garbd

#!/bin/sh
#
#
# GARBD (Galera Arbitrator)
#
# Description:  
#
# Authors:      Sébastien Han
#
# Support:      codership-team@googlegroups.com
# License:      Apache Software License (ASL) 2.0
#
#
# See usage() function below for more details ...
#
# OCF instance parameters:
#   OCF_RESKEY_binary
#   OCF_RESKEY_gcomm_url
#   OCF_RESKEY_donor_port
#   OCF_RESKEY_cluster_name
#   OCF_RESKEY_pid
#   OCF_RESKEY_additional_parameters
#######################################################################
# Initialization:

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

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

# Fill in some defaults if no values are specified

OCF_RESKEY_binary_default="garbd"
OCF_RESKEY_user_default="garbd"
OCF_RESKEY_pid_default="$HA_RSCTMP/$OCF_RESOURCE_INSTANCE.pid"
OCF_RESKEY_donor_port="4567"

: ${OCF_RESKEY_binary=${OCF_RESKEY_binary_default}}
: ${OCF_RESKEY_user=${OCF_RESKEY_user_default}}
: ${OCF_RESKEY_pid=${OCF_RESKEY_pid_default}}
: ${OCF_RESKEY_donor_port=${OCF_RESKEY_donor_port_default}}

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

usage() {
    cat <<UEND
        usage: $0 (start|stop|validate-all|meta-data|status|monitor)

        $0 manages a Galera arbitrator (garbd) process as an HA resource 

        The 'start' operation starts the garbd service.
        The 'stop' operation stops the garbd service.
        The 'validate-all' operation reports whether the parameters are valid
        The 'meta-data' operation reports this RA's meta-data information
        The 'status' operation reports whether the garbd service is running
        The 'monitor' operation reports whether the garbd service seems to be working

UEND
}

meta_data() {
    cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="garbd">
<version>1.0</version>

<longdesc lang="en">
Resource agent for the Galera arbitrator (garbd). http://www.codership.com/wiki/doku.php?id=galera_arbitrator.
</longdesc>
<shortdesc lang="en">Manages the Galera arbitrator Service (garbd)</shortdesc>
<parameters>

<parameter name="binary" unique="0" required="0">
<longdesc lang="en">
Location of the Galera arbitrator binary (garbd)
</longdesc>
<shortdesc lang="en">Galera arbitrator binary (garbd)</shortdesc>
<content type="string" default="${OCF_RESKEY_binary_default}" />
</parameter>

<parameter name="user" unique="0" required="1">
<longdesc lang="en">
User running Galera arbitrator (garbd) service
</longdesc>
<shortdesc lang="en">Galera arbitrator (garbd) user</shortdesc>
<content type="string" default="${OCF_RESKEY_user_default}" />
</parameter>

<parameter name="pid" unique="0" required="0">
<longdesc lang="en">
The pid file to use for this Galera arbitrator (garbd) process
</longdesc>
<shortdesc lang="en">Galera arbitrator (garbd) pid file</shortdesc>
<content type="integer" default="${OCF_RESKEY_pid_default}" />
</parameter>

<parameter name="donor_port" unique="0" required="1">                                                                                                                                                              
<longdesc lang="en">                                                                                                                                                                                                      
The listening port number of the donor node.                                                                                                                                    
</longdesc>                                                                                                                                                                                                               
<shortdesc lang="en">Donor listenning port</shortdesc>                                                                                                                                                                      
<content type="integer" default="${OCF_RESKEY_donor_port_default}" />                                                                                                                                              
</parameter>  

<parameter name="gcomm_url" unique="0" required="1">                                                                                                                                                              
<longdesc lang="en">                                                                                                                                                                                                      
The gcomm url, ip address of a node member of the cluster                                                                                                                                       
</longdesc>                                                                                                                                                                                                               
<shortdesc lang="en">Donor URL</shortdesc>                                                                                                                                                                      
<content type="string" default="${OCF_RESKEY_gcomm_url_default}" />                                                                                                                                              
</parameter>  

<parameter name="cluster_name" unique="0" required="1">                                                                                                                                                              
<longdesc lang="en">                                                                                                                                                                                                      
The name of your galera cluster. SHOW VARIABLES LIKE 'wsrep_cluster_name'; to find out the cluster name.                                                                                                                                 
</longdesc>                                                                                                                                                                                                               
<shortdesc lang="en">Galera cluster name</shortdesc>                                                                                                                                                                      
<content type="string" />                                                                                                                                              
</parameter> 

<parameter name="additional_parameters" unique="0" required="0">
<longdesc lang="en">
Additional parameters to pass on to the Galera arbitrator (garbd)
</longdesc>
<shortdesc lang="en">Additional parameters for the Galera arbitrator</shortdesc>
<content type="string" />
</parameter>

</parameters>

<actions>
<action name="start" timeout="20" />
<action name="stop" timeout="20" />
<action name="status" timeout="20" />
<action name="monitor" timeout="30" interval="20" />
<action name="validate-all" timeout="5" />
<action name="meta-data" timeout="5" />
</actions>
</resource-agent>
END
}

#######################################################################
# Functions invoked by resource manager actions

garbd_check_port() {
# This function has been taken from the squid RA and improved a bit
# The length of the integer must be 4
# Examples of valid port: "1080", "0080"
# Examples of invalid port: "1080bad", "0", "0000", ""

    local int
    local cnt
    
    int="$1"
    cnt=${#int}
    echo $int |egrep -qx '[0-9]+(:[0-9]+)?(,[0-9]+(:[0-9]+)?)*'

    if [ $? -ne 0 ] || [ $cnt -ne 4 ]; then
        ocf_log err "Invalid port number: $1"
        exit $OCF_ERR_CONFIGURED
    fi
}

garbd_validate() {
    local rc

    check_binary $OCF_RESKEY_binary
    check_binary netstat
    garbd_check_port $OCF_RESKEY_donor_port
    
    # A config file on shared storage that is not available
    # during probes is OK.
    if [ ! -f $OCF_RESKEY_config ]; then
        if ! ocf_is_probe; then
            ocf_log err "Config $OCF_RESKEY_config doesn't exist"
            return $OCF_ERR_INSTALLED
        fi
        ocf_log_warn "Config $OCF_RESKEY_config not available during a probe"
    fi

    getent passwd $OCF_RESKEY_user >/dev/null 2>&1
    rc=$?
    if [ $rc -ne 0 ]; then
        ocf_log err "User $OCF_RESKEY_user doesn't exist"
        return $OCF_ERR_INSTALLED
    fi

    true
}

garbd_status() {
    local pid
    local rc

    if [ ! -f $OCF_RESKEY_pid ]; then
        ocf_log info "Galera arbitrator (garbd) is not running"
        return $OCF_NOT_RUNNING
    else
        pid=`cat $OCF_RESKEY_pid`
    fi

    ocf_run -warn kill -s 0 $pid
    rc=$?
    if [ $rc -eq 0 ]; then
        return $OCF_SUCCESS
    else
        ocf_log info "Old PID file found, but Galera arbitrator (garbd) is not running"
        return $OCF_NOT_RUNNING
    fi
}

garbd_monitor() {
    local rc
    local pid
    local garbd_co_check

    garbd_status
    rc=$?

    # If status returned anything but success, return that immediately
    if [ $rc -ne $OCF_SUCCESS ]; then
        return $rc
    fi

    # Check the connections according to the PID.
    # We are sure to hit the garbd process and not other process
    pid=`cat $OCF_RESKEY_pid`
    garbd_co_check=`netstat -punt | grep -s "$OCF_RESKEY_donor_port" | grep -s "$pid" | grep -qs "ESTABLISHED"`
    rc=$?
    if [ $rc -ne 0 ]; then
        ocf_log err "Galera arbitrator is not connected to the database server: $rc"
        return $OCF_NOT_RUNNING
    fi

    ocf_log debug "Galera arbitrator (garbd) monitor succeeded"
    return $OCF_SUCCESS
}

garbd_start() {
    local rc

    garbd_status
    rc=$?
    if [ $rc -eq $OCF_SUCCESS ]; then
        ocf_log info "Galera arbitrator (garbd) already running"
        return $OCF_SUCCESS
    fi

    # run the actual garbd daemon. Don't use ocf_run as we're sending the tool's output
    # straight to /dev/null anyway and using ocf_run would break stdout-redirection here.
    su ${OCF_RESKEY_user} -s /bin/sh -c "${OCF_RESKEY_binary} -a gcomm://$OCF_RESKEY_gcomm_url:$OCF_RESKEY_donor_port -g $OCF_RESKEY_cluster_name \
       $OCF_RESKEY_additional_parameters"' >> /dev/null 2>&1 & echo $!' > $OCF_RESKEY_pid

    # Spin waiting for the server to come up.
    while true; do
    garbd_monitor
    rc=$?
    [ $rc -eq $OCF_SUCCESS ] && break
    if [ $rc -ne $OCF_NOT_RUNNING ]; then
        ocf_log err "Galera arbitrator (garbd) start failed"
        exit $OCF_ERR_GENERIC
    fi
    sleep 1
    done

    ocf_log info "Galera arbitrator (garbd) started"
    return $OCF_SUCCESS
}

garbd_stop() {
    local rc
    local pid

    garbd_status
    rc=$?
    if [ $rc -eq $OCF_NOT_RUNNING ]; then
        ocf_log info "Galera arbitrator (garbd) already stopped"
        return $OCF_SUCCESS
    fi

    # Try SIGTERM
    pid=`cat $OCF_RESKEY_pid`
    ocf_run kill -s TERM $pid
    rc=$?
    if [ $rc -ne 0 ]; then
        ocf_log err "Galera arbitrator (garbd) couldn't be stopped"
        exit $OCF_ERR_GENERIC
    fi

    # stop waiting
    shutdown_timeout=15
    if [ -n "$OCF_RESKEY_CRM_meta_timeout" ]; then
        shutdown_timeout=$((($OCF_RESKEY_CRM_meta_timeout/1000)-5))
    fi
    count=0
    while [ $count -lt $shutdown_timeout ]; do
        garbd_status
        rc=$?
        if [ $rc -eq $OCF_NOT_RUNNING ]; then
            break
        fi
        count=`expr $count + 1`
        sleep 1
        ocf_log debug "Galera arbitrator (garbd) still hasn't stopped yet. Waiting ..."
    done

    garbd_status
    rc=$?
    if [ $rc -ne $OCF_NOT_RUNNING ]; then
        # SIGTERM didn't help either, try SIGKILL
        ocf_log info "Galera arbitrator (garbd) failed to stop after ${shutdown_timeout}s \
          using SIGTERM. Trying SIGKILL ..."
        ocf_run kill -s KILL $pid
    fi

    ocf_log info "Galera arbitrator (garbd) stopped"

    rm -f $OCF_RESKEY_pid

    return $OCF_SUCCESS
}

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

case "$1" in
  meta-data)    meta_data
                exit $OCF_SUCCESS;;
  usage|help)   usage
                exit $OCF_SUCCESS;;
esac

# Anything except meta-data and help must pass validation
garbd_validate || exit $?

# What kind of method was invoked?
case "$1" in
  start)        garbd_start;;
  stop)         garbd_stop;;
  status)       garbd_status;;
  monitor)      garbd_monitor;;
  validate-all) ;;
  *)            usage
                exit $OCF_ERR_UNIMPLEMENTED;;
esac