Re: Linking multiple Git repositories for version tracking

[Avery Pennarun <apenwarr@gmail.com>]

On Fri, Jan 8, 2010 at 12:03 PM, James Beck <james@jmbeck.com> wrote:
> I'm developing firmware that is composed of multiple projects. Each
> section of the firmware has it's own git repository (each section
> correlates to a physical processor). But the firmware as a whole is
> getting to the point where I have to remember which version of Firmware A
> is compatible with Firmware B. If I add a feature to B that requires some
> tweaks in A, I need to know that both A v3.04 and B v2.7 need to be used
> together.
>
> I'm starting to move into alpha with this code, so I really need to have a
> system that keeps track of compatible firmware versions. The best I can
> come up with is a plain text file (or Excel spreadsheet) that lists the
> overall firmware version, and the Git hash for each individual project.
> That way, if I want to load up a particular firmware version, I can
> checkout each hash for that version. Seems foolproof, but not terribly
> easy, and somewhat annoying.
>
> I know submodules might be used, but it's not super obvious how to make
> their paradigm work nicely here. (You check out a version you want, and
> then list all the submodule git hashes for that version? What happens if
> one hash needs updating? Do you branch it?) It seems more complicated than
> I'd like.

This seems like exactly what submodules were designed to do.

1. create a "superproject" for each physical product

2. use submodules to link to the right firmware versions for that product

3. when you make a new release of that physical product, update the
firmware links.

4. when someone wants to check out a particular version of the
product, they retrieve the product's repo and ask git submodule to
checkout the submodules.

Which part is not working for you?

Have fun,

Avery