#!/bin/sh
#
# push-changes
# John Simpson <jms1@jms1.net> 2004-08-25
#
# pushes new "data" files to slave tinydns servers using SSH
# expects slaves to have the right forced command attached to this key
#
# Last update: 2020-01-01 jms1
# - Cleaning up for public distribution.
# - Using push-targets file instead of hard-coding the server list here.
# - Discovering SSH private key filename rather than hard-coding it here.
# - Clarified that the license is GPLv2 or GPLv3, but not any unknown future
#   version of the GPL (I'm not willing to trust a license that I haven't
#   seen yet.)
#
###############################################################################
#
# Copyright (C) 2004-2020 John Simpson.
#
# 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 or version 3 of the License.
#
# 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, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
# or visit http://www.gnu.org/licenses/gpl.txt
#
###############################################################################

########################################
# Read the list of nameservers

SERVERS=$( sed 's/#.*$//' push-targets )

if [[ -z "$SERVERS" ]]
then
    echo "ERROR: no remote servers were found in the 'push-targets' file"
    exit 1
fi

########################################
# Identify the SSH key file

keyfiles=( $( ls -1 | grep '^id_' | grep -v '\.pub$' ) )
keycount=${#keyfiles[@]}
if [[ $keycount != 1 ]]
then
    echo "ERROR: $keycount id_* files exist, should be 1"
    exit 1
fi

keyfile=${keyfiles[0]}

########################################
# Do the deed

for server in $SERVERS
do
	echo "/---- Start of messages from $server"

	cat data | env - PATH="/usr/bin:/bin" ssh \
		-o 'ConnectTimeout 15' -i $keyfile $server zzz \
		| sed 's/^/| /'

	echo "\\---- End of messages from $server"
done