Git ref imports

[tnavatar]

Allows use of git refs for imported schema, rather than relying on Git submodules.

[ahwagner]

This is a useful feature addition towards removing git submodules.

However, this breaks assumptions about the version of the source schema file with respect to imported artifacts from upstream repositories. If a downstream repository uses a different version of metaschema processor, it may result in different reprocessed artifacts, causing potential sync issues.

I request that this is merged into a feature branch (not main) on ga4gh/gks-metaschema until such a time as supplemental features can be added to bring this approach to parity with git submodule.

[tnavatar]

However, this breaks assumptions about the version of the source schema file with respect to imported artifacts from upstream repositories. If a downstream repository uses a different version of metaschema processor, it may result in different reprocessed artifacts, causing potential sync issues.

Could you be a little more specific about how this could come about? A concrete example would help me to understand.

One thing I can see that this would break is if an upstream repository itself has imports included with git submodules. These would effectively be unresolvable. I don't think this can be fixed, I think it simply has to be unsupported to include a library via git refs that has dependencies declared via git submodules.

[tnavatar]

In the meantime, happy to accept your suggestion to merge it into a feature branch in this repo.