Initial Typescripting for Element Desktop

src/updater.ts

@@ -0,0 +1,122 @@
+/*
+Copyright 2016-2021 New Vector Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { app, autoUpdater, ipcMain } from "electron";
+
+const UPDATE_POLL_INTERVAL_MS = 60 * 60 * 1000;
+const INITIAL_UPDATE_DELAY_MS = 30 * 1000;
+
+function installUpdate(): void {
+    // for some reason, quitAndInstall does not fire the
+    // before-quit event, so we need to set the flag here.
+    global.appQuitting = true;
+    autoUpdater.quitAndInstall();
+}
+
+function pollForUpdates(): void {
+    try {
+        autoUpdater.checkForUpdates();
+    } catch (e) {
+        console.log('Couldn\'t check for update', e);
+    }
+}
+
+export function start(updateBaseUrl: string): void {
+    if (updateBaseUrl.slice(-1) !== '/') {
+        updateBaseUrl = updateBaseUrl + '/';
+    }
+    try {
+        let url;
+        // For reasons best known to Squirrel, the way it checks for updates
+        // is completely different between macOS and windows. On macOS, it
+        // hits a URL that either gives it a 200 with some json or
+        // 204 No Content. On windows it takes a base path and looks for
+        // files under that path.
+        if (process.platform === 'darwin') {
+            // include the current version in the URL we hit. Electron doesn't add
+            // it anywhere (apart from the User-Agent) so it's up to us. We could
+            // (and previously did) just use the User-Agent, but this doesn't
+            // rely on NSURLConnection setting the User-Agent to what we expect,
+            // and also acts as a convenient cache-buster to ensure that when the
+            // app updates it always gets a fresh value to avoid update-looping.
+            url = `${updateBaseUrl}macos/${process.arch}/?localVersion=${encodeURIComponent(app.getVersion())}`;
+        } else if (process.platform === 'win32') {
+            url = `${updateBaseUrl}win32/${process.arch}/`;
+        } else {
+            // Squirrel / electron only supports auto-update on these two platforms.
+            // I'm not even going to try to guess which feed style they'd use if they
+            // implemented it on Linux, or if it would be different again.
+            console.log('Auto update not supported on this platform');
+        }
+
+        if (url) {
+            console.log(`Update URL: ${url}`);
+            autoUpdater.setFeedURL(url);
+            // We check for updates ourselves rather than using 'updater' because we need to
+            // do it in the main process (and we don't really need to check every 10 minutes:
+            // every hour should be just fine for a desktop app)
+            // However, we still let the main window listen for the update events.
+            // We also wait a short time before checking for updates the first time because
+            // of squirrel on windows and it taking a small amount of time to release a
+            // lock file.
+            setTimeout(pollForUpdates, INITIAL_UPDATE_DELAY_MS);
+            setInterval(pollForUpdates, UPDATE_POLL_INTERVAL_MS);
+        }
+    } catch (err) {
+        // will fail if running in debug mode
+        console.log('Couldn\'t enable update checking', err);
+    }
+}
+
+ipcMain.on('install_update', installUpdate);
+ipcMain.on('check_updates', pollForUpdates);
+
+function ipcChannelSendUpdateStatus(status: boolean | string): void {
+    if (!global.mainWindow) return;
+    global.mainWindow.webContents.send('check_updates', status);
+}
+
+interface ICachedUpdate {
+    releaseNotes: string;
+    releaseName: string;
+    releaseDate: Date;
+    updateURL : string;
+}
+
+// cache the latest update which has been downloaded as electron offers no api to read it
+let latestUpdateDownloaded: ICachedUpdate;
+autoUpdater.on('update-available', function() {
+    ipcChannelSendUpdateStatus(true);
+}).on('update-not-available', function() {
+    if (latestUpdateDownloaded) {
+        // the only time we will get `update-not-available` if `latestUpdateDownloaded` is already set
+        // is if the user used the Manual Update check and there is no update newer than the one we
+        // have downloaded, so show it to them as the latest again.
+        if (!global.mainWindow) return;
+        global.mainWindow.webContents.send('update-downloaded', latestUpdateDownloaded);
+    } else {
+        ipcChannelSendUpdateStatus(false);
+    }
+}).on('error', function(error) {
+    ipcChannelSendUpdateStatus(error.message);
+});
+
+autoUpdater.on('update-downloaded', (ev, releaseNotes, releaseName, releaseDate, updateURL) => {
+    if (!global.mainWindow) return;
+    // forward to renderer
+    latestUpdateDownloaded = { releaseNotes, releaseName, releaseDate, updateURL };
+    global.mainWindow.webContents.send('update-downloaded', latestUpdateDownloaded);
+});