/etc/ecs/ecs-init

gistfile1.sh

#!/bin/sh
#
# Copyright 2014 Amazon.com, Inc. or its affiliates. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the
# "License"). You may not use this file except in compliance
# with the License. A copy of the License is located at
#
#     http://aws.amazon.com/apache2.0/
#
# or in the "license" file accompanying this file. This file is
# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
# CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and
# limitations under the License.
#
# description: Starts an Amazon EC2 Container Service Agent container
# config: /etc/ecs/ecs.config


ecs_config="/etc/ecs/ecs.config"
docker="/usr/bin/docker"
agent_tarball="/var/cache/ecs/ecs-agent.tar"
agent_remote_tarball="https://s3.amazonaws.com/amazon-ecs-agent/ecs-agent-latest.tar"
agent_remote_tarball_md5="https://s3.amazonaws.com/amazon-ecs-agent/ecs-agent-latest.tar.md5"
image_name="amazon/amazon-ecs-agent"
logdir="/var/log/ecs"
initlogfile="${logdir}/ecs-init.log"
agentlogfile="ecs-agent.log"

printt() {
	[ -d ${logdir} ] || mkdir -p ${logdir}
	echo "ecs-init [$(date)]: $1" | tee -a "${initlogfile}"
}

throw_error() {
	printt "ERROR $1"
	exit 1
}

download_tarball() {
	printt "Downloading Amazon EC2 Container Service Agent from ${agent_remote_tarball}"
	tmp_tarball="$(mktemp)"
	tmp_md5="$(mktemp)"
	curl "${agent_remote_tarball}" -o "${tmp_tarball}"
	curl "${agent_remote_tarball_md5}" -o "${tmp_md5}"
	download_md5="$(md5sum ${tmp_tarball} | sed 's/ .*//')"
	expected_md5="$(cat ${tmp_md5})"
	if [ ! "${download_md5}" = "${expected_md5}" ]; then
		rm ${tmp_tarball}
		rm ${tmp_md5}
		throw_error "Downloaded tarball with md5sum ${download_md5} did not match ${expected_md5}"
	fi
	mv ${tmp_tarball} ${agent_tarball}
	rm ${tmp_md5}
	return "$?"
}

check_latest() {
	agent_md5="$(md5sum ${agent_tarball} | sed 's/ .*//')"
	curl -I "${agent_remote_tarball}" -H "If-None-Match:${agent_md5}" | grep '304 Not Modified'
	return "$?"
}

pre_start() {
	printt "pre-start"
	[ -x ${docker} ] || return 3

	if [ -z "$(docker images -q ${image_name})" ]; then
		[ -e $agent_tarball ] || download_tarball
		printt "Loading Amazon EC2 Container Service Agent from file ${agent_tarball}"
		docker load <${agent_tarball}
		[ "$?" -eq "0" ] || throw_error "Cannot load Amazon EC2 Container Service Agent ${agent_tarball} into docker"
	fi
}

start() {
	printt "start"
	[ -e ${ecs_config} ] || touch ${ecs_config}
	[ -d ${logdir} ] || mkdir -p ${logdir}
	[ -r ${ecs_config} ] || return 2
	[ -x ${docker} ] || return 3

	printt "Starting Amazon EC2 Container Service Agent"
	docker rm ecs-agent &>/dev/null
	docker run \
		--name ecs-agent \
		-v /var/run/docker.sock:/var/run/docker.sock \
		-v ${logdir}:/log \
		-p 127.0.0.1:51678:51678 \
		--env-file ${ecs_config} \
		-e ECS_LOGFILE=/log/${agentlogfile} \
		${image_name}:latest

	printt "Exited $?"
}

pre_stop() {
	printt "pre-stop"
	[ -x ${docker} ] || return 3

	printt "Stopping Amazon EC2 Container Service Agent"
	docker stop ecs-agent
}

update_cache() {
	printt "update-cache"
	if [ ! -r ${agent_tarball} ]; then
		printt "Could not find cached Amazon EC2 Container Service Agent"
		download_tarball
		return "$?"
	fi
	check_latest
	if [ "$?" -ne "0" ]; then
		printt "Cached Amazon EC2 Container Service Agent does not match latest at ${agent_remote_tarball}"
		download_tarball
	fi
	return "$?"
}

case "$1" in
	pre-start)
		pre_start
		;;
	start)
		start
		;;
	pre-stop)
		pre_stop
		;;
	update-cache)
		update_cache
		;;
	*)
		echo "Usage: $0 {pre-start|start|pre-stop|update-cache}"
		exit 1
esac

exit $?