#!/bin/sh
#
# Description:  Manages a PostgreSQL Server as an OCF High-Availability
#               resource
#
# Authors:      Serge Dubrouski (sergeyfd@gmail.com) -- original RA
#               Florian Haas (florian@linbit.com) -- makeover
#               NIPPON TELEGRAPH AND TELEPHONE CORPORATION -- support pg-rex 9.0
#
# Copyright:    2006-2011 Serge Dubrouski <sergeyfd@gmail.com>
#                         and other Linux-HA contributors
# License:      GNU General Public License (GPL)
#
###############################################################################
# OCF parameters:
#  OCF_RESKEY_pgctl - Path to pg_ctl. Default /usr/bin/pg_ctl
#  OCF_RESKEY_start_opt - Startup options, options passed to postgress with -o
#  OCF_RESKEY_ctl_opt - Additional options for pg_ctl (-w, -W etc...)
#  OCF_RESKEY_psql - Path to psql. Default is /usr/bin/psql
#  OCF_RESKEY_pgdata - PGDATA directory. Default is /var/lib/pgsql/data
#  OCF_RESKEY_pgdba - userID that manages DB. Default is postgres
#  OCF_RESKEY_pghost - Host/IP Address where PostgreSQL is listening
#  OCF_RESKEY_pgport - Port where PostgreSQL is listening
#  OCF_RESKEY_monitor_user - PostgreSQL user that pg-rex RA will user for monitor operations.
#  OCF_RESKEY_monitor_password - Password for monitor user.
#  OCF_RESKEY_monitor_sql - SQL script that will be used for monitor operations.
#  OCF_RESKEY_config - Path to the PostgreSQL configuration file for the instance.
#  OCF_RESKEY_pgdb - database to monitor. Default is template1
#  OCF_RESKEY_logfile - Path to PostgreSQL log file. Default is /dev/null
#  OCF_RESKEY_socketdir - Unix socket directory for PostgeSQL.
#  OCF_RESKEY_tmpdir - Path to a directory where flag files are put.
#  OCF_RESKEY_trigger_file - Path to a trigger file whose presence ends recovery in the standby server.
#  OCF_RESKEY_start_check_interval - Interval where start checking of PostgreSQL is carried out.
#  OCF_RESKEY_start_check_multiple - Increased multiple in the interval where start checking of PostgreSQL is carried out.
#  OCF_RESKEY_start_check_interval_limit - Upper limit of the interval where start checking of PostgreSQL is carried out.
#  OCF_RESKEY_rep_mode - Replication mode(auto/sync/async). default is auto
###############################################################################
# Initialization:

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

#
# Get PostgreSQL Configuration parameter
#
get_pgsql_param() {
    local config_file
    local param_name
    local loglevel=err

    if ocf_is_probe; then
        loglevel=warn
    fi

    param_name=$1
 
    #Check that config file exists 
    if [ -n "$OCF_RESKEY_config" ]; then
        config=$OCF_RESKEY_config
    else
        config=$OCF_RESKEY_pgdata/postgresql.conf
    fi

    if [ ! -f "$config" ]; then
        ocf_log $loglevel "Cannot find configuration file $config"
        return
    fi

    perl_code="if (/^\s*$param_name[\s=]+\s*(.*)$/) {
       \$dir=\$1;
       \$dir =~ s/\s*\#.*//;
       \$dir =~ s/^'(\S*)'/\$1/;
       print \$dir;}"

    perl -ne "$perl_code" < $config
}

# Defaults
OCF_RESKEY_pgctl_default=/usr/bin/pg_ctl
OCF_RESKEY_psql_default=/usr/bin/psql
OCF_RESKEY_pgdata_default=/var/lib/pgsql/data
OCF_RESKEY_pgdba_default=postgres
OCF_RESKEY_pghost_default=""
OCF_RESKEY_pgport_default=5432
OCF_RESKEY_config_default=""
OCF_RESKEY_start_opt_default=""
OCF_RESKEY_pgdb_default=template1
OCF_RESKEY_logfile_default=/dev/null
OCF_RESKEY_monitor_user_default=""
OCF_RESKEY_monitor_password_default=""
OCF_RESKEY_monitor_sql_default="select pg_is_in_recovery();"
OCF_RESKEY_tmpdir_default="/var/lib/pg-rex"
OCF_RESKEY_trigger_file_default="${OCF_RESKEY_tmpdir_default}/PGSQL.${OCF_RESKEY_pgport_default}.trigger"
OCF_RESKEY_start_check_interval_default=1
OCF_RESKEY_start_check_multiple_default=2
OCF_RESKEY_start_check_interval_limit_default=30
OCF_RESKEY_rep_mode_default=auto

: ${OCF_RESKEY_pgctl=${OCF_RESKEY_pgctl_default}}
: ${OCF_RESKEY_psql=${OCF_RESKEY_psql_default}}
: ${OCF_RESKEY_pgdata=${OCF_RESKEY_pgdata_default}}
: ${OCF_RESKEY_pgdba=${OCF_RESKEY_pgdba_default}}
: ${OCF_RESKEY_pghost=${OCF_RESKEY_pghost_default}}
: ${OCF_RESKEY_pgport=${OCF_RESKEY_pgport_default}}
: ${OCF_RESKEY_config=${OCF_RESKEY_config_default}}
: ${OCF_RESKEY_start_opt=${OCF_RESKEY_start_opt_default}}
: ${OCF_RESKEY_pgdb=${OCF_RESKEY_pgdb_default}}
: ${OCF_RESKEY_logfile=${OCF_RESKEY_logfile_default}}
: ${OCF_RESKEY_monitor_user=${OCF_RESKEY_monitor_user_default}}
: ${OCF_RESKEY_monitor_password=${OCF_RESKEY_monitor_password_default}}
: ${OCF_RESKEY_monitor_sql=${OCF_RESKEY_monitor_sql_default}}
: ${OCF_RESKEY_tmpdir=${OCF_RESKEY_tmpdir_default}}
: ${OCF_RESKEY_trigger_file=${OCF_RESKEY_trigger_file_default}}
: ${OCF_RESKEY_start_check_interval=${OCF_RESKEY_start_check_interval_default}}
: ${OCF_RESKEY_start_check_multiple=${OCF_RESKEY_start_check_multiple_default}}
: ${OCF_RESKEY_start_check_interval_limit=${OCF_RESKEY_start_check_interval_limit_default}}
: ${OCF_RESKEY_rep_mode=${OCF_RESKEY_rep_mode_default}}

usage() {
    cat <<EOF
	usage: $0 start|stop|status|monitor|promote|demote|notify|meta-data|validate-all|methods

	$0 manages a PostgreSQL Server as an HA resource.

        The 'start' operation starts the PostgreSQL server.
        The 'stop' operation stops the PostgreSQL server.
        The 'status' operation reports whether the PostgreSQL is up.
        The 'monitor' operation reports whether the PostgreSQL is running.
        The 'promote' operation promotes the PostgreSQL server.
        The 'demote' operation demotes the PostgreSQL server.
        The 'notify' operation always returns SUCCESS.
        The 'validate-all' operation reports whether the parameters are valid.
        The 'methods' operation reports on the methods $0 supports.
EOF
  return $OCF_ERR_ARGS
}

#
# meta-data operation
#

pg_rex_meta_data() {
	cat <<EOF
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="pg-rex">
<version>1.0</version>

<longdesc lang="en">
Resource script for PostgreSQL. It manages a PostgreSQL as an HA resource.
</longdesc>
<shortdesc lang="en">Manages a PostgreSQL database instance</shortdesc>

<parameters>
<parameter name="pgctl" unique="0" required="0">
<longdesc lang="en">
Path to pg_ctl command.
</longdesc>
<shortdesc lang="en">pgctl</shortdesc>
<content type="string" default="${OCF_RESKEY_pgctl_default}" />
</parameter>

<parameter name="start_opt" unique="0" required="0">
<longdesc lang="en">
Start options (-o start_opt in pg_ctl). "-i -p 5432" for example.
</longdesc>
<shortdesc lang="en">start_opt</shortdesc>
<content type="string" default="${OCF_RESKEY_start_opt_default}" />

</parameter>
<parameter name="ctl_opt" unique="0" required="0">
<longdesc lang="en">
Additional pg_ctl options (-w, -W etc..).
</longdesc>
<shortdesc lang="en">ctl_opt</shortdesc>
<content type="string" default="${OCF_RESKEY_ctl_opt_default}" />
</parameter>

<parameter name="psql" unique="0" required="0">
<longdesc lang="en">
Path to psql command.
</longdesc>
<shortdesc lang="en">psql</shortdesc>
<content type="string" default="${OCF_RESKEY_psql_default}" />
</parameter>

<parameter name="pgdata" unique="0" required="0">
<longdesc lang="en">
Path to PostgreSQL data directory.
</longdesc>
<shortdesc lang="en">pgdata</shortdesc>
<content type="string" default="${OCF_RESKEY_pgdata_default}" />
</parameter>

<parameter name="pgdba" unique="0" required="0">
<longdesc lang="en">
User that owns PostgreSQL.
</longdesc>
<shortdesc lang="en">pgdba</shortdesc>
<content type="string" default="${OCF_RESKEY_pgdba_default}" />
</parameter>

<parameter name="pghost" unique="0" required="0">
<longdesc lang="en">
Hostname/IP address where PostgreSQL is listening
</longdesc>
<shortdesc lang="en">pghost</shortdesc>
<content type="string" default="${OCF_RESKEY_pghost_default}" />
</parameter>

<parameter name="pgport" unique="0" required="0">
<longdesc lang="en">
Port where PostgreSQL is listening
</longdesc>
<shortdesc lang="en">pgport</shortdesc>
<content type="integer" default="${OCF_RESKEY_pgport_default}" />
</parameter>

<parameter name="monitor_user" unique="0" required="0">
<longdesc lang="en">
PostgreSQL user that pg-rex RA will user for monitor operations. If it's not set
pgdba user will be used.
</longdesc>
<shortdesc lang="en">monitor_user</shortdesc>
<content type="string" default="${OCF_RESKEY_monitor_user_default}" />
</parameter>

<parameter name="monitor_password" unique="0" required="0">
<longdesc lang="en">
Password for monitor user.
</longdesc>
<shortdesc lang="en">monitor_password</shortdesc>
<content type="string" default="${OCF_RESKEY_monitor_password_default}" />
</parameter>

<parameter name="monitor_sql" unique="0" required="0">
<longdesc lang="en">
SQL script that will be used for monitor operations.
</longdesc>
<shortdesc lang="en">monitor_sql</shortdesc>
<content type="string" default="${OCF_RESKEY_monitor_sql_default}" />
</parameter>

<parameter name="config" unique="0" required="0">
<longdesc lang="en">
Path to the PostgreSQL configuration file for the instance
</longdesc>
<shortdesc lang="en">Configuration file</shortdesc>
<content type="integer" default="${OCF_RESKEY_config_default}" />
</parameter>

<parameter name="pgdb" unique="0" required="0">
<longdesc lang="en">
Database that will be used for monitoring.
</longdesc>
<shortdesc lang="en">pgdb</shortdesc>
<content type="string" default="${OCF_RESKEY_pgdb_default}" />
</parameter>

<parameter name="logfile" unique="0" required="0">
<longdesc lang="en">
Path to PostgreSQL server log output file.
</longdesc>
<shortdesc lang="en">logfile</shortdesc>
<content type="string" default="${OCF_RESKEY_logfile_default}" />
</parameter>

<parameter name="socketdir" unique="0" required="0">
<longdesc lang="en">
Unix socket directory for PostgeSQL
</longdesc>
<shortdesc lang="en">socketdir</shortdesc>
<content type="string" default="" />
</parameter>

<parameter name="tmpdir" unique="0" required="0">
<longdesc lang="en">
Path to a directory where flag files are put.
</longdesc>
<shortdesc lang="en">tmpdir</shortdesc>
<content type="string" default="${OCF_RESKEY_tmpdir_default}" />
</parameter>

<parameter name="trigger_file" unique="0" required="0">
<longdesc lang="en">
Trigger file whose presence ends recovery in the standby.
You must set the same value as trigger_file set with recovery.conf of PostgreSQL.
</longdesc>
<shortdesc lang="en">trigger file</shortdesc>
<content type="string" default="${OCF_RESKEY_trigger_file_default}" />
</parameter>

<parameter name="start_check_interval" unique="0" required="0">
<longdesc lang="en">
Interval where start checking of PostgreSQL is carried out.
</longdesc>
<shortdesc lang="en">start check interval</shortdesc>
<content type="integer" default="1" />
</parameter>

<parameter name="start_check_multiple" unique="0" required="0">
<longdesc lang="en">
Increased multiple in the interval where start checking of PostgreSQL is carried out.
</longdesc>
<shortdesc lang="en">start_check_multiple</shortdesc>
<content type="integer" default="2" />
</parameter>

<parameter name="start_check_interval_limit" unique="0" required="0">
<longdesc lang="en">
Upper limit of the interval where start checking of PostgreSQL is carried out.
</longdesc>
<shortdesc lang="en">start check interval limit</shortdesc>
<content type="integer" default="30" />
</parameter>

<parameter name="rep_mode" unique="0" required="0">
<longdesc lang="en">
Replication mode(auto/sync/async).
</longdesc>
<shortdesc lang="en">rep_mode</shortdesc>
<content type="string" default="${OCF_RESKEY_rep_mode_default}" />
</parameter>

</parameters>

<actions>
<action name="start" timeout="3600" />
<action name="stop" timeout="60" />
<action name="status" timeout="60" />
<action name="monitor" depth="0" timeout="60" interval="10"/>
<action name="monitor" depth="0" timeout="60" interval="9" role="Master"/>
<action name="promote" timeout="3600" />
<action name="demote" timeout="60" />
<action name="meta-data" timeout="5" />
<action name="validate-all" timeout="5" />
<action name="methods" timeout="5" />
</actions>
</resource-agent>
EOF
}


#
#	Run the given command in the Resource owner environment...
#
runasowner() {
    local quietrun=""
    local loglevel="-err"
    local var

    for var in 1 2
    do
        case "$1" in
            "-q")
                quietrun="-q"
                shift 1;;
            "warn"|"err")
                loglevel="-$1"
                shift 1;;
            *)
                ;;
        esac
    done

    ocf_run $quietrun $loglevel su $OCF_RESKEY_pgdba -c "cd $OCF_RESKEY_pgdata; $*"
}

#
#       Shell escape
#
escape_string() {
    echo "$*" | sed -e "s/'/'\\\\''/g"
}


#
# What methods/operations do we support?
#

pg_rex_methods() {
  cat <<EOF
	start
	stop
	status
	monitor
	promote
	demote
	notify
	methods
	meta-data
	validate-all
EOF
}


#
# Starts PostgreSQL
#

pgsql_start() {
    local pgctl_options
    local postgres_options

    # Remove postmaster.pid if it exists
    rm -f $PIDFILE

    # Check if we need to create a log file
    if ! check_log_file $OCF_RESKEY_logfile; then
        ocf_log err "PostgreSQL can't write to the log file: $OCF_RESKEY_logfile"
        return $OCF_ERR_GENERIC
    fi

    # Check socket directory
    if [ -n "$OCF_RESKEY_socketdir" ]; then
        check_socket_dir
    fi

    # Set options passed to pg_ctl
    pgctl_options="$OCF_RESKEY_ctl_opt -D $OCF_RESKEY_pgdata -l $OCF_RESKEY_logfile"

    # Set options passed to the PostgreSQL server process
    postgres_options=""
    if [ -n "$OCF_RESKEY_config" ]; then
        postgres_options="$postgres_options -c config_file=${OCF_RESKEY_config}"
    fi
    if [ -n "$OCF_RESKEY_pghost" ]; then
        postgres_options="$postgres_options -h $OCF_RESKEY_pghost"
    fi
    if [ -n "$OCF_RESKEY_start_opt" ]; then
        postgres_options="$postgres_options $OCF_RESKEY_start_opt"
    fi

    # Tack pass-through options onto pg_ctl options
    if [ -n "$postgres_options" ]; then
        pgctl_options="$pgctl_options -o '$postgres_options'"
    fi

    # Invoke pg_ctl
    runasowner "$OCF_RESKEY_pgctl $pgctl_options start"

    if [ $? -eq 0 ]; then
        # Probably started.....
        ocf_log info "PostgreSQL start command sent."
    else
        ocf_log err "Can't start PostgreSQL."
        return $OCF_ERR_GENERIC
    fi

    interval=$OCF_RESKEY_start_check_interval
    while :
    do
        pgsql_monitor warn
        rc=$?
        if [ $rc -eq $OCF_RUNNING_MASTER -o $rc -eq $OCF_SUCCESS ]; then
            break;
        fi

        ocf_log debug "Sleep for $interval second(s)."
        sleep $interval

        interval=`expr $interval \* $OCF_RESKEY_start_check_multiple`
        if [ $interval -gt $OCF_RESKEY_start_check_interval_limit ]; then
            interval=$OCF_RESKEY_start_check_interval_limit
        fi

        ocf_log debug "PostgreSQL still hasn't started yet. Waiting..."
    done
    if [ $rc -eq $OCF_RUNNING_MASTER ]; then
        ocf_log info "PostgreSQL is started as a primary."
    else
        ocf_log info "PostgreSQL is started as a hot standby."
    fi

    return $rc
}

#
# start operation
#

pg_rex_start() {
    if ! rm -f $REPRESS_MONITOR; then
        ocf_log err "Can't remove $REPRESS_MONITOR."
        return $OCF_ERR_GENERIC
    fi

    if ! rm -f $OCF_RESKEY_trigger_file; then
        ocf_log err "Can't remove $OCF_RESKEY_trigger_file."
        return $OCF_ERR_GENERIC
    fi

    if [ -f $REPRESS_START ]; then
        ocf_log err "Starting of PostgreSQL is being repressing."
        return $OCF_ERR_GENERIC
    fi

    if pgsql_status; then
        ocf_log info "PostgreSQL is already running. PID=`cat $PIDFILE`"
        pgsql_monitor
        return $?
    fi

    if [ ! -f $RECOVERY_CONF ]; then
        ocf_log info "recovery.conf doesn't exist, so this resource starts PostgreSQL as a primary."

        ocf_log debug "OCF_RESKEY_CRM_meta_notify_master_uname: '$OCF_RESKEY_CRM_meta_notify_master_uname'"
        if [ x != x$OCF_RESKEY_CRM_meta_notify_master_uname ]; then
            ocf_log err "Master exists already. HOST=$OCF_RESKEY_CRM_meta_notify_master_uname"
            return $OCF_ERR_GENERIC
        fi

        if ! touch $REPRESS_MONITOR; then
            ocf_log err "Can't create $REPRESS_MONITOR."
            return $OCF_ERR_GENERIC
        fi
        ocf_log info "Monitor operation was repressed."

        $CRM_MASTER -v $PROMOTE_ME
    else
        ocf_log info "recovery.conf exists, so this resource starts PostgreSQL as a hot standby."

        ocf_log debug "OCF_RESKEY_CRM_meta_notify_master_uname: '$OCF_RESKEY_CRM_meta_notify_master_uname'"
        if [ x = x$OCF_RESKEY_CRM_meta_notify_master_uname ]; then
            ocf_log err "Master doesn't exit."
            return $OCF_ERR_GENERIC
        fi

        if ! touch $REPRESS_START; then
            ocf_log err "Can't create $REPRESS_START."
            return $OCF_ERR_GENERIC
        fi
        ocf_log info "Start of PostgreSQL was prohibited."

        pgsql_start
        if [ $? -ne $OCF_SUCCESS ]; then
            ocf_log err "PostgreSQL has not started by a hot standby."
            return $OCF_ERR_GENERIC
        fi

        $CRM_MASTER -v $CAN_PROMOTE
    fi

    return $OCF_SUCCESS
}

#
# PostgreSQL is promoted to a primary
# 
pgsql_promote() {
    if [ $1 != async ]; then
        runasowner "$OCF_RESKEY_pgctl -D $OCF_RESKEY_pgdata promote"

        if [ $? -eq 0 ]; then
            # Probably promoted.....
            ocf_log info "PostgreSQL promote command sent."
        else
            ocf_log err "Can't promote PostgreSQL."
            return $OCF_ERR_GENERIC
        fi
    else
        if ! touch $OCF_RESKEY_trigger_file; then
            ocf_log err "Can't create $OCF_RESKEY_trigger_file."
            return $OCF_ERR_GENERIC
        fi
        ocf_log info "Trigger file is created and PostgreSQL is promoted in a primary."
    fi

    while :
    do
        pgsql_monitor warn
        rc=$?
        if [ $rc -eq $OCF_RUNNING_MASTER ]; then
            break;
        fi
        sleep 1
        ocf_log debug "PostgreSQL still hasn't promoted yet. Waiting..."
    done
    ocf_log info "PostgreSQL is promoted to a primary."

    return $OCF_SUCCESS
}

#
# promote operation
#

pg_rex_promote() {
    if ! pgsql_status; then
        if [ -f $REPRESS_START ]; then
            ocf_log err "Starting of PostgreSQL is being repressing."
            return $OCF_ERR_GENERIC
        fi

        if ! touch $REPRESS_START; then
            ocf_log err "Can't create $REPRESS_START."
            return $OCF_ERR_GENERIC
        fi
        ocf_log info "Start of PostgreSQL was prohibited."

        pgsql_start
        if [ $? -ne $OCF_RUNNING_MASTER ]; then
            ocf_log err "PostgreSQL has not started by a primary."
            return $OCF_ERR_GENERIC
        fi

        if ! rm -f $REPRESS_MONITOR; then
            ocf_log err "Can't remove $REPRESS_MONITOR."
            return $OCF_ERR_GENERIC
        fi
        ocf_log info "Monitor operation was resumed."
    else
        rep_mode=$OCF_RESKEY_rep_mode
        if [ $rep_mode = auto ]; then
            if pg_is_sync_mode; then
                rep_mode=sync
            else
                rep_mode=async
            fi
        fi
        ocf_log debug "Replication mode: $rep_mode"

        if [ $rep_mode = sync ]; then
            if ! has_data_catch_up; then
                ocf_log err "Data doesn't catch up. Therefore PostgreSQL can't be promoted."
                return $OCF_ERR_GENERIC
            fi
        fi

        pgsql_promote $OCF_RESKEY_rep_mode
        if [ $? -ne $OCF_SUCCESS ]; then
            return $OCF_ERR_GENERIC
        fi

        $CRM_MASTER -v $PROMOTE_ME
    fi

    return $OCF_SUCCESS
}

#
# Stop PostgreSQL
#

pgsql_stop() {
    # Stop PostgreSQL, do not wait for clients to disconnect
    runasowner "$OCF_RESKEY_pgctl -D $OCF_RESKEY_pgdata stop -m immediate"

    if [ $? -eq 0 ]; then
        # Probably sopped.....
        ocf_log info "PostgreSQL stop command sent."
    else
        ocf_log err "Can't stop PostgreSQL."
        return $OCF_ERR_GENERIC
    fi

    while :
    do
        pgsql_monitor
        rc=$?
        if [ $rc -eq $OCF_NOT_RUNNING ]; then
            # An unnecessary debug log is prevented.
            break;
        fi
        sleep 1
        ocf_log debug "PostgreSQL still hasn't stopped yet. Waiting..."
    done
    ocf_log info "PostgreSQL is stopped."

    # Remove postmaster.pid if it exists
    rm -f $PIDFILE

    return $OCF_SUCCESS
}

#
# demote operation
#

pg_rex_demote() {
    $CRM_MASTER -v $CAN_NOT_PROMOTE

    if ! pgsql_status
    then
        ocf_log info "PostgreSQL is already stopped."
        return $OCF_SUCCESS
    fi

    pgsql_stop
    rc=$?
    if [ $rc -ne $OCF_SUCCESS ]; then
        return $rc
    fi

    return $OCF_SUCCESS
}

#
# stop operation
#

pg_rex_stop() {
    $CRM_MASTER -v $CAN_NOT_PROMOTE

    if ! pgsql_status
    then
        ocf_log info "PostgreSQL is already stopped."
        return $OCF_SUCCESS
    fi

    pgsql_stop
    rc=$?
    if [ $rc -ne $OCF_SUCCESS ]; then
        return $rc
    fi

    return $OCF_SUCCESS
}

#
# is PostgreSQL up?
#

pgsql_status() {
     if [ -f $PIDFILE ]
     then
         PID=`head -n 1 $PIDFILE`
         runasowner "kill -s 0 $PID >/dev/null 2>&1"
         return $?
     fi

     # No PID file
     false
}

#
# status operation
#

pg_rex_status() {
    if pgsql_status
    then
        ocf_log info "PostgreSQL is up"
        exit $OCF_SUCCESS
    else
        ocf_log info "PostgreSQL is down"
        exit $OCF_NOT_RUNNING
    fi
}

#
# Monitor PostgreSQL
#

pgsql_monitor() {
    local loglevel

    # Set the log level of the error message
    loglevel=${1:-err}

    if ! pgsql_status
    then
        ocf_log debug "PostgreSQL is down"
        return $OCF_NOT_RUNNING
    fi

    output=`runsql $loglevel "$OCF_RESKEY_monitor_sql"`
    rc=$?

    if [ $rc -ne $OCF_SUCCESS ]; then
        return $OCF_ERR_GENERIC
    fi

    ocf_log debug "'$OCF_RESKEY_monitor_sql' output: $output"
    case $output in
        f)  ocf_log debug "PostgreSQL is running as a primary."
            return $OCF_RUNNING_MASTER;;

        t)  ocf_log debug "PostgreSQL is running as a hot standby."
            return $OCF_SUCCESS;;

        *)  ocf_log err "Fatal error in '$OCF_RESKEY_monitor_sql': $output"
            return $OCF_ERR_GENERIC;;
    esac
}

#
# monitor operation
#

pg_rex_monitor() {
    if ! ocf_is_probe; then
        if [ -f $REPRESS_MONITOR ]; then
            ocf_log info "Monitor operation is repressing..."
            return $OCF_SUCCESS
        fi
    fi

    pgsql_monitor
    rc=$?
    if ocf_is_probe; then
        if [ $rc -eq $OCF_RUNNING_MASTER -o $rc -eq $OCF_SUCCESS ]; then
            ocf_log warn "PostgreSQL has started before the resource agent starts. PID=`cat $PIDFILE`"

            if ! rm -f $REPRESS_MONITOR; then
                ocf_log err "Can't remove $REPRESS_MONITOR."
                return $OCF_ERR_GENERIC
            fi

            if ! rm -f $OCF_RESKEY_trigger_file; then
                ocf_log err "Can't remove $OCF_RESKEY_trigger_file."
                return $OCF_ERR_GENERIC
            fi

            if ! touch $REPRESS_START; then
                ocf_log err "Can't create $REPRESS_START."
                return $OCF_ERR_GENERIC
            fi
            ocf_log info "Start of PostgreSQL was prohibited."

            if [ $rc -eq $OCF_RUNNING_MASTER ]; then
                ocf_log info "PostgreSQL is running by a primary, so this resource changes to the master."
                $CRM_MASTER -v $PROMOTE_ME
            else
                ocf_log info "PostgreSQL is running by a hot standby, so this resource changes to the slave."
                $CRM_MASTER -v $CAN_PROMOTE
            fi
        fi
    fi

    return $rc
}

check_binary2() {
    if ! have_binary "$1"; then
        ocf_log err "Setup problem: couldn't find command: $1"
        return 1
    fi
    return 0
}

#
# Validate most critical parameters
#

pg_rex_validate_all() {
    if ! check_binary2 "$OCF_RESKEY_pgctl" || 
       ! check_binary2 "$OCF_RESKEY_psql"; then
        return $OCF_ERR_INSTALLED
    fi

    if [ -n "$OCF_RESKEY_config" -a ! -f "$OCF_RESKEY_config" ]; then
        ocf_log err "the configuration file $OCF_RESKEY_config doesn't exist"
        return $OCF_ERR_INSTALLED
    fi

    if [ -n "$OCF_RESKEY_monitor_user" -a ! -n "$OCF_RESKEY_monitor_password" ]
    then
        ocf_log err "monitor password can't be empty"
        return $OCF_ERR_INSTALLED
    fi

    if [ ! -n "$OCF_RESKEY_monitor_user" -a -n "$OCF_RESKEY_monitor_password" ]
    then
        ocf_log err "monitor_user has to be set if monitor_password is set"
        return $OCF_ERR_INSTALLED
    fi

    if [ ! -d "$OCF_RESKEY_tmpdir" ]; then
        ocf_log err "the temporary directory $OCF_RESKEY_tmpdir doesn't exist"
        return $OCF_ERR_INSTALLED
    fi

    if [ "$OCF_RESKEY_rep_mode" = "async" ]; then
        dir=`dirname $OCF_RESKEY_trigger_file`
        if ! runasowner "test -r $dir -a -w $dir"; then
            ocf_log err "$OCF_RESKEY_pgdba can't create or remove $OCF_RESKEY_trigger_file"
            return $OCF_ERR_INSTALLED
        fi
    fi

    return $OCF_SUCCESS
}


#
# Check if we need to create a log file
#

check_log_file() {
    if [ ! -f "$1" ]
    then
        touch $1 > /dev/null 2>&1
        chown $OCF_RESKEY_pgdba:`getent passwd $OCF_RESKEY_pgdba | cut -d ":" -f 4` $1
    fi

    #Check if $OCF_RESKEY_pgdba can write to the log file
    if ! runasowner "test -w $1"
    then
        return 1
    fi

    return 0
}

#
# Check socket directory
#

check_socket_dir() {
    if [ ! -d "$OCF_RESKEY_socketdir" ]; then
        if ! mkdir "$OCF_RESKEY_socketdir"; then
            ocf_log err "Cannot create directory $OCF_RESKEY_socketdir"
            exit $OCF_ERR_GENERIC
        fi

        if ! chown $OCF_RESKEY_pgdba:`getent passwd \
             $OCF_RESKEY_pgdba | cut -d ":" -f 4` "$OCF_RESKEY_socketdir" 
        then
            ocf_log err "Cannot change ownership for $OCF_RESKEY_socketdir"
            exit $OCF_ERR_GENERIC
        fi

        if ! chmod 2775 "$OCF_RESKEY_socketdir"; then
            ocf_log err "Cannot change permissions for $OCF_RESKEY_socketdir"
            exit $OCF_ERR_GENERIC
        fi
    else
        if ! runasowner "touch $OCF_RESKEY_socketdir/test.$$"; then
            ocf_log err "$OCF_RESKEY_pgdba cannot create files in $OCF_RESKEY_socketdir"
            exit $OCF_ERR_GENERIC
        fi
        rm $OCF_RESKEY_socketdir/test.$$
    fi
}

#
# Has data catch up?
#

has_data_catch_up() {
    output=`runsql err "$DATA_CATCH_UP_SQL"`
    if [ $? -eq $OCF_SUCCESS ]; then
        ocf_log debug "'$DATA_CATCH_UP_SQL' output: $output"
        if [ x$output = xt ]; then
            # Data has catch up
            return 0
        fi
    fi

    # Data doesn't catch up
    return 1
}

#
# is synchronous mode?
#

pg_is_sync_mode() {
    if ! runsql err "SHOW ALL;" | grep ^$REP_MODE_PARAM\| >/dev/null 2>&1; then
        ocf_log debug "$REP_MODE_PARAM parameter isn't defined."
        return 1
    fi

    output=`runsql err "$REP_MODE_SQL"`
    if [ $? -eq $OCF_SUCCESS ]; then
        ocf_log debug "'$REP_MODE_SQL' output: $output"
        case $output in
            recv|fsync|apply)
                # Snchronous mode
                return 0
        esac
    fi

    # Asynchronous mode
    return 1
}

#
# run sql script
#

runsql() {
    local loglevel
    local psql_options

    # Set the log level of the error message
    loglevel=${1:-err}

    if ! pgsql_status
    then
        ocf_log info "PostgreSQL is down"
        return $OCF_NOT_RUNNING
    fi

    if [ -n "$OCF_RESKEY_monitor_user" ]; then
        PGUSER=$OCF_RESKEY_monitor_user; export PGUSER
        PGPASSWORD=$OCF_RESKEY_monitor_password; export PGPASSWORD
        psql_options="-p $OCF_RESKEY_pgport $OCF_RESKEY_pgdb"
    else
        psql_options="-p $OCF_RESKEY_pgport -U $OCF_RESKEY_pgdba $OCF_RESKEY_pgdb"
    fi

    if [ -n "$OCF_RESKEY_pghost" ]; then
        psql_options="$psql_options -h $OCF_RESKEY_pghost"
    else
       if [ -n "$OCF_RESKEY_socketdir" ]; then
           psql_options="$psql_options -h $OCF_RESKEY_socketdir"
       fi
    fi

    sql=`escape_string "$2"`
    output=`su $OCF_RESKEY_pgdba -c "cd $OCF_RESKEY_pgdata; $OCF_RESKEY_psql $psql_options -Atc '$sql'" 2>&1`

    rc=$?
    if [ $rc -ne  0 ]; then
        ocf_log $loglevel "PostgreSQL $OCF_RESKEY_pgdb isn't running"
        if [ $rc -eq 1 ]; then
            ocf_log err "Fatal error (out of memory, file not found, etc.) occurred while executing the psql command."
        elif [ $rc -eq 2 ]; then
            ocf_log $loglevel "Connection error (connection to the server went bad and the session was not interactive) occurred while executing the psql command."
        elif [ $rc -eq 3 ]; then
            ocf_log err "Script error (the variable ON_ERROR_STOP was set) occurred while executing the psql command."
        fi
        return $OCF_ERR_GENERIC
    fi

    echo "$output"

    return $OCF_SUCCESS
}

#
#   'main' starts here...
#


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

ocf_log debug "$1 operation start."

PIDFILE=${OCF_RESKEY_pgdata}/postmaster.pid
BACKUPLABEL=${OCF_RESKEY_pgdata}/backup_label
RECOVERY_CONF=${OCF_RESKEY_pgdata}/recovery.conf
REPRESS_MONITOR=${OCF_RESKEY_tmpdir}/PGSQL.${OCF_RESKEY_pgport}.repress_monitor
REPRESS_START=${OCF_RESKEY_tmpdir}/PGSQL.${OCF_RESKEY_pgport}.repress_start

CRM_MASTER="${HA_SBIN_DIR}/crm_master -l reboot"
CAN_NOT_PROMOTE="-INFINITY"
CAN_PROMOTE="100"
PROMOTE_ME="1000"

REP_MODE_PARAM="replication_mode"
REP_MODE_SQL="select current_setting('$REP_MODE_PARAM');"
DATA_CATCH_UP_SQL="select pg_is_in_sync();"

case "$1" in
    methods)    pg_rex_methods
                exit $?;;

    meta-data)  pg_rex_meta_data
                exit $OCF_SUCCESS;;
esac

# $OCF_RESKEY_pgdata has to be initialized at this momemnt
: ${OCF_RESKEY_socketdir=`get_pgsql_param unix_socket_directory`}

pg_rex_validate_all
rc=$?

[ "$1" == "validate-all" ] && exit $rc

if [ $rc -ne 0 ]
then
    case "$1" in
        stop)    exit $OCF_SUCCESS;;
        monitor) exit $OCF_NOT_RUNNING;;
        status)  exit $OCF_NOT_RUNNING;;
        *)       exit $rc;;
    esac
fi

US=`id -u -n`

if [ $US != root -a $US != $OCF_RESKEY_pgdba ]
then
    ocf_log err "$0 must be run as root or $OCF_RESKEY_pgdba"
    exit $OCF_ERR_GENERIC
fi

# What kind of method was invoked?
case "$1" in
    status)     pg_rex_status
                exit $?;;

    monitor)    pg_rex_monitor
                exit $?;;

    start)      pg_rex_start
                exit $?;;

    promote)    pg_rex_promote
                exit $?;;

    demote)     pg_rex_demote
                exit $?;;

    notify)     exit $OCF_SUCCESS;;

    stop)       pg_rex_stop
                exit $?;;
    *)
                exit $OCF_ERR_UNIMPLEMENTED;;
esac