Rework dist process and add minimal documentation

[silvanocerza]

I reworked a bit the DistTasks.yml to make it project agnostic as much as possible.

The VERSION var can now be either nightly if the NIGHTLY env var is set to true, a Git tag if NIGHTLY is not set and a tag is found in the current commit, else snapshot is used. Ideally the last case handles a build done locally when checked out at an untagged commit. This change is also reflected in the nightly.yml workflow.

I added the TIMESTAMP_SHORT back in the checksum filename since that should be always present even in tagged releases. This is the way it is in the CLI right now at least.

[per1234]

I added the TIMESTAMP_SHORT back in the checksum filename since that should be always present even in tagged releases. This is the way it is in the CLI right now at least.

Why is it useful to have a timestamp in addition to the tag? The reason I'm questioning this is because I had the idea that people might want to be able to download the checksums for the releases just as they can currently do with the nightly. But having the timestamp in the filename will make that more difficult than simply being able to insert the version they want into the URL.

[silvanocerza]

Why is it useful to have a timestamp in addition to the tag? The reason I'm questioning this is because I had the idea that people might want to be able to download the checksums for the releases just as they can currently do with the nightly. But having the timestamp in the filename will make that more difficult than simply being able to insert the version they want into the URL.

The CLI checksum file always contains the timestamp so I did the same to keep it compatible, same for nightlies.
At least according to the documentation, I just tried to download it but I can't seem to find the file.
I'd expect https://downloads.arduino.cc/arduino-cli/nightly/nightly-20210101-checksums.txt to work but it doesn't.

[per1234]

The CLI checksum file always contains the timestamp so I did the same to keep it compatible, same for nightlies.

For the nightlies, it definitely makes sense because the timestamp is what we use as the unique identifier of nightlies. But for the releases we already have a unique identifier: the version, so I don't see that the timestamp adds any benefits, while also having a disadvantage.

I think it's good to maintain consistency between arduino-lint and Arduino CLI's infrastructure where possible, but I also see this as an opportunity to have a fresh start and make improvements on Arduino CLI's infrastructure, which can then be ported back to Arduino CLI. Arduino CLI's checksum system is already broken (see below), so it needs to be be changed anyway. That could be done at the same time as this new build system you designed is put in place.

I'd expect https://downloads.arduino.cc/arduino-cli/nightly/nightly-20210101-checksums.txt to work but it doesn't.

See ATL-794

[silvanocerza]

The CLI checksum file always contains the timestamp so I did the same to keep it compatible, same for nightlies.

For the nightlies, it definitely makes sense because the timestamp is what we use as the unique identifier of nightlies. But for the releases we already have a unique identifier: the version, so I don't see that the timestamp adds any benefits, while also having a disadvantage.

I think it's good to maintain consistency between arduino-lint and Arduino CLI's infrastructure where possible, but I also see this as an opportunity to have a fresh start and make improvements on Arduino CLI's infrastructure, which can then be ported back to Arduino CLI. Arduino CLI's checksum system is already broken (see below), so it needs to be be changed anyway. That could be done at the same time as this new build system you designed is put in place.

I'd expect https://downloads.arduino.cc/arduino-cli/nightly/nightly-20210101-checksums.txt to work but it doesn't.

See ATL-794

Aha! Didn't know it was broken for the CLI, am all in to change it then.

[per1234]

I ran the nightly and release workflows in my fork and everything worked perfectly. Great work Silvano!