#!/bin/sh
#
# License:      GNU General Public License (GPL)v2
# Description:  Manages Lustre server on a shared storage
# Written by:   Gabriele Paciucci, Nathaniel Clark
# Release Date: 28 February 2017
# Release Version: 1.0.1
# Copyright (c) 2017, Intel Corporation
#
# This program is free software; you can redistribute it and/or modify
# it under the terms and conditions of the GNU General Public License,
# version 2, as published by the Free Software Foundation.
#
# This program is distributed in the hope 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.
#
#
# usage: ./Lustre {start|stop|status|monitor|validate-all|meta-data}
#
#               OCF parameters are as follows:
#               OCF_RESKEY_target - the device or ZFS volume to mount/umount
#               OCF_RESKEY_mountpoint - the mountpoint to use
#               OCF_RESKEY_mountoptions - any mount options to use
#######################################################################
# Initialization:

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


# Variables used by multiple methods


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

# USAGE

usage() {
    echo "usage: $0 {start|stop|status|monitor|validate-all|meta-data}"
}

# META-DATA

meta_data() {
    cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="Lustre">
<version>1.0.1</version>
<longdesc lang="en">
This script manages Lustre Targets (MGT, MDT, OST).
The script is able to mount/umount Lustre Targets.

The standard monitor operation of depth 0 (also known as probe)
checks if the filesystem is mounted and lustre is healthy
</longdesc>
<shortdesc lang="en">Lustre management</shortdesc>

<parameters>

<parameter name="target" unique="1" required="1">
<longdesc lang="en">
The name of the target created during the Lustre format
(e.g. /dev/sda, ZPOOL/MGS, /dev/mapper/mpatha)
</longdesc>
<shortdesc lang="en">Lustre target name</shortdesc>
<content type="string" default="" />
</parameter>

<parameter name="mountpoint" unique="1" required="1">
<longdesc lang="en">
The mount point where the Lustre target will be mounted.
</longdesc>
<shortdesc lang="en">Mount point for Lustre</shortdesc>
<content type="string" default="" />
</parameter>

<parameter name="mountoptions" unique="1" required="0">
<longdesc lang="en">
Any additional mount options for the Lustre target. (eg: "-o skpath=/path/to/keys")
</longdesc>
<shortdesc lang="en">Mount options for Lustre target</shortdesc>
<content type="string" default="" />
</parameter>

</parameters>

<actions>
<action name="start"   timeout="300s" />
<action name="stop"    timeout="300s" />
<action name="monitor" depth="0"  timeout="300s" interval="20s" />
<action name="validate-all"  timeout="30s" />
<action name="meta-data"  timeout="5s" />
</actions>
</resource-agent>
END
    exit $OCF_SUCCESS
}

#####################################################################
# STATUS
#

lustre_is_mounted () {
    # Verify if this is consistent, check pointpoint and filesystem
    # against source (i.e. device)
    local dev=$(findmnt -t lustre -ln -o SOURCE -T $(realpath "$OCF_RESKEY_mountpoint"))

    [ -n "$dev" ] &&
    [ "$dev" == "$OCF_RESKEY_target" -o "$dev" == $(realpath "$OCF_RESKEY_target") ]
}

lustre_monitor () {
    if ! lustre_is_mounted; then
	ocf_log err "$OCF_RESKEY_target is not mounted"
	return $OCF_NOT_RUNNING
    fi

    # TODO: Add better status monitoring
    return $OCF_SUCCESS
}

#####################################################################
# ACTIONS
#

lustre_mount () {
    if ! lustre_is_mounted; then
	ocf_log info "Starting to mount $OCF_RESKEY_target"

	output=$(mount -t lustre $OCF_RESKEY_mountoptions $OCF_RESKEY_target $OCF_RESKEY_mountpoint 2>&1)
	rc=$?
	if [ $rc -eq 0 ]; then
	    ocf_log info "$OCF_RESKEY_target mounted successfully"
	    [ -n "$output" ] && ocf_log info "$output"
	    return $OCF_SUCCESS
	fi
	ocf_log err "$OCF_RESKEY_target mount failed, rc=$rc"
	ocf_log err "$output"
	return $OCF_ERR_GENERIC
    fi
    return $OCF_SUCCESS
}

lustre_umount () {
    if lustre_is_mounted; then
	ocf_log info "Starting to unmount $OCF_RESKEY_target"

	output=$(umount $OCF_RESKEY_mountpoint 2>&1)
	rc=$?
	if [ $rc -eq 0 ]; then
	    ocf_log info "$OCF_RESKEY_target unmounted successfully"
	    [ -n "$output" ] && ocf_log info "$output"
	    return $OCF_SUCCESS
	fi
	ocf_log err "$OCF_RESKEY_target unmount failed, rc=$rc"
	ocf_log err "$output"
	return $OCF_ERR_GENERIC
    fi
    return $OCF_SUCCESS
}

all_start () {
    lustre_mount
    mnt_success=$?
    if [ "$mnt_success" != "$OCF_SUCCESS" ]; then
	ocf_log err "$OCF_RESKEY_target can not be mounted with this error: $mnt_success"
	return $OCF_ERR_GENERIC
    fi
    return $OCF_SUCCESS
}

all_stop () {
    lustre_umount
    mnt_success=$?
    if [ "$mnt_success" != "$OCF_SUCCESS" ]; then
	ocf_log err "$OCF_RESKEY_target can not be unmounted with this error: $mnt_success"
	return $OCF_ERR_GENERIC
    fi
    return $OCF_SUCCESS
}

validate () {
    if [ ! -d "$(realpath $OCF_RESKEY_mountpoint)" ]; then
	ocf_log err "$OCF_RESKEY_mountpoint can not be found"
	return $OCF_ERR_INSTALLED
    fi
    if ! modinfo -n lustre >/dev/null 2>&1; then
	ocf_log err "lustre module not available"
	return $OCF_ERR_INSTALLED
    fi
    return $OCF_SUCCESS
}

case $1 in
    meta-data)          meta_data;;
    start)              all_start;;
    stop)               all_stop;;
    status|monitor)     lustre_monitor;;
    validate-all)       validate;;
    usage)              usage
	exit $OCF_SUCCESS
	;;
    *)                  exit $OCF_ERR_UNIMPLEMENTED;;
esac