Do not update package cache on install/upgrade

[DL6ER]

What does this implement/fix?

Do not update package cache on install/upgrade. It takes quite a long time and we don't do this for dnf/yum either.

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Related issue or feature (if applicable): N/A

Pull request in docs with documentation (if applicable): N/A

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[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/pihole-up-skip-package-update/66512/15

[yubiuser]

Do we wan to keep notify_package_updates_available()?

[DL6ER]

No, I think this is only due to the artificially clean environment of a CI container. No real OS will know nothing about their sources. We neither support installing into naked container (or do we?).

If we do, the logic needs to be changed to use apt-cache to check if we have install candidates for packages and, if not, then indeed run apt update.

Converting this PR to draft and doing this later...

[yubiuser]

This is not a good place to put the update function. It will update the cache 3 times in a row on new installs as install_dependent_packages() is called 3 times during installation and usually not empty.

[DL6ER]

@yubiuser I simplified the approach

[PromoFaux]

I'm a little confused as to the logic here...

PKG_MANAGER_UPDATE is defaulted to false. once update_package_cache runs, it is set to true and so subsequent calls of this function will not do the package update.

What I can't see here is how we get ourselves into a situation where update_package_cache is run more than once... Sure, it would run each time one runs pihole -up... but each time that is run the value of PKG_MANAGER_UPDATE will be false... and therefore the update_package_cache function will run in full.

Maybe I'm just being dense... but what is the goal here?

[DL6ER]

I think this PR has been changed too often and it was abandoned too often, too, to reproduce its original intention. Closing.