Re: I lost my commit signature

From: Jeff King <peff@peff.net>
Date: Jun 14, 2016, 07:58 UTC
Message-ID: <20160614075824.GB12563@sigill.intra.peff.net>
In-Reply-To: <CAGrdoOrrpc7OiU74fa-qpjLNxOtm4upAOAfWPG6VbWUjyE0C2Q@mail.gmail.com>

On Tue, Jun 14, 2016 at 03:50:43PM +0800, ZhenTian wrote:

Show 13 quoted lines

> I commit with -S argument, and I got some output like this:
> 
> You need a passphrase to unlock the secret key for
> user: "Tian Zhen <tianzhen@honovation.com>"
> 4096-bit RSA key, ID 2EF2AD6E, created 2016-05-21
> 
> [master d107770] feat: mobile support free freight hint, closed #1417
>  8 files changed, 58 insertions(+), 29 deletions(-)
>  rewrite static/css/mobile.min.css (64%)
>
> but when I check git log with --show-signature, I can't find my sign.
> 
> my git is 2.4.8, and OS is Ubuntu 14.04.4

Here's a reproduction which should work (and does for me):

  $ git init
  $ echo content >file
  $ git add file
  $ git commit -m foo -S
  You need a passphrase to unlock the secret key for
  user: "Jeff King <peff@peff.net>"
  4096-bit RSA key, ID F9430ED9, created 2016-02-03 (main key ID D7B337A8)

  [master (root-commit) 6b0b230] foo
   1 file changed, 1 insertion(+)
   create mode 100644 file

  $ git log --show-signature
  commit 6b0b230c79f8912bf8b21afc0d12d2cbf54cc74d (HEAD -> master)
  gpg: Signature made Tue 14 Jun 2016 03:55:11 AM EDT using RSA key ID F9430ED9
  gpg: Good signature from "Jeff King <peff@peff.net>"
  gpg:                 aka "Jeff King <peff@github.com>"
  Author: Jeff King <peff@peff.net>
  Date:   Tue Jun 14 03:55:11 2016 -0400

foo

Does something similar work for you? If so, then we need to figure out what happened in your original case. Can you show the exact commands you ran, and what they did output?

If the simple case above doesn't work, then we need to figure out whether the commit doesn't get a signature, or whether "log --show-signature" is not working on your system. For the former, I'd try "git cat-file commit HEAD", which should show the encoded signature block. If it's there, then presumably something is not working in calling gpg.

-Peff