From 0ea5d01062a8c47dd5373e8f3478195dd2531639 Mon Sep 17 00:00:00 2001
From: Franco Montenegro <franco.montenegro.ruke@gmail.com>
Date: Fri, 4 Mar 2022 12:01:08 -0300
Subject: [PATCH] Allow to properly cancel download upgrade and prevent
 multiple downloads.

---
 electron/index.js         | 36 +++++++++++++++++++++++++++---------
 ui/redux/actions/app.js   | 22 ++--------------------
 ui/redux/selectors/app.js |  2 --
 3 files changed, 29 insertions(+), 31 deletions(-)

diff --git a/electron/index.js b/electron/index.js
index 68ee2c946..b7143b87a 100644
--- a/electron/index.js
+++ b/electron/index.js
@@ -51,11 +51,9 @@ let showingAutoUpdateCloseAlert = false;
 // https://www.electronjs.org/docs/latest/api/auto-updater#autoupdatercheckforupdates
 let keepCheckingForUpdates = true;
 
-// Auto updater doesn't support Linux installations (only trough AppImages)
-// this is why, for that case, we download a full executable (.deb package)
-// as a fallback support. This variable will be used to prevent
-// multiple downloads when auto updater isn't supported.
-let downloadUpgradeInProgress = false;
+let downloadUpgradeInitiated = false;
+
+let downloadUpgradeItem;
 
 // Keep a global reference, if you don't, they will be closed automatically when the JavaScript
 // object is garbage collected.
@@ -328,23 +326,43 @@ ipcMain.on('get-disk-space', async (event) => {
   }
 });
 
+ipcMain.on('cancel-download-upgrade', () => {
+  if (downloadUpgradeItem) {
+    // Cancel the download and execute the onCancel
+    // callback set in the options.
+    downloadUpgradeItem.cancel();
+  }
+});
+
 ipcMain.on('download-upgrade', async (event, params) => {
-  if (downloadUpgradeInProgress) {
+  // Prevent downloading multiple times.
+  if (downloadUpgradeInitiated || downloadUpgradeItem) {
     return;
   }
-
   const { url, options } = params;
   const dir = fs.mkdtempSync(app.getPath('temp') + path.sep);
+
+  downloadUpgradeInitiated = true;
+
+  // Grab the download item's handler to allow
+  // cancelling the operation if required.
+  options.onStarted = function(downloadItem) {
+    downloadUpgradeItem = downloadItem;
+  };
+  options.onCancel = function() {
+    downloadUpgradeItem = undefined;
+    downloadUpgradeInitiated = false;
+  };
   options.onProgress = function(p) {
     rendererWindow.webContents.send('download-progress-update', p);
   };
   options.directory = dir;
   options.onCompleted = function(c) {
-    downloadUpgradeInProgress = false;
+    downloadUpgradeInitiated = false;
+    downloadUpgradeItem = undefined;
     rendererWindow.webContents.send('download-update-complete', c);
   };
   const win = BrowserWindow.getFocusedWindow();
-  downloadUpgradeInProgress = true;
   await download(win, url, options).catch(e => console.log('e', e));
 });
 
diff --git a/ui/redux/actions/app.js b/ui/redux/actions/app.js
index a431a7352..f8916d36e 100644
--- a/ui/redux/actions/app.js
+++ b/ui/redux/actions/app.js
@@ -28,7 +28,6 @@ import {
 import {
   selectIsUpgradeSkipped,
   selectUpdateUrl,
-  selectUpgradeDownloadItem,
   selectUpgradeDownloadPath,
   selectAutoUpdateDeclined,
   selectRemoteVersion,
@@ -163,25 +162,8 @@ export function doAutoUpdateDeclined() {
 }
 
 export function doCancelUpgrade() {
-  return (dispatch, getState) => {
-    const state = getState();
-    const upgradeDownloadItem = selectUpgradeDownloadItem(state);
-
-    if (upgradeDownloadItem) {
-      /*
-       * Right now the remote reference to the download item gets garbage collected as soon as the
-       * the download is over (maybe even earlier), so trying to cancel a finished download may
-       * throw an error.
-       */
-      try {
-        upgradeDownloadItem.cancel();
-      } catch (err) {
-        console.error(err); // eslint-disable-line no-console
-      }
-    }
-
-    dispatch({ type: ACTIONS.UPGRADE_CANCELLED });
-  };
+  ipcRenderer.send('cancel-download-upgrade');
+  return { type: ACTIONS.UPGRADE_CANCELLED };
 }
 
 export function doCheckUpgradeAvailable() {
diff --git a/ui/redux/selectors/app.js b/ui/redux/selectors/app.js
index c2e65de7d..920267b62 100644
--- a/ui/redux/selectors/app.js
+++ b/ui/redux/selectors/app.js
@@ -50,8 +50,6 @@ export const selectIsUpgradeSkipped = createSelector(selectState, (state) => sta
 
 export const selectUpgradeDownloadPath = createSelector(selectState, (state) => state.downloadPath);
 
-export const selectUpgradeDownloadItem = createSelector(selectState, (state) => state.downloadItem);
-
 export const selectAutoUpdateDownloaded = createSelector(selectState, (state) => state.autoUpdateDownloaded);
 
 export const selectAutoUpdateDeclined = createSelector(selectState, (state) => state.autoUpdateDeclined);