protonkey/protonkey

#!/bin/sh

# Copyright (c) 2022–2023 Emma Tebibyte <emma@tebibyte.media>
# SPDX-License-Identifier: AGPL-3.0-or-later
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the Free
# Software Foundation, either version 3 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 Affero General Public License for more
# details.
#
# You should have received a copy of the GNU Affero General Public License along
# with this program. If not, see https://www.gnu.org/licenses/.


argv0="$0"

if ! command -v curl > /dev/null; then
  printf "%s: Missing dependency: curl(1)\n" "$0" 1>&2
  exit 69 # sysexits(3) EX_UNAVAILABLE
fi

if test -z "$1"; then
  printf "Usage: %s [ProtonMail address...]\n" "$argv0" 1>&2
  exit 64 # syexits(3) EX_USAGE
fi

while test -n "$1"; do
  URL="https://api.protonmail.ch/pks/lookup?op=get&search=$1"
  RESPONSE="$(curl -s "$URL")"

  if [ "$RESPONSE" = 'No key found' ]; then
    printf "%s: %s: %s\n" "$argv0" "$1" "$RESPONSE" 1>&2
    exit 76 # sysexits(3) EX_PROTOCOL
  else
    printf "%s\n" "$RESPONSE"
  fi
shift
done