Delete deprecated idxDB databases if possible

Former-commit-id: 1f27164b9fb5f9674a081c6ea1f783b6f79a41fc [formerly 1fe9a54a409fd9c7fce2eff03aac496dfb2846ed [formerly 617fac3bd55b852f18d0b0135e29ebf1b3dbafe4]]
Former-commit-id: 31426d4308472b82aa9fa9aee836fec0a2ace6c6
Former-commit-id: b1957276bedcd17227f16c1422ca4c87c0b328fd

pwabuilder-sw.js

@@ -4,7 +4,7 @@
 // App version number - ENSURE IT MATCHES VALUE IN init.js
 // DEV: Changing this will cause the browser to recognize that the Service Worker has changed, and it will download and
 // install a new copy
-const appVersion = '1.1.4-RP5';
+const appVersion = '1.1.4-RP6';
 
 // Kiwix ZIM Archive Download Server in regex form
 // DEV: The server URL is defined in init.js, but is not available to us in SW

www/index.html

@@ -529,7 +529,7 @@
                                     <table>
                                         <tr>
                                             <td><input style="float:left; margin-right:1em;" type="button" class="btn btn-primary" value="Select storage" id="btnRescanDeviceStorage" /></td>
-                                            <td style="width:100%;">Tap to select app's local storage or to select a file or folder</td>
+                                            <td style="width:100%;">Tap to select app's local storage or to select a file or folder. <b>You can also drag and drop a ZIM file into the app.</b></td>
                                         </tr>
                                     </table>
                                 </div>

www/js/app.js

@@ -1368,12 +1368,20 @@ define(['jquery', 'zimArchiveLoader', 'uiUtil', 'util', 'cache', 'images', 'sett
             //Code below triggers display of modal info box if app is run for the first time, or it has been upgraded to new version
             if (settingsStore.getItem('version') !== params.version) {
                 firstRun = true;
-                // Make user re-pick file if we have upgraded (it's less confusing than filehandle errors)
+                
-                settingsStore.removeItem('listOfArchives');
+                // Make user re-pick file if we have upgraded (it's less confusing than filehandle errors) - NOT NEEDED, remove in due course
+                // settingsStore.removeItem('listOfArchives');
+
+                //  Update the installed version
                 if (params.PWAInstalled) {
                     params.PWAInstalled = params.version;
                     settingsStore.setItem('PWAInstalled', params.PWAInstalled);
-                } 
+                }
+                // One-time cleanup of idxDB files to delete deprecated databases if possible
+                cache.idxDB('deleteNonCurrent', function (result) {
+                    if (result === false) console.log('Unable to delete old idxDB databases (this is normal in non-Chromium browsers');
+                    else console.log('Deleted ' + result + ' deprecated database(s).');
+                });
                 // On some platforms, bootstrap's jQuery functions have not been injected yet, so we have to run in a timeout
                 setTimeout(function () {
                     $('#myModal').modal({

www/js/init.js

@@ -49,7 +49,7 @@ var params = {};
  */
 var appstate = {};
 /******** UPDATE VERSION IN pwabuilder-sw.js TO MATCH VERSION *******/
-params['version'] = "1.1.4-RP5"; //DEV: Manually update this version when there is a new release: it is compared to the Settings Store "version" in order to show first-time info, and the cookie is updated in app.js
+params['version'] = "1.1.4-RP6"; //DEV: Manually update this version when there is a new release: it is compared to the Settings Store "version" in order to show first-time info, and the cookie is updated in app.js
 /******* UPDATE THIS ^^^^^^ IN serveice worker!! ********************/
 params['packagedFile'] = "wikipedia_en_100_maxi.zim"; //For packaged Kiwix JS (e.g. with Wikivoyage file), set this to the filename (for split files, give the first chunk *.zimaa) and place file(s) in default storage
 params['archivePath'] = "archives"; //The directory containing the packaged archive(s) (relative to app's root directory)  

www/js/lib/cache.js

@@ -23,7 +23,8 @@
 'use strict';
 define(['q', 'settingsStore', 'uiUtil'], function(Q, settingsStore, uiUtil) {
 
-    const CACHE = 'kiwix-precache-' + params.version; // Set the database or cache name here
+    const CACHEAPI = 'kiwix-precache-' + params.version; // Set the database or cache name here
+    const CACHEIDB = 'kiwix-assetsCache'; // For idxDB we don't want the name to change
     var objStore = 'kiwix-assets'; // Name of the object store
     
     // DEV: Regex below defines the permitted key types for the cache; add further types as needed
@@ -111,7 +112,7 @@ define(['q', 'settingsStore', 'uiUtil'], function(Q, settingsStore, uiUtil) {
                 case 'cacheAPI':
                     type = 'cacheAPI';
                     description = 'CacheAPI';
-                    caches.open(CACHE).then(function (cache) {
+                    caches.open(CACHEAPI).then(function (cache) {
                         cache.keys().then(function (keys) {
                             callback({'type': type, 'description': description, 'count': keys.length});
                         });
@@ -134,7 +135,8 @@ define(['q', 'settingsStore', 'uiUtil'], function(Q, settingsStore, uiUtil) {
      * on the database
      * 
      * @param {String} keyOrCommand The key of the value to be written or read, or commands 'clear' (clears objStore),
-     *     'count' (counts number of objects in objStore), 'delete' (deletes a record with key passed in valueOrCallback)         
+     *     'count' (counts number of objects in objStore), 'delete' (deletes a record with key passed in valueOrCallback),
+     *      'deleteNonCurrent' (deletes all databases that do not match CACHEIDB - but only works in Chromium currently)         
      * @param {Variable} valueOrCallback The value to write, or a callback function for read and command transactions
      * @param {Function} callback Callback for write transactions only
      */
@@ -145,9 +147,29 @@ define(['q', 'settingsStore', 'uiUtil'], function(Q, settingsStore, uiUtil) {
             rtnFn(false);
             return;
         } 
+
+        // Delete all non-curren IdxDB databases (only works in Chromium currently)
+        if (keyOrCommand === 'deleteNonCurrent') {
+            if (indexedDB.databases) {
+                var result = 0;
+                indexedDB.databases().then(function (dbs) {
+                    dbs.forEach(function (db) {
+                        if (db.name !== CACHEIDB) {
+                            result++;
+                            indexedDB.deleteDatabase(db.name);
+                        }
+                    });
+                }).then(function () {
+                    rtnFn(result);
+                });
+            } else {
+                rtnFn(false);
+            }
+            return;
+        }
         
         // Open (or create) the database
-        var open = indexedDB.open(CACHE, 1);
+        var open = indexedDB.open(CACHEIDB, 1);
 
         open.onerror = function(e) {
             // Suppress error reporting if testing (older versions of Firefox support indexedDB but cannot use it with
@@ -222,14 +244,14 @@ define(['q', 'settingsStore', 'uiUtil'], function(Q, settingsStore, uiUtil) {
         var rtnFn = callback || valueOrCallback;
         // Process commands
         if (keyOrCommand === 'clear') {
-            caches.delete(CACHE).then(rtnFn);
+            caches.delete(CACHEAPI).then(rtnFn);
         } else if (keyOrCommand === 'delete') {
-            caches.open(CACHE).then(function(cache) {
+            caches.open(CACHEAPI).then(function(cache) {
                 cache.delete(value).then(rtnFn);
             });
         } else if (value === null) {
             // Request retrieval of data
-            caches.open(CACHE).then(function(cache) {
+            caches.open(CACHEAPI).then(function(cache) {
                 cache.match('../' + keyOrCommand).then(function(response) {
                     if (!response) {
                         rtnFn(null);
@@ -245,7 +267,7 @@ define(['q', 'settingsStore', 'uiUtil'], function(Q, settingsStore, uiUtil) {
             });
         } else {
             // Request storing of data in cache
-            caches.open(CACHE).then(function(cache) {
+            caches.open(CACHEAPI).then(function(cache) {
                 // Construct a Response from value
                 var response = new Response(value);
                 cache.put('../' + keyOrCommand, response).then(function() {