Re: [PATCH 0/4] Expose gpgsig in pretty-print

[John Passaro <john.a.passaro@gmail.com>]

On Thu, Dec 13, 2018 at 11:12 PM Michał Górny <mgorny@gentoo.org> wrote:
>
> On Thu, 2018-12-13 at 16:22 -0500, John Passaro wrote:
> > Currently, users who do not have GPG installed have no way to discern
> > signed from unsigned commits without examining raw commit data. I
> > propose two new pretty-print placeholders to expose this information:
> >
> > %GR: full ("R"aw) contents of gpgsig header
> > %G+: Y/N if the commit has nonempty gpgsig header or not
> >
> > The second is of course much more likely to be used, but having exposed
> > the one, exposing the other too adds almost no complexity.
> >
> > I'm open to suggestion on the names of these placeholders.
> >
> > This commit is based on master but e5a329a279 ("run-command: report exec
> > failure" 2018-12-11) is required for the tests to pass.
> >
> > One note is that this change touches areas of the pretty-format
> > documentation that are radically revamped in aw/pretty-trailers: see
> > 42617752d4 ("doc: group pretty-format.txt placeholders descriptions"
> > 2018-12-08). I have another version of this branch based on that branch
> > as well, so you can use that in case conflicts with aw/pretty-trailers
> > arise.
> >
> > See:
> > - https://github.com/jpassaro/git/tree/jp/pretty-expose-gpgsig
> > - https://github.com/jpassaro/git/tree/jp/pretty-expose-gpgsig--based-on-aw-pretty-trailers
> >
> > John Passaro (4):
> >   pretty: expose raw commit signature
> >   t/t7510-signed-commit.sh: test new placeholders
> >   doc, tests: pretty behavior when gpg missing
> >   docs/pretty-formats: add explanation + copy edits
> >
> >  Documentation/pretty-formats.txt |  21 ++++--
> >  pretty.c                         |  36 ++++++++-
> >  t/t7510-signed-commit.sh         | 125 +++++++++++++++++++++++++++++--
> >  3 files changed, 167 insertions(+), 15 deletions(-)
> >
> >
> > base-commit: 5d826e972970a784bd7a7bdf587512510097b8c7
> > prerequisite-patch-id: aedfe228fd293714d9cd0392ac22ff1cba7365db
>
> Just a suggestion: since the raw signature is not very useful without
> the commit data to check it against, and the commit data is non-trivial
> to construct (requires mangling raw data anyway), maybe you could either
> add another placeholder to get the data for signature verification, or
> (alternatively or simultaneously) add a placeholder that prints both
> data and signature in the OpenPGP message format (i.e. something you can
> pass straight to 'gpg --verify').
>

That's a great idea!

Then I might rename the other new placeholders too:

%Gs: signed commit signature (blank when unsigned)
%Gp: signed commit payload (i.e. in practice minus the gpgsig header;
also blank when unsigned as well)
%Gq: query/question whether is signed commit ("Y"/"N")

Thus establishing %G<lowercase> as the gpg-related placeholders that
do not actually require gpg.

And add a test that %Gp%n%Gs or the like passes gpg --verify.

I'll put in a v2 later today or tomorrow. Thank you for the feedback!

--
JP