On Fri, Jan 29, 2016 at 09:28:44AM -0500, Stefan Monnier wrote: > > The primary goal of fast-import is to write that packfile. It kind of > > sounds like you are using the wrong tool for the job. > > Yes, I realize that. But in some cases it's the best tool available. > `fast-import' is very close to being a "generic access API" which can be > used instead of something like libgit. I think it'd be good to push it > yet a bit closer.
I'm not sure I agree. Git tries to make its innards available via flexible plumbing commands. If we're not succeeding, I think that should be fixed, rather than trying to shoe-horn an unrelated command to do the job, even if it would be less code. > > Can you elaborate on what you are sending to fast-import (preferably > > with a concrete example)? > > I'm sending a stream of "progress <foo>; cat-blob <foo>", basically. > > The concrete example is in [BuGit](https://gitlab.com/monnier/bugit), > see for example > https://gitlab.com/monnier/bugit/commit/3678dcb8830a9c79c6f3404d75d63e6dd07bfe4c You can use custom cat-file formatting to output your "name" strings as part of the same field. IOW, something like: git cat-file -p refs/heads/bugit-master:numbers | awk '{print $3 " " $4 }' | git cat-file --batch="%(rest)" | while read number; do read id; # assuming blob contents are single-line read _junk; # assumes blob ended in its own newline $fun "$id" "$number" done That's from a fairly cursory reading of that bugit patch, though, so I might be missing some requirement. > Yes, I switched to using "cat-file --batch" instead, but it's less > convenient (I can't intersperse ad-hoc info in the output, the way I can > with "progress" in fast-import) and there are cases where the list of > files I need to extract cannot be determined without first looking at > some of those extracted files (I currently have been able to avoid > this in BuGit, luckily). I think the example above should handle the "intersperse" thing. If you're really going to do a lot of interactive back-and-forth access of objects, though, I think you want to set up pipes to cat-file. It's a little tedious to allocate fifos, but something like: mkfifo in out (exec git cat-file --batch <in >out) & exec 8>in exec 9<out echo $sha >&8 read mode type size <&9 read content ;# or read $size, or read until newline echo $content >&8 ;# imagine content is another sha to look up ...read from &9, etc.. The fifos and numbered descriptors are annoying, but that's shell for you. I suspect using "fast-import" wouldn't be much different. One feature I do think would be useful (and almost implemented when I added --batch-check=<format>) is a formatter for the object content, with a pretty modifier. I.e., it would be nice to do: echo $some_tree | git cat-file --batch-check="%(objectsize:pretty) %(contents:pretty)" to work as the rough equivalent of "git cat-file -p" (but here you could feed multiple trees and get multiple answers). -Peff -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
