#!/bin/bash
#
# Queue manager script, to make sure the required number of worker instances
# are running. Schedule this in cron to make sure any crashed workers will
# be restarted.
#

# Get the full path to ourselfs
SCRIPTPATH="$( dirname "$( which "$0" )" )"

# how many workers do we need to start?
if [ $# -gt 0 ]; then
    WORKERS=$1
else
    WORKERS=1;
fi

# where does the php binary live?
PHP=`which php`

# command that starts the worker
COMMAND="$SCRIPTPATH/../../../oil refine queueworker"

# loop to process the worker instantiation
while :
do
        # bail out if we have started enough workers
        PROCESS_COUNT=`pgrep -f "$COMMAND" | wc -l`
        if [ $PROCESS_COUNT -eq $WORKERS ]; then
                exit 0
        fi

        # too many workers running?
        if [ $PROCESS_COUNT -gt $WORKERS ]; then
            # kill a worker off nicely
            PROCESS=`pgrep -f -n "$COMMAND"`
            kill -15 $PROCESS
            sleep 1
        else
            # start a new worker
            $PHP $COMMAND &
        fi
done