APT purge available packages even when some package is not available

To the point

Needles to say that:

1. Purging hundreds of installed packages at once is a bad idea regardless of the reason for that.

2. Using APT's option -y to automatically answer yes, is even a worse idea.

You probably know that, but I had to note it ... On to your question:

AFAIK APT can't do that ... APT does more than the basic actions of just attempt to install, remove, purge ... etc. ... It resolves dependencies, avoids and warns about conflicts, substitutes some removed packages ... etc. ... Thus it has to parse/check all passed packages against its cached available packages database before it begins committing any user specified action on them.

Therefore, your best bet in that situation is to pass those packages one at a time to APT using xargs like:

echo "pack1 pack2 pack3" | xargs -n 1 apt purge

or using a shell loop like:

for p in "pack1" "pack2" "pack3"
  do
    apt purge "$p"
    done

or similar solutions.

On the other hand, if using APT is not a must for you, then dpkg should do the job without exiting on such packages "Unable to locate packages" and can be used like so:

dpkg --purge pack1 pack2 pack3

Around the point

Demonstration:

$ apt -s purge -y vlc golang
NOTE: This is only a simulation!
      apt needs root privileges for real execution.
      Keep also in mind that locking is deactivated,
      so don't depend on the relevance to the real current situation!
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Package 'golang' is not installed, so not removed
The following packages will be REMOVED:
  vlc*
0 to upgrade, 0 to newly install, 1 to remove and 5 not to upgrade.
Purg vlc [3.0.16-1build7]

Notice the three steps before committing the purge action:

Reading package lists... Done
Building dependency tree... Done
Reading state information... Done

These are self explanatory and although the package golang is not installed:

Package 'golang' is not installed, ...

But, APT could locate it in its cached packages list and thus could take a decision regarding it:

... so not removed 

and:

The following packages will be REMOVED:
  vlc*
...

That is normal and APT will carry on removing the installed package/s

But in case of a package that APT can't locate in its cached packages lists:

$ apt -s purge -y vlc non-locatable-package
NOTE: This is only a simulation!
      apt needs root privileges for real execution.
      Keep also in mind that locking is deactivated,
      so don't depend on the relevance to the real current situation!
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
E: Unable to locate package non-locatable-package

APT can't take the decision and thus exits after printing an error:

E: Unable to locate package non-locatable-package

Important notice:

As seen in the demonstration above, APT checks its cached packages lists obtained via the update action and therefore, an up to date packages list/s is vital to correct functionality of APT and doing purge/remove or even install actions with an outdated packages list/s might result in an unexpected result removing unintended packages ... See for example apt-get install unexpectedly removed Firefox ... Therefore, make sure the packages list/s are up to date by running:

sudo apt update

first.

The apt purge command will fail if any of the packages you specify do not exist. This is because apt purge removes all of the files associated with a package, including configuration files. If a package does not exist, then there are no files to remove, so the apt purge command fails.

To force the purge of existing installed packages, even if one of the packages does not exist, you can use the --force-remove option. For example, the following command will purge the packages pack1, pack2, and pack3, even if pack3 does not exist:

sudo apt purge --force-remove pack1 pack2 pack3

The --force-remove option tells apt purge to ignore any errors that occur when it tries to remove a package that does not exist. This means that the apt purge command will still succeed, even if one of the packages you specify does not exist.

Here is a breakdown of the command:

• sudo - This tells the command to be run as root.
• apt purge - This is the command to purge a package.
• --force-remove - This option tells apt purge to ignore any errors that occur when it tries to remove a package that does not exist.
• pack1 pack2 pack3 - These are the packages that you want to purge.

If you're facing the issue where the entire process fails due to a missing package while attempting to apt purge or remove multiple packages at once, there is a way to ensure the removal of the existing installed packages without being hindered by the absence of a single package.

To accomplish this, you can make use of a bash command called "apt-get --ignore-missing". This command allows you to continue with the removal process even if some packages are not found.

Here's an example of how you can modify your GitHub action step to include this command:

sudo apt-get --ignore-missing purge pack1 pack2 pack3 -y

By using the "--ignore-missing" flag, apt-get will disregard any packages that it cannot find and proceed with purging the remaining packages. This ensures that pack1 and pack2, if present, will still be purged even if pack3 is not found.

This way, you can confidently purge the existing installed packages without the process failing due to the absence of a single package.

Hope this solution helps you achieve the desired outcome in your GitHub action!