Put linux process status to Amazon CloudWatch.

put-process-status.sh

###################################################################################
# check process aliving (count process number)
# return integer 1 (process is running) or 0 (process is dead) or 9 (some error)
###################################################################################
function is_process_alive() {
    count=`ps awux | grep -v grep | grep -v "$0" | grep -w "$1" | wc -l`
    if [[ $count =~ ^[0-9]+$ ]]; then
        if [ $count != 0 ]; then
            echo 1
        else
            echo 0
        fi
    else
        echo 9
    fi
}

## instance config
readonly INSTANCE_ID=`curl -s http://169.254.169.254/latest/meta-data/instance-id`
readonly REGION='ap-northeast-1'

## config
readonly NAMESPACE='CustomMetrics'
readonly UNIT='Count'
if [ $# -ne 1 ]; then
    echo '[ERROR] invalid paramter'
    exit 1;
fi

process_name=$1
if [ $process_name = '' ]; then
    echo '[ERROR] process name is required'
    exit 1;
fi

metrics_name="process/$process_name"

## process count
value=`is_process_alive $@`

if [ $value -ne 1 ] && [ $value -ne 0 ]; then
    echo '[ERROR] failed to count process number'
    exit 1;
fi

## put data to CloudWatch
aws cloudwatch put-metric-data --metric-name $metrics_name --namespace $NAMESPACE --value $value --region $REGION --unit $UNIT --dimensions "InstanceId=$INSTANCE_ID,ProcessName=$process_name"