[Bug]: Upgrade from 29.0.4 to 29.0.6 fails with TypeError in AppFetcher.php

[Derkades]

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

Should the "occ upgrade" command be executed? [Y/n] y
Nextcloud or one of the apps require upgrade - only a limited number of commands are available
You may use your browser or the occ upgrade command to do the upgrade
Setting log level to debug
Repair step: Repair MySQL collation
Repair info: All tables already have the correct collation -> nothing to do
Repair step: Copy data from accounts table when migrating from ownCloud
Repair step: Drop account terms table when migrating from ownCloud
Updating database schema
Updated database
An unhandled exception has been thrown:
TypeError: array_filter(): Argument #1 ($array) must be of type array, null given in /var/www/html/lib/private/App/AppStore/Fetcher/AppFetcher.php:160
Stack trace:
#0 /var/www/html/lib/private/App/AppStore/Fetcher/AppFetcher.php(160): array_filter(NULL)
#1 /var/www/html/lib/private/App/AppStore/Fetcher/Fetcher.php(182): OC\App\AppStore\Fetcher\AppFetcher->fetch('', '', false)
#2 /var/www/html/lib/private/App/AppStore/Fetcher/AppFetcher.php(179): OC\App\AppStore\Fetcher\Fetcher->get(false)
#3 /var/www/html/lib/private/Installer.php(405): OC\App\AppStore\Fetcher\AppFetcher->get(false)
#4 /var/www/html/lib/private/Updater.php(415): OC\Installer->isUpdateAvailable('calendar')
#5 /var/www/html/lib/private/Updater.php(275): OC\Updater->upgradeAppStoreApps(Array)
#6 /var/www/html/lib/private/Updater.php(133): OC\Updater->doUpgrade('29.0.6.1', '29.0.4.1')
#7 /var/www/html/core/Command/Upgrade.php(216): OC\Updater->upgrade()
#8 /var/www/html/3rdparty/symfony/console/Command/Command.php(298): OC\Core\Command\Upgrade->execute(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#9 /var/www/html/3rdparty/symfony/console/Application.php(1040): Symfony\Component\Console\Command\Command->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#10 /var/www/html/3rdparty/symfony/console/Application.php(301): Symfony\Component\Console\Application->doRunCommand(Object(OC\Core\Command\Upgrade), Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#11 /var/www/html/3rdparty/symfony/console/Application.php(171): Symfony\Component\Console\Application->doRun(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#12 /var/www/html/lib/private/Console/Application.php(213): Symfony\Component\Console\Application->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#13 /var/www/html/console.php(102): OC\Console\Application->run()
#14 /var/www/html/occ(11): require_once('/var/www/html/c...')
#15 {main}

Looking at the source code, this happens because the app store server is not returning the expected data. Are there issues with the app store currently?

Steps to reproduce

Run occ upgrade

Expected behavior

N/A

Nextcloud Server version

29

Operating system

None

PHP engine version

None

Web server

None

Database engine version

None

Is this bug present after an update or on a fresh install?

None

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

No response

List of activated Apps

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response

[creopard]

The server error also occurs when opening the "Apps" menue manually while being logged in (although the upgrade from 29.0.5 to 29.0.6 was successful beforehand).

[susnux]

The app store was down due to maintenance from 14:00 until 16:00 MESZ. So this was expected but the error should have been handled more gracefully.

[Derkades]

Alright, it would be nice if starting an upgrade while the app store is down wouldn't result in an unusable instance