EMiller EMiller - 3 months ago 20
Git Question

How do I extract the git commit ID used to make a zipped git archive?

I can use git archive to create an archive of files present at a particular commit. This is useful, I find, for sending everything to a collaborator, where there's no need to include the git history.

Now I want to know what was the commit ID at the time the archive was made.

The Git documentation says that when creating an archive like

git archive -o latest.zip HEAD
, the commit ID "In ZIP files it is stored as a file comment.".

How do I extract this commit ID out from a zip file "comment"? I am not aware of unix files having comments.

Answer

It's metadata stored in the zip file. Have you tried unzip -Z latest.zip

UnZip 5.52 of 28 February 2005, by Info-ZIP.  Maintained by C. Spieler.  Send
bug reports using http://www.info-zip.org/zip-bug.html; see README for details.

Usage: unzip [-Z] [-opts[modifiers]] file[.zip] [list] [-x xlist] [-d exdir]
  Default action is to extract files in list, except those in xlist, to exdir;
  file[.zip] may be a wildcard.  -Z => ZipInfo mode ("unzip -Z" for usage).

  -p  extract files to pipe, no messages     -l  list files (short format)
  -f  freshen existing files, create none    -t  test compressed archive data
  -u  update files, create if necessary      -z  display archive comment
  -x  exclude files that follow (in xlist)   -d  extract files into exdir

modifiers:                                   -q  quiet mode (-qq => quieter)
  -n  never overwrite existing files         -a  auto-convert any text files
  -o  overwrite files WITHOUT prompting      -aa treat ALL files as text
  -j  junk paths (do not make directories)   -v  be verbose/print version info
  -C  match filenames case-insensitively     -L  make (some) names lowercase
  -X  restore UID/GID info                   -V  retain VMS version numbers
  -K  keep setuid/setgid/tacky permissions   -M  pipe through "more" pager
Examples (see unzip.txt for more info):
  unzip data1 -x joe   => extract all files except joe from zipfile data1.zip
  unzip -p foo | more  => send contents of foo.zip via pipe into program more
  unzip -fo foo ReadMe => quietly replace existing ReadMe if archive file newer