When writing doc/tips/computing_annexed_files.mdwn, I noticed
that a recompute --reproducible followed by a drop and a re-get did not
actually test if the file could be reproducible computed again.
Turns out that get and drop both operate on staged files. If there is an
unstaged modification in the work tree, that's ignored. Somewhat
surprisingly, other commands like info do operate on staged files. So
behavior is inconsistent, and fairly surprising really, when there are
unstaged modifications to files.
Probably this is rarely noticed because `git-annex add` is used to add a
new version of a file, and then it's staged. Or `git mv` is used to move
a file, rather than `mv` of a file over top of an existing file. So it's
uncommon to have an unstaged annexed file in a worktree.
It might be worth making things more consistent, but that's out of scope
for what I'm working on currently.
Also, I anticipate that supporting unlocked files with recompute will
require it to stage changes anyway.
So, make recompute stage the new version of the file.
I considered having recompute refuse to overwrite an existing staged
file. After all, whatever version was staged before will get lost when
the new version is staged over top of it. But, that's no different than
`git-annex addcomputed` being run with the name of an existing staged
file. Or `git-annex add` being run with a new file content when there is
an existing staged file. Or, for that matter, `git add` being ran with a
new content when there is an existing staged file.
Used by git-annex-compute-singularity to make addcomputed --fast work.
Also, simplified git-annex-compute-singularity; there is no need to hard
link the container into place. singularity does not care about the
extension of the container, so can just pass it the annex object file.
In this case, the compute program is run the same as if addcomputed --fast
were used, so it should succeed, without outputting a computed file.
computeInputsUnavailable is in ComputeState for simplicity, but it is
not serialized with the rest of the ComputeState.
Using GIT keys, like are used when exporting git files to special
remotes. Except here the GIT key refers to a file checked into the git
repo.
Note that, since the compute remote uses catObject to get the content,
a symlink that is checked into git does not get followed. This is important
for security, because following a symlink and adding the content to the
repo as an annex object would allow exfiltrating content from outside
the repository.
Instead, the behavior with a symlink is to run the computation on the
symlink target. This may turn out to be confusing, and it might be worth
addcomputed checking if the file in git is a symlink and erroring out.
Or it could follow symlinks as long as the destination is a file in the
repisitory.
I've lost track of them all, but it includes:
* Using the same key backend as was used in the original computation.
* Fixing bug that prevented updating the source file key in the compute
state
* Handling --reproducible and --unreproducible.
* recompute --original of a file using VURL, when the result is
different, but the key remains the same, makes the object file
be updated with the new content
* Detecting some other ways the program behavior can change, just for
completeness.
* Also adds --backend to addcomputed.
When a computed file has been renamed, a recompute needs to write to the
new filename.
I decided to remove --others because it's not clear what it should do in
the face of renames. Should it update only other files that have not
been renamed? Or update files that use the old key to the new key
anywhere in the tree? Or write the other files to the cwd, ignoring
renames? Since --others is just a way to save on compute time, adding
this complexity at this point seems like a bad idea. May revisit later.
Added temporary TODO-compute file
Proper behavior without --others implemented.
And eliminated most of the code duplication through refactoring.
Also, changed it to not stage recomputed files. This way, git diff will
show files that have differences.
The perform action of this still needs work to do the right thing.
In particular, it currently behaves as if --others was always set.
And, it duplicates a lot of code from addcomputed.
This is limited because the remote config is a field/value map. So order
is not preserved, and when 2 parameters have the same field name, only
the last one will be passed.
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.
