#!/bin/sh
# Version: 1.1.2
# Date: 2020-06-24
#
# Resource script for running docker-compose
#
# Description:  Manages docker services using docker-compose as an OCF
#               resource in an High Availability setup.
#               It relies on a well-tested docker compose YAML file which
#               distributed on an identical location on all cluster nodes.
#
# Caveat: 1. A YAML file (docker-compose.yml) and an optional Dockerfile
#            must be provided in a working directory.
#         2. It is suggested to test run the docker-compose and verify
#            on all cluster nodes before enabling this agent.
#
# docker-compose OCF script's Author: Kenny Chen <netman@study-area.org>
# License: GNU General Public License (GPL)
#
#	usage: $0 {start|stop|status|monitor|validate-all|meta-data}
#
#	The "start" arg starts docker service.
#	The "stop" arg stops it.
#
# OCF parameters:
# OCF_RESKEY_binpath
# OCF_RESKEY_dirpath
# OCF_RESKEY_ymlfile
#
##########################################################################
# Initialization:

: ${OCF_ROOT:=/usr/lib/ocf}
: ${OCF_FUNCTIONS_DIR=${OCF_ROOT}/lib/heartbeat}
. ${OCF_FUNCTIONS_DIR}/ocf-shellfuncs

# Defaults
OCF_RESKEY_binpath_default=/usr/bin/docker-compose
OCF_RESKEY_ymlfile_default=docker-compose.yml
: ${OCF_RESKEY_binpath=${OCF_RESKEY_binpath_default}}
: ${OCF_RESKEY_ymlfile=${OCF_RESKEY_ymlfile_default}}

USAGE="Usage: $0 {start|stop|status|monitor|validate-all|meta-data}"

##########################################################################

usage()
{
	echo $USAGE >&2
}

meta_data()
{
cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="docker-compose" version="1.0.3">
<version>1.0</version>
<longdesc lang="en">
Manages docker services using docker-compose as an OCF resource in an High Availability setup.
It relies on a well-tested docker compose YAML file which distributed on an identical location on all cluster nodes.

Caveat: 1. A YAML file (docker-compose.yml) and an optional Dockerfile
           must be provided in a working directory.
        2. It is suggested to test run the docker-compose and verify on all cluster nodes
           before enabling this agent.
</longdesc>
<shortdesc lang="en">This script manages docker services using docker-compose.</shortdesc> 

<parameters>

<parameter name="binpath">
<longdesc lang="en">
The docker-composer binary path.
For example, "/usr/bin/docker-compose"
</longdesc>
<shortdesc lang="en">The docker-composer binary path</shortdesc>
<content type="string" default="$OCF_RESKEY_binpath_default"/>
</parameter>

<parameter name="dirpath" required="1">
<longdesc lang="en">
The directory contains docker compose yaml file.
For example, "/data/docker"
</longdesc>
<shortdesc lang="en">Directory contains docker compose files</shortdesc>
<content type="string"/>
</parameter>

<parameter name="ymlfile">
<longdesc lang="en">
The docker-compose yaml file.
For example, "docker-compose.yml"
</longdesc>
<shortdesc lang="en">The docker compose yaml</shortdesc>
<content type="string" default="$OCF_RESKEY_ymlfile_default"/>
</parameter>

</parameters>

<actions>
<action name="start" timeout="240s"/>
<action name="stop" timeout="20s"/>
<action name="monitor" depth="0" timeout="10s" interval="60s" />
<action name="validate-all" timeout="5s" />
<action name="meta-data"  timeout="5s"/>
</actions>
</resource-agent>
END
exit $OCF_SUCCESS
}

if [ -r "$OCF_RESKEY_binpath" -a -x "$OCF_RESKEY_binpath" ]; then
	COMMAND="$OCF_RESKEY_binpath"
else
	COMMAND="$OCF_RESKEY_binpath_default"
fi

DIR="$OCF_RESKEY_dirpath"
PRE="$(echo ${DIR##*/} | tr A-Z a-z | sed 's/[^a-z0-9]//g')"
YML="$OCF_RESKEY_ymlfile"

docker_kill()
{
	for i in $(docker ps --all | awk -e '$NF ~ /\<'"${PRE}"'_.*_[0-9]+\>/ {print $1}'); do
		docker kill $i >/dev/null 2>&1
		docker rm $i >/dev/null 2>&1 || RTV=false
	done
	if [ "$RTV" = false ]; then
		ocf_log err "failed to kill docker"
		return $OCF_ERR_GENERIC
	else
		RUN=false
	fi
}

docker_compose_status()
{
	# use docker-compose ps if YML found, otherwise try docker ps and kill containers
	if [ -r "$DIR/$YML" ]; then
		DKPS=$(cd $DIR; $COMMAND -f $YML ps -q)

		# get number of all containers
		[ -n "$DKPS" ] && PSNU=$(echo "$DKPS" | wc -l)
		# get number of running containers
		for UUID in $DKPS; do
			UP=$(docker inspect --format='{{.State.Running}}' "$UUID")
			[ "$UP" = "true" ] && UPNU=$((UPNU+1))
		done
		
		if [ "${PSNU:-0}" -ne 0 ]; then
			if [ ${UPNU:-0} -eq 0 ]; then
				ocf_log info "docker service is running but not in up state."
				return $OCF_NOT_RUNNING
			elif [ "$PSNU" -eq $UPNU ]; then
				ocf_log info "docker service is up and running"
				return $OCF_SUCCESS
			else
				ocf_log err "docker service is running with partial up state"
				return $OCF_ERR_GENERIC
			fi
		else
			RUN=false
		fi
	else
		STAT_MSG=$(docker ps --all | awk -e '$NF ~ /\<'"$PRE"'_.*_[0-9]+\>/ {print $1}')
		if [ -z "$STAT_MSG" ]; then
			RUN=false
		else
			ocf_log log "docker service is running without docker-compose, try to kill..."
			docker_kill
		fi
	fi
	[ "$RUN" = false ] && {
		ocf_log info "docker service is not running"
		return $OCF_NOT_RUNNING
	}
}

docker_compose_start()
{
	docker_compose_validate_all
	docker_compose_status >/dev/null 2>&1
	retVal=$?
	# return success if docker service is running
	[ $retVal -eq $OCF_SUCCESS ] && exit $OCF_SUCCESS

	cd $DIR
	$COMMAND -f $YML up -d || {
		ocf_log err "Error. docker-compose returned error $?."
		exit $OCF_ERR_GENERIC
	}

	ocf_log info "docker service started."
	exit $OCF_SUCCESS
}

docker_compose_stop()
{
	# use docker-compose down if YML found, otherwise try docker kill and rm
	if [ -r "$DIR/$YML" ]; then
		docker_compose_validate_all
		cd $DIR
		$COMMAND -f $YML down || {
			ocf_log err "Error on shutting down docker service, try docker kill..."
			RUN_KILL=true
		}
	else
		RUN_KILL=true
	fi
	if [ "$RUN_KILL" = true ]; then
		docker_kill
		[ "$RTV" = false ] && {
			ocf_log err "Error. Could not stop docker services."
			return $OCF_ERR_GENERIC
		}
	fi
	ocf_log info "docker service stopped."
	exit $OCF_SUCCESS
}

docker_compose_monitor()
{
	docker_compose_status
}

docker_compose_validate_all()
{
	if ! check_binary "$OCF_RESKEY_binpath"; then
		ocf_log err "missing binary $OCF_RESKEY_binpath."
		exit $OCF_ERR_ARGS
	fi
	if [ ! -e "$OCF_RESKEY_dirpath" ]; then
		ocf_log err "diretory $OCF_RESKEY_dirpath is not found."
		exit $OCF_ERR_ARGS
	elif [ ! -d "$OCF_RESKEY_dirpath" ]; then
		ocf_log err "diretory $OCF_RESKEY_dirpath is not a directory."
		exit $OCF_ERR_ARGS
	fi
	if [ ! -e "$OCF_RESKEY_dirpath/$OCF_RESKEY_ymlfile" ]; then
		ocf_log err "yaml file $OCF_RESKEY_dirpath/$OCF_RESKEY_ymlfile is not found."
		exit $OCF_ERR_ARGS
	fi

	return $OCF_SUCCESS
}


#
# Main
#

if [ $# -ne 1 ]; then
	usage
	exit $OCF_ERR_ARGS
fi

case $1 in
	start)	
		docker_compose_start
		;;

	stop)	
		docker_compose_stop
		;;

	status)	
		docker_compose_status
		;;

	monitor)
		docker_compose_monitor
		;;

	validate-all)
		docker_compose_validate_all
		;;

	meta-data)
		meta_data
		;;

	usage)	usage
		exit $OCF_SUCCESS
		;;

	*)	usage
		exit $OCF_ERR_UNIMPLEMENTED
		;;
esac