Updater

createUpdater puts electron-updater behind a state the page watches instead of a dialog that interrupts. Every change goes to publish as an UpdateState, which the page draws as a button or a line in its About pane.

import { createUpdater } from '@adecore/shell';

const updater = createUpdater({
    currentVersion: app.getVersion(),
    packaged: app.isPackaged,
    load: () => require('electron-updater').autoUpdater,
    publish: (state) => window.webContents.send('update:state', state)
});

app.whenReady().then(() => updater.start());

handleFromApp('update:state', () => updater.state());
handleFromApp('update:configure', (_event, autoDownload: unknown) => updater.configure(autoDownload));
handleFromApp('update:check', () => updater.check());
handleFromApp('update:download', () => updater.download());
onFromApp('update:install', () => updater.install());

States

status	Means
unsupported	A checkout. electron-updater reads its feed from the bundle, so there is none.
idle	Started, nothing checked yet.
checking	A check runs.
current	The check found nothing newer.
available	version is newer and not downloaded.
downloading	percent of it is in.
ready	Downloaded; install restarts into it.
error	error says why, in one line.

Who decides to download

The page owns the preference. Nothing downloads and no timer runs until the page sends it with configure; from then on the updater checks once an hour. Only true turns downloading on. A check is skipped while one runs, while a download runs and once a build is ready.

beforeCheck runs right before a check asks the feed, such as to refresh release notes along with it.

Installing

install() quits into the downloaded build and answers whether it did: without a build that is ready it does nothing. electron-updater closes the windows before the app's own before-quit runs, so onQuit(true) comes right before the install, and onQuit(false) when the install fails and the app stays. With a set of windows that is where the session learns about the quit:

const updater = createUpdater({
    // ...
    onQuit: (quitting) => (quitting ? windows.quit() : windows.resume())
});

Errors

electron-updater puts the whole HTTP exchange in the message of a failed check, cookies included. describeUpdateError keeps the first line only, and turns a 404 on the feed into a sentence that says there is no published release, or that the repository is private.