Test pineline in Ubuntu 20.04 and Cent OS 7/8/9

[scarlehoff]

For the school we are going to get a lot of people with access to only one of those systems. We need to make sure that it works and when it doesn't, have a quick workaround ready.

The docker image is fine but docker is not always available.

I know Ubuntu 20.04 is old, but turns out a lot of people is still using it.

(I'm trying my best to avoid conda!)

Also, I didn't put it in the title of the issue but I want to try to create a bottle for homebrew.

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For Ubuntu 20.04

The easiest solution (the one that works out of the box) is to use the deadsnakes ppa and install from there python 3.10

add-apt-repository ppa:deadsnakes/ppa
apt update
apt install python3.10-full python3.10-dev
poetry env use python3.10

Note: it might also work with python3.10-minimal but I didn't try.

Installing python by hand also works but then you have to make sure that everything is in the right place so no longer out of the box (almost though, only lz4 was a problem). I'll try to put it nicely as a script than can be copied and pasted since it would also work in other systems.

[alecandido]

Nope, Ubuntu 20.04 is still supported and perfectly fine. Actually, in principle even 18.04 is still supported, but it will be dropped next year, and I don't have time enough to support also that one...

As said in #10, 3.10 was only the default, and it was a mistake to keep, I can easily lower to 3.8, and I will do it (3.7 is a bit more uncomfortable, because I should re-enable EKO tests, potentially breaking, re-release it, and on top of an older release, since the current one is not yet fully compatible...).

[scarlehoff]

tbh, python3.9 would already be a big difference

3.8 helps because that makes it compatible also with centos 8 (at least the one in the cern cluster) without having to use any of the views. It's also the default for Ubuntu actually. 3.9 needs to be installed from universe.

3.7 I'm ok with dropping, none of the computers have only 3.7.