Best approach for scheduling update checks (and installation) even if hostBundle is not running

[Davack]

Hey everyone,
I've been using Sparkle for some time, and I love it!
There is one scenario where I don't find any formal solution within Sparkle.
I want all my clients to check for updates in a scheduled manner (let's say once a day) and will download & install updates if found. This way, my clients will be much more up-to-date when launching my app.

The solutions I came up with:

1. Create a launch daemon agent that uses Sparkle with initWithHost: myAppHost and check for updates every once in a while.
2. Sending XPC message to trigger Sparkle update.

I will be glad to both hear your ideas and receive your feedback. Thanks a lot!

[zorgiepoo]

[edit: this is not a common solution. See below answer for what most apps do and what we recommend them to do]

I am assuming the app you are updating still belongs to you, just that you want to update it from another process that also belongs to you, if the app is not running (this "belongs to you" point is important).

Using sparkle-cli, is what you want similar to:

# This lets sparkle schedule update checks automatically (provided it has been granted permission). You can add --check-immediately if you don't want this and want to force a check.
./sparkle bundle-path --defer-install

I'm not saying you have to use sparkle-cli (which just wraps around Sparkle's framework with a minimal UI) but we can start discussion there. --defer-install updates the app immediately if the app isn't running otherwise it updates the app after it terminates, in which case Sparkle's tools (Autoupdate / Updater.app) are spawned and handles that.

You also need to tackle potential user authorization case when users don't have sufficient permission to install an app without authorizing (for example a standard user updating an app in /Applications/ owned by admin). You can let Sparkle ask for authorization in such cases (denoted by --interactive in sparkle-cli), or have your daemon authorize beforehand and run Sparkle's updater under root (which is supported recently now in 2.2.0 betas as long as you don't use AppKit and don't have any GUI).

[Davack]

Actually, this wraps up my question. Thanks a lot!

[zorgiepoo]

If you do go a route of an external updater, be sure the external updater and the bundle being updated are Apple code signed with the same identity.

[zorgiepoo]

The above answer I wrote might be overthinking it..

What most apps do for automatically installing updates is use SUAutomaticallyUpdate described here. When the app is running, updates are downloaded silently and installed on quit when possible. Did you already look at that?