trans: add transpiler

[arithx]

Still testing against plume & stream-metadata-generator

[arithx]

Also looking for ideas on where this should live

[ashcrow]

Added comments in the draft.

[jlebon]

Hmm, so the idea here is that one would do e.g.:

./trans.py builds/ID/arch1/meta.json builds/ID/arch2/meta.json ...

?

Could we instead just point it at the cosa workdir and pass the ID separately? So e.g. ./trans.py [--workdir /cosa/workdir] --build-id ID. Then it can lookup which architectures are available using the new schema (for now, could probably just assume the basearch of the current machine if it's the old schema -- edit: or keep parsing the ref).

[arithx]

I switched it over to accepting a --workdir & --build-id. It searches for a meta.json in all sub-directories in $workdir/builds/$buildid. I left the actual architecture determination to parsing out coreos-assembler.basearch.

While doing so I also dropped the --output-file argument to instead write the output file into $workdir/builds/$buildid/release.json every time.

[jlebon]

Also looking for ideas on where this should live

Hmm, tempted to just include it in cosa. Would just need to make the builds.coreos.fp.o/... URL a flag. Though it muddles the distinction with the existing meta.json.

Or maybe let's put it in https://github.com/coreos/fedora-coreos-releng-automation/ for now. And e.g. if RHCOS also wants to adopt this in the future, we can "upstream" it into cosa.

[ashcrow]

Also looking for ideas on where this should live

cosa makes the most sense but we should be careful to not allow it to trample on the current meta.json in use in RHCOS. If it is used to produce a file that won't be used by RHCOS but it will be helpful for FCOS I see no issue with it :-).

[arithx]

Putting it in https://github.com/coreos/fedora-coreos-releng-automation/ for now and eventually upstreaming it into cosa makes sense to me. I'll create a PR over there once I get this tested.