How to perform update check on application startup and wait for user to respond

[duncangroenewald]

I need to check for software updates immediately on starting the application and need to prevent the application from performing other startup activities until the user has responded if there were any updates.

It's not clear whether there is a way to programatically control the checking via APIs.

PSUEDO CODE

1. App Starts
2. Perform Sparkle Check silently
3. If Update available prompt user and wait for user input, otherwise continue
4. Perform next startup steps...

Thanks

[duncangroenewald]

OK, I found it - use the updater to programatically control the checking.

[zorgiepoo]

Note this can lead to a bad user experience. Performing a background check via checkForUpdatesInBackground could have some latency, so if you treat it in a synchronous way you may add latency to your app launch experience. Also as the documentation states for that method, by default Sparkle may not deliver the update alert immediately if a significant amount of time elapses after starting the updater. There's also automatic downloading of updates via SUAutomaticallyUpdate to consider.

[duncangroenewald]

Note this can lead to a bad user experience. Performing a background check via checkForUpdatesInBackground could have some latency, so if you treat it in a synchronous way you may add latency to your app launch experience. Also as the documentation states for that method, by default Sparkle may not deliver the update alert immediately if a significant amount of time elapses after starting the updater. There's also automatic downloading of updates via SUAutomaticallyUpdate to consider.

Not sure what you mean - as there is this in the documentation.

After starting the updater and before the next runloop cycle, one of -checkForUpdates, -checkForUpdatesInBackground, or -checkForUpdateInformation can be invoked. This may be useful if you want to check for updates immediately or without showing a potential permission prompt.

So far this seems to do the check instantly.

I am not using any automatic Sparkle options and have my own Timer in the app to trigger the background checks once the app has started up - so for these it doesn't matter if there is a delay before getting a response - but I don't see any delay.

As for bad user experience - it doesn't get any worse than when using the Standard Sparkle controller.

What is the relevance of SUAutomaticallyUpdate ?

[zorgiepoo]

Initiating a background update check via checkForUpdatesInBackground when your app starts is not bad in of itself.

What may be bad is if you expect this check to always return instantly or block other behaviors of your app until this check completes and a potential update alert shows up. And that's what I gathered when you said:

...need to prevent the application from performing other startup activities until the user has responded if there were any updates.

3. If Update available prompt user and wait for user input, otherwise continue
4. Perform next startup steps...

Hypothetically speaking, if it does take say 7 seconds to request the feed from your server after starting the updater for whatever network-related reason, by default Sparkle's standard UI may not show the update alert immediately and may show it at a more opportune time.

The SPUStandardUpdaterController gives you access to the SPUUpdater. Creating your own SPUUpdater directly only gives you more flexibility here if you want a custom user interface, which might be a relevant option -- for example if you want to visibly show checking for updates (via checkForUpdates) and automatically trying to update before proceeding to other startup steps.

What is the relevance of SUAutomaticallyUpdate ?

This option is for silently (when possible) installing updates in the background on app quit. As such, a checkForUpdatesInBackground call may not show an update alert but rather download/install the update later in the background. Set SUAllowsAutomaticUpdates if you don't want users to opt into this.