#!/bin/sh
# Copyright (C) 2013-2014  Codethink Limited
#
# 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; version 2 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.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
# This is a "morph deploy" configure extension to configure a Baserock
# build node, as part of a distributed building cluster. It uses the
# following variables from the environment:
#
#    * DISTBUILD_CONTROLLER: if 'yes', machine is set up as the controller.
#    * DISTBUILD_WORKER: if 'yes', machine is set up as a worker.
#    * TROVE_ID: hostname and Trove prefix of the server to pull source
#          from and push built artifacts to.
#    * TROVE_HOST: FQDN of the same server as in TROVE_ID
#
# The following variable is optional:
#
#    * ARTIFACT_CACHE_SERVER: by default artifacts are pushed to the same
#          Trove that served the source, but you can use a different one.
#
# The following variable is required for worker nodes only:
#
#    * CONTROLLERHOST: hostname or IP address of distbuild controller machine.
#    * WORKER_SSH_KEY: identity used to authenticate with Trove
#
# The following variable is required for the controller node only:
#
#    * WORKERS: hostnames or IP address of worker nodes, comma-separated.

set -e

if [ -n "$DISTBUILD_GENERIC" ]; then
    echo "Not configuring the distbuild node, it will be generic"
    exit 0
fi

# Set default values for these two options if they are unset, so that if the
# user specifies no distbuild config at all the configure extension exits
# without doing anything but does not raise an error.
DISTBUILD_CONTROLLER=${DISTBUILD_CONTROLLER-False}
DISTBUILD_WORKER=${DISTBUILD_WORKER-False}

if [ "$DISTBUILD_CONTROLLER" = False -a "$DISTBUILD_WORKER" = False ]; then
    exit 0
fi

set -u

# Check that all the variables needed are present:

error_vars=false

if [ "x$TROVE_HOST" = "x" ]; then
    echo "ERROR: TROVE_HOST needs to be defined."
    error_vars=true
fi

if [ "x$TROVE_ID" = "x" ]; then
    echo "ERROR: TROVE_ID needs to be defined."
    error_vars=true
fi

if [ "$DISTBUILD_WORKER" = True ]; then
    if ! ssh-keygen -lf "$WORKER_SSH_KEY" > /dev/null 2>&1; then
        echo "ERROR: WORKER_SSH_KEY is not a vaild ssh key."
        error_vars=true
    fi

    if [ "x$CONTROLLERHOST" = "x" ]; then
        echo "ERROR: CONTROLLERHOST needs to be defined."
        error_vars=true
    fi
fi

if [ "$DISTBUILD_CONTROLLER" = True ]; then
    if [ "x$WORKERS" = "x" ]; then
        echo "ERROR: WORKERS needs to be defined."
        error_vars=true
    fi
fi

if "$error_vars"; then
    exit 1
fi


ROOT="$1"

DISTBUILD_DATA="$ROOT/etc/distbuild"
mkdir -p "$DISTBUILD_DATA"

# If it's a worker, install the worker ssh key.
if [ "$DISTBUILD_WORKER" = True ]
then
    install -m 0644 "$WORKER_SSH_KEY" "$DISTBUILD_DATA/worker.key"
fi



# Create the configuration file
python <<'EOF' >"$DISTBUILD_DATA/distbuild.conf"
import os, sys, yaml

distbuild_configuration={
    'TROVE_ID': os.environ['TROVE_ID'],
    'TROVE_HOST': os.environ['TROVE_HOST'],
    'DISTBUILD_WORKER': os.environ['DISTBUILD_WORKER'],
    'DISTBUILD_CONTROLLER': os.environ['DISTBUILD_CONTROLLER'],
    'WORKER_SSH_KEY': '/etc/distbuild/worker.key',
}


optional_keys = ('ARTIFACT_CACHE_SERVER', 'CONTROLLERHOST', 'WORKERS',
                 'TROVE_BACKUP_KEYS')

for key in optional_keys:
    if key in os.environ:
        distbuild_configuration[key] = os.environ[key]

yaml.dump(distbuild_configuration, sys.stdout, default_flow_style=False)
EOF