#!/usr/bin/env python

#

# Copyright (C) 2016 g10 Code GmbH

# Copyright (C) 2004,2008 Igor Belyi <belyi@users.sourceforge.net>

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful, but

# WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

# General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, see <https://www.gnu.org/licenses/>.

# Sample of unattended signing/verifying of a message.

# It uses keys for joe+gpg@example.org generated by genkey.py script

from __future__ import absolute_import, print_function, unicode_literals

import sys

import gpg

from gpg.constants.sig import mode

del absolute_import, print_function, unicode_literals

user = "joe+gpg"

with gpg.Context(pinentry_mode=gpg.constants.PINENTRY_MODE_LOOPBACK) as c:

    keys = list(c.keylist(user))

    if len(keys) == 0:

        sys.exit("No key matching {}.".format(user))

    c.signers = keys[:1]

    c.set_passphrase_cb(lambda *args: "Crypt0R0cks")

    signed_data, _ = c.sign(b"Test message", mode=mode.CLEAR)

    data, result = c.verify(signed_data, verify=keys[:1])

    print("Data: {!r}\nSignature: {!s}".format(data, result.signatures[0]))