Auto update tool for macOS screensaver Aerial (v2+)

AerialUpdater

The official install/auto-update tool for the Aerial screen saver for macOS.

As the name implies, this utility will install Aerial's latest versions on your system and keep you up to date.

Installation

Download the latest release, unzip and copy AerialUpdater.app to /Applications (or some other place of your choice, then double-click to launch.

To uninstall, simply delete AerialUpdater.app.

I thought Aerial had auto-updates already ?

Aerial had auto-updates starting with version 1.5.0, this feature was provided by the Sparkle framework.

With the introduction of macOS 10.15 (Catalina), things changed for screen savers and Aerial was no longer able to update itself because of the new security restrictions introduced with sandboxing. A temporary workaround was put in place in version 1.8.0 where you could get notified of a new version.

While this worked most of the time, for some users, the update check caused the ScreenSaverEngine to lose the keyboard/mouse focus, and pressing a key would no longer let you exit the screen saver (pressing cmd-alt-shift-esc would workaround the issue). This issue seem to trigger a lot more often in macOS 11 (Big Sur), so because of this, Sparkle was completely removed from Aerial with version 2.0.0, and this tool was created to replace it.

How does it work ?

You simply pick in the menu which version of Aerial you want to use (you can specify if you just want releases or beta versions too), and whether you want updates to happen automatically in the background, or if you'd rather be notified. If you choose to be notified, the icon will change color and clicking the menu will let you install the new version.

I meant, how does it work technically ?

In this repository, I store a manifest file that contains the version number of the latest release, and also the sha256 of the releases. This is generated after Aerial gets notarized for distribution and before I upload a new version on Aerial's releases page.

Periodically, AerialUpdater checks the manifest to see if a new version was released. When you decide to perform an update, the following happens

AerialUpdater uses the version number from the manifest to infer the download link from Aerial's repository (the download links are always of the same format, so version 1.9.2 will be available at https://github.com/JohnCoates/Aerial/releases/download/v1.9.2/Aerial.saver.zip)
The zip file is downloaded to ~/Library/Application Support/AerialUpdater/
The sha256 of the file is computed, and compared to the one from the manifest
The zip is unzipped in place, looking for Aerial.saver
Aerial.saver is verified (using macOS codesigning) to be using the correct Bundle ID (com.JohnCoates.Aerial)
Aerial.saver is verified (using macOS codesigning) to be signed/notarized with my Developer Apple ID.

If and only if everything checks out, then Aerial.saver gets copied to ~/Library/Screen Savers/.

Do I have to use this ? Is there an alternative ?

You don't, and sure, as pointed out in Aerial's installation instructions, you can also use homebrew if you want automatic updates.

And you can always manually download and install Aerial from its Github repository.

I don't want one more icon on my status bar !

The current version only works as a status bar item, but the option to run it as a daemon will happen in a subsequent release.

Any known caveats/issues with version 0.3

This tool only install/updates Aerial if you install it for your user only, and not for all users. Installing a screen saver for all users require an administrator password at install, and at each subsequent update, defeating the purpose of an auto-updater. It's recommended to check if you have an Aerial.saver file in /Library/Screen Savers/If you do, please remove it as you'll get two versions of Aerial alongside each other in your
Like always when updating a screen saver, you must first close System Preferences. If you don't, you will need to restart it after installation to reload the new version as the old one will remain in memory.