#!/bin/sh
#
#
#   zabbixserver OCF RA for zabbix_server daemon
#
# Copyright (c) 2012 Krzysztof Gajdemski <songo@debian.org.pl>
#                    All Rights Reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#
# Further, this software is distributed without any warranty that it is
# free of the rightful claim of any third person regarding infringement
# or the like.  Any license provided herein, whether implied or
# otherwise, applies only to this software file.  Patent licenses, if
# any, provided herein do not apply to combinations of this program with
# other software, or any other product whatsoever.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
#

#######################################################################
# Initialization:

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

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

#
# Defaults
#
OCF_RESKEY_binary_default="zabbix_server"
OCF_RESKEY_pid_default="/var/run/zabbix-server/zabbix_server.pid"
OCF_RESKEY_config_default=""

: ${OCF_RESKEY_binary=${OCF_RESKEY_binary_default}}
: ${OCF_RESKEY_pid=${OCF_RESKEY_pid_default}}
: ${OCF_RESKEY_config=${OCF_RESKEY_config_default}}

# sleep interval when waiting for threads cleanup
sleepint=1

#
# Functions
#
zabbixserver_meta_data() {
    cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="zabbixserver" version="0.0.1">
<version>1.0</version>

<longdesc lang="en">
This is a Zabbix server Resource Agent for zabbix_server monitoring
daemon. See: http://www.zabbix.com/
</longdesc>
<shortdesc lang="en">Zabbix server resource agent</shortdesc>

<parameters>

<parameter name="binary" unique="0" required="0">
<longdesc lang="en">
Location of the zabbix_server binary.
</longdesc>
<shortdesc lang="en">Zabbix server binary</shortdesc>
<content type="string" default="${OCF_RESKEY_binary_default}" />
</parameter>

<parameter name="pid" unique="1" required="0">
<longdesc lang="en">
Path to zabbix_server pidfile. As it's created by daemon itself
it must be the same as specified in the Zabbix configuration file
with parameter 'PidFile='.
</longdesc>
<shortdesc lang="en">Path to pidfile</shortdesc>
<content type="string" default="${OCF_RESKEY_pid_default}" />
</parameter>

<parameter name="config" unique="1" required="0">
<longdesc lang="en">
Path to zabbix_server configuration file. Assumed server default
if not specified.
</longdesc>
<shortdesc lang="en">Path to configuration file</shortdesc>
<content type="string" default="${OCF_RESKEY_config_default}" />
</parameter>

</parameters>

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

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


zabbixserver_usage() {
    cat <<END
usage: $0 {start|stop|monitor|validate-all|meta-data}

Expects to have a fully populated OCF RA-compliant environment set.
END
}

#
# Get an actual PID from a given pidfile. If it can't
# be found then return 1
#
getpid() {
    # pidfile doesn't exists
    [ -f $1 ] || return 1
    sed -n '1 { /[0-9]/p }' $1

    return 0
}

#
# Check for the server configuration file
#
check_config() {
    # check only when it is specified by user
    if [ ! -z "$1" ] && [ ! -f "$1" ]; then
        if ocf_is_probe; then
            ocf_log info "Can't read configuration file $1 during probe"
        else
            ocf_exit_reason "Can't read configuration file $1"
            return 1
        fi
    fi

    return 0
}

#
# Start Zabbix daemon
#
startserver() {
    local command
    local params

    command=$OCF_RESKEY_binary

    # use additional parameters if specified
    if [ "$OCF_RESKEY_config" ]; then
        params="--config $OCF_RESKEY_config"
        command="$command $params"
    fi

    ocf_log debug "Starting server using command: $command"

    ocf_run $command
}

#
# Check the process status (PID is given as an argument)
#
process_status() {
    local pid

    pid=$1

    # check if parent process is running
    ocf_run -q kill -s 0 $pid 2> /dev/null 1>&2
}

#
# start the agent
#
zabbixserver_start() {
    local rc

    # check the resource status
    zabbixserver_monitor
    rc=$?
    case "$rc" in
    $OCF_SUCCESS)
        ocf_log info "Resource is already running"
        return $OCF_SUCCESS
        ;;
    $OCF_NOT_RUNNING)
        ;;
    *)
        exit $OCF_ERR_GENERIC
        ;;
    esac

    # remove stale pidfile if it exists
    if [ -f $OCF_RESKEY_pid ]; then
        ocf_log info "Removing stale pidfile"
        rm $OCF_RESKEY_pid
    fi

    startserver
    if [ $? -ne 0 ]; then
        ocf_exit_reason "Can't start Zabbix server"
        return $OCF_ERR_GENERIC
    fi

    # wait if it starts really
    while ! zabbixserver_monitor; do
        ocf_log debug "Resource has not started yet, waiting"
        sleep $sleepint
    done

    return $OCF_SUCCESS
}

#
# stop the agent
#
zabbixserver_stop() {
    local pid
    local rc

    # check the resource status
    zabbixserver_monitor
    rc=$?
    case "$rc" in
    $OCF_SUCCESS)
        ;;
    $OCF_NOT_RUNNING)
        ocf_log info "Resource is already stopped"
        return $OCF_SUCCESS
        ;;
    *)
        exit $OCF_ERR_GENERIC
        ;;
    esac

    pid=`getpid $OCF_RESKEY_pid`
    if [ $? -ne 0 ]; then
        ocf_exit_reason "Can't find process PID"
        return $OCF_ERR_GENERIC
    fi

    # kill the process
    ocf_run -q kill $pid
    if [ $? -ne 0 ]; then
        ocf_exit_reason "Can't stop process (PID $pid)"
        return $OCF_ERR_GENERIC
    fi

    # Wait until the parent process terminates.
    # NOTE: The parent may be still waiting for its children. A regular monitor
    # function will not detect this condition because the pidfile may be
    # removed just now.
    while process_status $pid; do
        ocf_log debug "Waiting for process to terminate..."
        sleep $sleepint
    done

    # wait if it stops really
    while zabbixserver_monitor; do
        ocf_log debug "Resource has not stopped yet, waiting"
        sleep $sleepint
    done

    # remove stale pidfile if it exists
    if [ -f $OCF_RESKEY_pid ]; then
        ocf_log debug "Pidfile still exists, removing"
        rm $OCF_RESKEY_pid
    fi

    return $OCF_SUCCESS
}

#
# resource monitor
#
zabbixserver_monitor() {
    local pid

    pid=`getpid $OCF_RESKEY_pid`
    if [ $? -eq 0 ]; then
        process_status $pid
        if [ $? -eq 0 ]; then
            ocf_log debug "Resource is running"
            return $OCF_SUCCESS
        fi
    fi

    ocf_log info "Resource is not running"
    return $OCF_NOT_RUNNING
}

#
# validate configuration
#
zabbixserver_validate_all() {
    check_config $OCF_RESKEY_config || return $OCF_ERR_INSTALLED
    ocf_mkstatedir root 755 `dirname $OCF_RESKEY_pid` || return $OCF_ERR_INSTALLED
    return $OCF_SUCCESS
}

#
# main
#
OCF_REQUIRED_PARAMS=""
OCF_REQUIRED_BINARIES="$OCF_RESKEY_binary"
ocf_rarun $*