kolla-build: normalize mtime in archive creation

The reset_userinfo tar filter used when creating plugins and
additions archives normalized uid/gid but left mtime untouched.

Since archives are created after set_time() has already run, and
the default working directory is a fresh temp dir per invocation,
the embedded directory mtime was always the current time.

Docker computes a content checksum for ADD instructions, so a
different mtime in the tar produced a different checksum on every
run.

Fix by setting tarinfo.mtime = 0 in both reset_userinfo filters and
calling os.utime(arc_path, (0, 0)) on the archive file after
creation, making the archives binary-identical across runs for the
same content.

Change-Id: I205dab2c4a74fb9e3cb15c421d5c025849f5632a
Signed-off-by: Michal Nasiadka <mnasiadka@gmail.com>

0 files changed, 0 insertions, 0 deletions