Eliminate predefined prereqs/packages directory

[mthalman]

The prereqs/packages directory of the VMR is essentially empty, containing only some placeholder files. These directories get populated when running the source-build-prep.sh script. This pattern of having predefined directories is awkward and seems unnecessary. In reality, they are really acting like artifacts directories. So it would make more sense to simply replace this to use the artifacts directory.

[mthalman]

I guess the difference here with the artifacts directory is that these packages are considered to be input into the build whereas the artifacts directory is output. Still, it would be nice if there was an alternative way that didn't rely on predefined directories in the repo.

[ViktorHofer]

Agreed, I don't like that either especially as that directory doesn't do anything when not building source-only.

I guess the difference here with the artifacts directory is that these packages are considered to be input into the build whereas the artifacts directory is output. Still, it would be nice if there was an alternative way that didn't rely on predefined directories in the repo.

I wonder why these inputs need to be under the source tree vs any other inputs which are usually supplied via paths pointing to any location on the machine.

[mthalman]

I wonder why these inputs need to be under the source tree vs any other inputs which are usually supplied via paths pointing to any location on the machine.

One reason for that is developer UX, I believe. When you run prep-source-build.sh, it downloads the artifacts tarball and places it at prereqs/packages/archive. This acts as a well-known location (maybe that's the reasoning for having it predefined in the repo?). So then when you run build.sh, there's no need to pass additional options for the artifacts tarball path which would be annoying for the dev. That's not to say that a well-known location couldn't be defined elsewhere.