiwix is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* Kiwix is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with Kiwix (file LICENSE-GPLv3.txt). If not, see <http://www.gnu.org/licenses/>
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*/
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'use strict';
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define(['q', 'settingsStore', 'uiUtil'], function(Q, settingsStore, uiUtil) {
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var CACHE_NAME = 'kiwixjs-assetCache'; // Set the database or cache name here
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var objStore = 'Assets'; // Name of the object store
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// DEV: Regex below defines the permitted key types for the cache; add further types as needed
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// NB: The key type of '.zim', or '.zimaa' (etc.) is used to store a ZIM's last-accessed article
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var regexpKeyTypes = /(?:(?:^|\/)A\/.+|\.[Jj][Ss]|\.[Cc][Ss][Ss]|\.[Zz][Ii][Mm]\w{0,2})$/;
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/**
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* Tests the enviornment's caching capabilities and sets assetsCache.capability to the supported level
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*
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* @param {Function} callback Function to indicate that the capability level has been set
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*/
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function test(callback) {
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// Test for indexedDB capability
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if (typeof assetsCache.capability !== 'undefined') {
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callback(true);
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return;
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}
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// Set baseline capability
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assetsCache.capability = 'memory';
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idxDB('count', function(result) {
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if (result !== false) {
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assetsCache.capability = 'indexedDB|' + assetsCache.capability;
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} else {
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console.log("inexedDB is not supported");
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}
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// Test for Cache API
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if('caches' in window && /https?:/i.test(window.location.protocol)) {
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assetsCache.capability = 'cacheAPI|' + assetsCache.capability;
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console.log('Cache API is available, but in development in this app');
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} else {
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console.log('CacheAPI is not supported' + (/https?:/i.test(window.location.protocol) ? '' :
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' with the ' + window.location.protocol + ' protocol'));
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}
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// Test for localCache capability (this is a fallback, indexedDB is preferred because it permits more storage)
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if (typeof Storage !== "undefined") {
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try {
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// If localStorage is really supported, this won't produce an error
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var item = window.localStorage.length;
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assetsCache.capability = assetsCache.capability + '|localStorage';
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} catch (err) {
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console.log("localStorage is not supported");
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}
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}
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console.log('Setting storage type to ' + assetsCache.capability.match(/^[^|]+/)[0]);
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if (/localStorage/.test(assetsCache.capability)) {
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console.log("DEV: 'UnknownError' may be produced as part of localStorage capability detection");
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}
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callback(result);
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});
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}
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/**
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* Counts the numnber of cached assets
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*
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* @param {Function} callback which will receive an array containing [cacheType, cacheCount]
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*/
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function count(callback) {
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test(function(result) {
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var type = null;
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var description = null;
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var cacheCount = null;
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switch (assetsCache.capability.match(/^[^|]+/)[0]) {
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case 'memory':
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type = 'memory';
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description = 'Memory';
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cacheCount = assetsCache.size;
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break;
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case 'localStorage':
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type = 'localStorage';
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description = 'LocalStorage';
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cacheCount = localStorage.length;
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break;
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case 'indexedDB':
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type = 'indexedDB';
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description = 'IndexedDB';
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// Sometimes we already have the count as a result of test, so no need to look again
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if (typeof result !== 'boolean' && (result === 0 || result > 0)) {
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cacheCount = result;
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} else {
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idxDB('count', function(cacheCount) {
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callback({'type': type, 'description': description, 'count': cacheCount});
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});
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}
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break;
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case 'cacheAPI':
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type = 'cacheAPI';
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description = 'CacheAPI';
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caches.open(CACHE_NAME).then(function (cache) {
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cache.keys().then(function (keys) {
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callback({'type': type, 'description': description, 'count': keys.length});
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});
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});
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break;
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default:
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// User has turned off caching
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type = 'none';
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description = 'None';
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cacheCount = 'null';
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}
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if (cacheCount || cacheCount === 0) {
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callback({'type': type, 'description': description, 'count': cacheCount});
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}
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});
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}
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/**
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* Opens an IndexedDB database and adds or retrieves a key-value pair to it, or performs utility commands
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* on the database
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*
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* @param {String} keyOrCommand The key of the value to be written or read, or commands 'clear' (clears objStore),
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* 'count' (counts number of objects in objStore), 'delete' (deletes a record with key passed in valueOrCallback)
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* @param {Variable} valueOrCallback The value to write, or a callback function for read and command transactions
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* @param {Function} callback Callback for write transactions only
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*/
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function idxDB(keyOrCommand, valueOrCallback, callback) {
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var value = callback ? valueOrCallback : null;
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var rtnFn = callback || valueOrCallback;
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if (typeof window.indexedDB === 'undefined') {
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rtnFn(false);
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return;
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}
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// Open (or create) the database
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var open = indexedDB.open(CACHE_NAME, 1);
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open.onerror = function(e) {
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// Suppress error reporting if testing (older versions of Firefox support indexedDB but cannot use it with
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// the file:// protocol, so will report an error)
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if (assetsCache.capability !== 'test') {
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console.error('IndexedDB failed to open: ' + open.error.message);
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}
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rtnFn(false);
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};
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// Create the schema
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open.onupgradeneeded = function() {
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var db = open.result;
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var store = db.createObjectStore(objStore);
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};
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open.onsuccess = function() {
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// Start a new transaction
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var db = open.result;
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// Set the store to readwrite or read only according to presence or not of value variable
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var tx = value !== null || keyOrCommand === 'clear' ? db.transaction(objStore, "readwrite") : db.transaction(objStore);
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var store = tx.objectStore(objStore);
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var processData;
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// Process commands
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if (keyOrCommand === 'clear') {
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// Delete all keys and values in the store
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processData = store.clear();
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} else if (keyOrCommand === 'count') {
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// Count the objects in the store
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processData = store.count();
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} else if (keyOrCommand === 'delete') {
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// Delete the record with key set to value
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processData = store.delete(value);
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} else {
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// Request addition or retrieval of data
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processData = value !== null ? store.put(value, keyOrCommand) : store.get(keyOrCommand);
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}
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// Call the callback with the result
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processData.onsuccess = function(e) {
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if (keyOrCommand === 'delete') {
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rtnFn(true);
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} else {
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rtnFn(processData.result);
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}
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};
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processData.onerror = function(e){
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console.error('IndexedDB command failed: ' + processData.error);
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rtnFn(false);
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};
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// Close the db when the transaction is done
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tx.oncomplete = function() {
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db.close();
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};
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};
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}
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/**
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* Opens a CacheAPI cache and adds or retrieves a key-value pair to it, or performs utility commands
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* on the cache. This interface also allows the use of callbacks inside the Cache Promise API for ease of
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* interoperability with the interface for idxDB code above.
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*
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* @param {String} keyOrCommand The key of the value to be written or read, or commands 'clear' (clears cache),
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* 'delete' (deletes a record with key passed in valueOrCallback)
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* @param {Variable} valueOrCallback The value to write, or a callback function for read and command transactions
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* @param {Function} callback Callback for write transactions only
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*/
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function cacheAPI(keyOrCommand, valueOrCallback, callback) {
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var value = callback ? valueOrCallback : null;
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var rtnFn = callback || valueOrCallback;
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// Process commands
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if (keyOrCommand === 'clear') {
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caches.delete(CACHE_NAME).then(rtnFn);
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} else if (keyOrCommand === 'delete') {
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caches.open(CACHE_NAME).then(function(cache) {
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cache.delete(value).then(rtnFn);
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});
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} else if (value === null) {
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// Request retrieval of data
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caches.open(CACHE_NAME).then(function(cache) {
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cache.match('../' + keyOrCommand).then(function(response) {
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if (!response) {
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rtnFn(null);
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} else {
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response.text().then(function(data) {
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rtnFn(data);
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});
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}
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}).catch(function(err) {
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console.error('Unable to match assets from Cache API!', err);
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rtnFn(null);
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});
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});
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} else {
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// Request storing of data in cache
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caches.open(CACHE_NAME).then(function(cache) {
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// Construct a Response from value
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var response = new Response(value);
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cache.put('../' + keyOrCommand, response).then(function() {
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rtnFn(true);
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}).catch(function(err) {
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console.error('Unable to store assets in Cache API!', err);
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rtnFn(null);
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});
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});
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}
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}
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/**
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* Stores information about the last visited page in a cookie and, if available, in localStorage or indexedDB
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*
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* @param {String} zimFile The filename (or name of first file in set) of the ZIM archive
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* @param {String} article The URL of the article (including namespace)
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* @param {String} content The content of the page to be stored
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* @param {Function} callback Callback function to report the outcome of the operation
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*/
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function setArticle(zimFile, article, content, callback) {
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// Prevent storage if user has deselected the option in Configuration
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if (!params.rememberLastPage) {
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callback(-1);
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return;
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}
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settingsStore.setItem(zimFile, article, Infinity);
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setItem(zimFile, content, function(response) {
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callback(response);
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});
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}
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/**
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* Retrieves article contents from cache only if the article's key has been stored in settings store
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* (since checking the store is synchronous, it prevents unnecessary async cache lookups)
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*
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* @param {String} zimFile The filename (or name of first file in set) of the ZIM archive
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* @param {String} article The URL of the article to be retrieved (including namespace)
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* @param {Function} callback The function to call with the result
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*/
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function getArticle(zimFile, article, callback) {
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if (settingsStore.getItem(zimFile) === article) {
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getItem(zimFile, callback);
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} else {
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callback(false);
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}
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}
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/**
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* Caches the contents of an asset in memory or local storage
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*
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* @param {String} key The database key of the asset to cache
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* @param {String} contents The file contents to be stored in the cache
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* @param {Function} callback Callback function to report outcome of operation
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*/
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function setItem(key, contents, callback) {
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// Prevent use of storage if user has deselected the option in Configuration
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// or if the asset is of the wrong type
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if (params.useCache === false || !regexpKeyTypes.test(key)) {
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callback(-1);
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return;
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}
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// Check if we're actually setting an article
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var keyArticle = key.match(/([^/]+)\/(A\/.+$)/);
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if (keyArticle) { // We're setting an article, so go to setArticle function
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setArticle(keyArticle[1], keyArticle[2], contents, callback);
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return;
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}
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// Post a message to the UI that we are caching an asset
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var shortTitle = key.replace(/[^/]+\//g, '').substring(0, 18);
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document.getElementById('cachingAssets').innerHTML = 'Caching ' + shortTitle + '...';
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if (/^localStorage/.test(assetsCache.capability)) {
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localStorage.setItem(key, contents);
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} else {
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assetsCache.set(key, contents);
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}
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if (/^indexedDB/.test(assetsCache.capability)) {
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idxDB(key, contents, function(result) {
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callback(result);
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});
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} else if (/^cacheAPI/.test(assetsCache.capability)) {
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cacheAPI(key, contents, function(result) {
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callback(result);
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});
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} else {
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callback(key);
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}
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}
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/**
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* Retrieves a ZIM file asset that has been cached with the addItem function
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* either from the memory cache or local storage
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*
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* @param {String} key The database key of the asset to retrieve
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* @param {Function} callback The function to call with the result
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*/
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function getItem(key, callback) {
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// Only look up assets of the type stored in the cache
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if (!regexpKeyTypes.test(key)) {
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callback(false);
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return;
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}
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// Check if we're actually calling an article
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// DEV: See above about this regex (may need expanding)
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var keyArticle = key.match(/([^/]+)\/(A\/.+$)/);
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if (keyArticle) { // We're retrieving an article, so go to getArticle function
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getArticle(keyArticle[1], keyArticle[2], callback);
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return;
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}
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var contents = null;
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if (assetsCache.has(key)) {
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contents = assetsCache.get(key);
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callback(contents);
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} else if (/^localStorage/.test(assetsCache.capability)) {
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contents = localStorage.getItem(key);
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callback(contents);
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} else if (/^cacheAPI/.test(assetsCache.capability)) {
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cacheAPI(key, function(contents) {
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callback(contents);
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});
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} else if (/^indexedDB/.test(assetsCache.capability)) {
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idxDB(key, function(contents) {
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if (typeof contents !== 'undefined') {
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// Also store in fast memory cache to prevent repaints
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assetsCache.set(key, contents);
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}
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callback(contents);
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});
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} else {
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callback(contents);
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}
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}
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/**
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* Gets an item from the cache, or extracts it from the ZIM if it is not cached. After extracting
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* an item from the ZIM, it is added to the cache if it is of the type specified in regexpKeyTypes.
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*
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* @param {Object} selectedArchive The ZIM archive picked by the user
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* @param {String} key The cache key of the item to retrieve
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* @param {Function} callback A function to call with the result
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* @param {Object} dirEntry If the item's dirEntry has already been looked up, it can optionally be
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* supplied here (saves a redundant dirEntry lookup)
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*/
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function getItemFromCacheOrZIM(selectedArchive, key, callback, dirEntry) {
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// First check if the item is already in the cache
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var title = key.replace(/^[^/]+\//, '');
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getItem(key, function(result) {
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if (result !== null && result !== false && typeof result !== 'undefined') {
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console.log("Cache supplied " + title);
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if (/\.css$/.test(title)) {
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assetsCache.cssLoading--;
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if (assetsCache.cssLoading <= 0) {
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document.getElementById('articleContent').style.display = 'block';
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document.getElementById('cachingAssets').style.display = 'none';
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document.getElementById('searchingArticles').style.display = 'none';
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}
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}
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callback(result);
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return;
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}
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// Since there was no result, post UI messages and look up asset in ZIM
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if (regexpKeyTypes.test(key)) {
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if (!/\.css$|\.js$/.test(key)) {
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document.getElementById('cachingAssets').style.display = 'none';
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document.getElementById('searchingArticles').style.display = 'block';
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} else if (params.useCache !== false) {
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var shortTitle = key.replace(/[^/]+\//g, '').substring(0, 18);
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document.getElementById('cachingAssets').innerHTML = 'Getting ' + shortTitle + '...';
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document.getElementById('cachingAssets').style.display = 'block';
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}
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}
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// Set the read function to use according to filetype
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var readFile = regexpKeyTypes.test(title) ?
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selectedArchive.readUtf8File : selectedArchive.readBinaryFile;
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// Bypass getting dirEntry if we already have it
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var getDirEntry = dirEntry ? Q.Promise.resolve() :
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selectedArchive.getDirEntryByTitle(title);
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// Read data from ZIM
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getDirEntry.then(function(resolvedDirEntry) {
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if (dirEntry) resolvedDirEntry = dirEntry;
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if (resolvedDirEntry === null) {
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console.log("Error: asset file not found: " + title);
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callback();
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} else {
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readFile(resolvedDirEntry, function (fileDirEntry, content) {
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if (regexpKeyTypes.test(title)) {
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console.log('Cache retrieved ' + title + ' from ZIM');
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// Process any pre-cache transforms
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content = transform(content, title.replace(/^.*\.([^.]+)$/, '$1'));
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}
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// Hide article while it is rendering
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if (/^text\/html$/.test(fileDirEntry.getMimetype())) {
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// Count CSS so we can attempt to show article before JS/images are fully loaded
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var cssCount = content.match(/<(?:link)[^>]+?href=["']([^"']+)[^>]+>/ig);
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assetsCache.cssLoading = cssCount ? cssCount.length : 0;
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if (assetsCache.cssLoading) document.getElementById('articleContent').style.display = 'none';
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}
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if (/\.css$/.test(title)) {
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assetsCache.cssLoading--;
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if (assetsCache.cssLoading <= 0) {
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document.getElementById('articleContent').style.display = 'block';
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document.getElementById('cachingAssets').style.display = 'none';
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document.getElementById('searchingArticles').style.display = 'none';
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}
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}
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callback(content);
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setItem(key, content, function(result) {
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if (result === -1) {
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// Cache rejected item due to user settings
|
|
} else if (result) {
|
|
console.log('Cache: stored asset ' + title);
|
|
} else {
|
|
console.error('Cache: failed to store asset ' + title);
|
|
}
|
|
});
|
|
});
|
|
}
|
|
}).fail(function (e) {
|
|
console.error("could not find DirEntry for asset : " + title, e);
|
|
callback();
|
|
});
|
|
});
|
|
}
|
|
|
|
/**
|
|
* Clears caches (including cookie) according to the scope represented by the 'items' variable
|
|
*
|
|
* @param {String} items Either 'lastpages' (last visited pages of various archives) or 'all'
|
|
* @param {Function} callback Callback function to report the number of items cleared
|
|
*/
|
|
function clear(items, callback) {
|
|
if (!/lastpages|all/.test(items)) {
|
|
callback(false);
|
|
return;
|
|
}
|
|
// Delete cookie entries with a key containing '.zim' or '.zimaa' etc. followed by article namespace
|
|
var itemsCount = 0;
|
|
var key;
|
|
var capability = assetsCache.capability;
|
|
var zimRegExp = /(?:^|;)\s*([^=]+)=([^;]*)/ig;
|
|
var currentCookies = document.cookie;
|
|
var cookieCrumb = zimRegExp.exec(currentCookies);
|
|
while (cookieCrumb !== null) {
|
|
if (/\.zim\w{0,2}=A\//i.test(decodeURIComponent(cookieCrumb[0]))) {
|
|
key = cookieCrumb[1];
|
|
// This expiry date will cause the browser to delete the cookie on next page refresh
|
|
document.cookie = key + '=;expires=Thu, 21 Sep 1979 00:00:01 UTC;';
|
|
if (items === 'lastpages') {
|
|
assetsCache.delete(key);
|
|
// See note on loose test below
|
|
if (/localStorage/.test(capability)) {
|
|
localStorage.removeItem(key);
|
|
}
|
|
if (/indexedDB/.test(capability)) {
|
|
idxDB('delete', key, function(){});
|
|
}
|
|
if (/cacheAPI/.test(capability)) {
|
|
cacheAPI('delete', key, function(){});
|
|
}
|
|
itemsCount++;
|
|
}
|
|
}
|
|
cookieCrumb = zimRegExp.exec(currentCookies);
|
|
}
|
|
if (items === 'all') {
|
|
var result;
|
|
if (/^(memory|indexedDB|cacheAPI)/.test(capability)) {
|
|
itemsCount += assetsCache.size;
|
|
result = "assetsCache";
|
|
}
|
|
// Delete and reinitialize assetsCache
|
|
assetsCache = new Map();
|
|
assetsCache.capability = capability;
|
|
// Loose test here ensures we clear localStorage even if it wasn't being used in this session
|
|
if (/localStorage/.test(capability)) {
|
|
itemsCount += localStorage.length;
|
|
localStorage.clear();
|
|
result = result ? result + " and localStorage" : "localStorage";
|
|
}
|
|
// Loose test here ensures we clear indexedDB even if it wasn't being used in this session
|
|
if (/indexedDB/.test(capability)) {
|
|
result = result ? result + " and indexedDB" : "indexedDB";
|
|
idxDB('count', function(number) {
|
|
itemsCount += number;
|
|
idxDB('clear', function() {
|
|
result = result ? result + " (" + itemsCount + " items deleted)" : "no assets to delete";
|
|
console.log("cache.clear: " + result);
|
|
if (!/^cacheAPI/.test(capability)) callback(itemsCount);
|
|
});
|
|
});
|
|
}
|
|
// No need to use loose test here because cacheAPI trumps the others
|
|
if (/^cacheAPI/.test(capability)) {
|
|
result = result ? result + " and cacheAPI" : "cacheAPI";
|
|
count(function(number) {
|
|
itemsCount += number[1];
|
|
cacheAPI('clear', function() {
|
|
result = result ? result + " (" + itemsCount + " items deleted)" : "no assets to delete";
|
|
console.log("cache.clear: " + result);
|
|
callback(itemsCount);
|
|
});
|
|
});
|
|
}
|
|
}
|
|
if (!/^cacheAPI|indexedDB/.test(capability)) {
|
|
result = result ? result + " (" + itemsCount + " items deleted)" : "no assets to delete";
|
|
console.log("cache.clear: " + result);
|
|
callback(itemsCount);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Replaces all assets that have the given attribute in the html string with inline tags containing content
|
|
* from the cache entries corresponding to the given zimFile
|
|
* Function is intended for link or script tags, but could be extended
|
|
* Returns the substituted html in the callback function (even if no substitutions were made)
|
|
*
|
|
* @param {String} html The html string to process
|
|
* @param {String} tags The html tag or tags ('link|script') containing the asset to replace;
|
|
* multiple tags must be separated with a pipe
|
|
* @param {String} attribute The attribute that stores the URL to be substituted
|
|
* @param {String} zimFile The name of the ZIM file (or first file in the file set)
|
|
* @param {Object} selectedArchive The archive selected by the user in app.js
|
|
* @param {Function} callback The function to call with the substituted html
|
|
*/
|
|
function replaceAssetRefsWithUri(html, tags, attribute, zimFile, selectedArchive, callback) {
|
|
// Creates an array of all link tags that have the given attribute
|
|
var regexpTagsWithAttribute = new RegExp('<(?:' + tags + ')[^>]+?' + attribute + '=["\']([^"\']+)[^>]+>', 'ig');
|
|
var titles = [];
|
|
var tagArray = regexpTagsWithAttribute.exec(html);
|
|
while (tagArray !== null) {
|
|
titles.push([tagArray[0],
|
|
decodeURIComponent(tagArray[1])]);
|
|
tagArray = regexpTagsWithAttribute.exec(html);
|
|
}
|
|
if (!titles.length) {
|
|
callback(html);
|
|
}
|
|
// Iterate through the erray of titles, populating the HTML string with substituted tags containing
|
|
// a reference to the content from the Cache or from the ZIM
|
|
assetsCache.busy = titles.length;
|
|
titles.forEach(function(title) {
|
|
getItemFromCacheOrZIM(selectedArchive, zimFile + '/' + title[1], function(assetContent) {
|
|
assetsCache.busy--;
|
|
if (assetContent || assetContent === '') {
|
|
var newAssetTag = uiUtil.createNewAssetElement(title[0], attribute, assetContent);
|
|
html = html.replace(title[0], newAssetTag);
|
|
}
|
|
if (!assetsCache.busy) callback(html);
|
|
});
|
|
});
|
|
}
|
|
|
|
/**
|
|
* Provides "Server Side" transformation of textual content "served" to app.js
|
|
* For performance reasons, this is only hooked into content extracted from the ZIM: the transformed
|
|
* content will then be cached in its transformed state
|
|
*
|
|
* @param {String} string The string to transform
|
|
* @param {String} filter An optional filter: only transforms which match the filter will be executed
|
|
* @returns {String} The tranformed content
|
|
*/
|
|
function transform(string, filter) {
|
|
switch(filter) {
|
|
case 'html':
|
|
|
|
// Filter to remove any BOM (causes quirks mode in browser)
|
|
string = string.replace(/^[^<]*/, '');
|
|
|
|
// Filter to open all heading sections
|
|
string = string.replace(/(class=["'][^"']*?collapsible-(?:heading|block)(?!\s+open-block))/g,
|
|
'$1 open-block');
|
|
|
|
break;
|
|
}
|
|
return string;
|
|
}
|
|
|
|
/**
|
|
* Provide
|
|
*
|
|
* @param {Object} fileHandle The file handle that we wish to verify with the Native Filesystem API
|
|
* @param {Boolean} withWrite Indicates read only or read/write persmissions
|
|
* @returns {Promise<Boolean>} A Promise for a Boolean value indicating whether permission has been granted or not
|
|
*/
|
|
function verifyPermission(fileHandle, withWrite) {
|
|
var opts = withWrite ? { mode: 'readwrite' } : {};
|
|
return fileHandle.queryPermission(opts).then(function(permission) {
|
|
if (permission === "granted") return true;
|
|
return fileHandle.requestPermission(opts).then(function(permission) {
|
|
if (permission === 'granted') return true;
|
|
console.error('Permission for ' + fileHandle.name + ' was not granted: ' + permission);
|
|
return false;
|
|
}).catch(function(error) {
|
|
console.error('There was an error reading previously picked file ' + fileHandle.name, error);
|
|
});
|
|
});
|
|
};
|
|
|
|
/**
|
|
* Wraps a semaphor in a Promise. A function can signal that it is done by setting a sempahor to true,
|
|
* if it has first set it to false at the outset of the procedure. Ensure no other functions use the same
|
|
* sempahor. The semaphor must be an object key of the app-wide assetsCache object.
|
|
*
|
|
* @param {String} semaphor The name of a semaphor key in the assetsCache object
|
|
* @param {String|Object} value An optional value or object to pass in the resolved promise
|
|
* @returns {Promise} A promise that resolves when assetsCache[semaphor] is true
|
|
*/
|
|
function wait(semaphor, value) {
|
|
var p = Q.Promise(function (resolve) {
|
|
setTimeout(function awaitCache() {
|
|
if (assetsCache[semaphor]) {
|
|
return resolve(value);
|
|
}
|
|
setTimeout(awaitCache, 300);
|
|
}, 0);
|
|
});
|
|
return p;
|
|
}
|
|
|
|
// Alternative, less compact implementation?
|
|
// function wait(semaphor, value) {
|
|
// return new Promise(function(resolve){
|
|
// var timer;
|
|
// function awaitCache() {
|
|
// clearTimeout(timer);
|
|
// if (assetsCache[semaphor]) {
|
|
// return resolve(value);
|
|
// } else {
|
|
// timer = setTimeout(awaitCache, 300);
|
|
// }
|
|
// }
|
|
// awaitCache();
|
|
// });
|
|
// }
|
|
|
|
/**
|
|
* Functions and classes exposed by this module
|
|
*/
|
|
return {
|
|
test: test,
|
|
count: count,
|
|
idxDB: idxDB,
|
|
setArticle: setArticle,
|
|
getArticle: getArticle,
|
|
setItem: setItem,
|
|
getItem: getItem,
|
|
clear: clear,
|
|
wait: wait,
|
|
getItemFromCacheOrZIM: getItemFromCacheOrZIM,
|
|
replaceAssetRefsWithUri: replaceAssetRefsWithUri,
|
|
verifyPermission: verifyPermission
|
|
};
|
|
}); |