For these, use VURL and URL keys, with an "annex-compute:" URI prefix.
These URL keys will look something like this:
URL--annex-compute&cbar4,63pconvert,3-f4d3d72cf3f16ac9c3e9a8012bde4462
Generally it's too long so most of it gets md5summed. It's a little
ugly, but it's what fell out of the existing URL key generation
machinery. I did consider special casing to eg
"URL--annex-compute&c4d3d72cf3f16ac9c3e9a8012bde4462". But it seems at
least possibly useful that the name of the file that was computed is
visible and perhaps one or two words of the git-annex compute command
parameters.
Note that two different output files from the same computation will get
the same URL key. And these keys should remain stable.
Working pretty well. Mostly. But:
* Does not yet support inputs that are non-annexed files checked into git
* --fast is currently broken (will need something like VURL keys)
* --unreproducible still uses a checksumming backend, so drop and get
again will likely fail (needs probably to use an URL key or something
like one)
The compute special remote seems to work pretty well too. Eg,
getting from it works, and dropping content that is present in it works.