Attach TG to ASG after deploy + monitoring

AttachTgToAsgAfterDeploy.sh

#!/bin/sh

get_instance_region() {
    echo $(curl -s http://169.254.169.254/latest/dynamic/instance-identity/document | awk -F '"' '/\"region\"/ { print $4 }')
}

get_instance_id() {
    curl -s http://169.254.169.254/latest/meta-data/instance-id
    return $?
}

get_auto_scaling(){
    echo $(aws autoscaling --region $1 describe-auto-scaling-instances --instance-ids $2 --output text --query AutoScalingInstances[0].AutoScalingGroupName)
}

get_target_group(){
    echo $(aws ec2 describe-tags --region $1 --filters "Name=resource-id,Values=$2" "Name=key,Values=target-group" --output=text | cut -f5)
}

INSTANCE_REGION=$(get_instance_region)
INSTANCE_ID=$(get_instance_id)
AUTO_SCALING=$(get_auto_scaling $INSTANCE_REGION $INSTANCE_ID)
TARGET_GROUP=$(get_target_group $INSTANCE_REGION $INSTANCE_ID)

echo "InstanceId > $INSTANCE_ID"
echo "Region > $INSTANCE_REGION"
echo "ScalingGroup > $AUTO_SCALING"
echo "TargetGroup > $TARGET_GROUP"

if [ -z "$TARGET_GROUP" ]; then
    echo "No target group defined to attach"
else
    TARGET_GROUP_ARN=$(aws elbv2 describe-target-groups --region $INSTANCE_REGION --names $TARGET_GROUP | awk -F '"' '/\"TargetGroupArn\"/ { print $4 }')
    echo "Attaching target-group $TARGET_GROUP ($TARGET_GROUP_ARN) on $AUTO_SCALING..."
    aws autoscaling attach-load-balancer-target-groups --region $INSTANCE_REGION --auto-scaling-group-name $AUTO_SCALING --target-group-arns $TARGET_GROUP_ARN
    echo "Attach finished!"
fi

Monitoring.py

import urllib2, json, boto3

cloudwatch = boto3.client('cloudwatch')
autoscaling = boto3.client('autoscaling')

def registrar_metrica( bad_asgs ):
    cloudwatch.put_metric_data(
        MetricData=[
            {
                'MetricName': 'AutoScalingWithBadHealthCheck',
                'Dimensions': [],
                'Unit': 'None',
                'Value': bad_asgs
            },
        ],
        Namespace='MyCustomAWSMetrics'
    )

def lambda_handler(event, context):
    describe_result = autoscaling.describe_auto_scaling_groups()
    bad_asgs = 0
    for asg in describe_result['AutoScalingGroups']:
        asg_name = asg['AutoScalingGroupName']
        print "\nCheking ASG " + asg_name
        desired_capacity = asg['DesiredCapacity']
        if desired_capacity == 0:
            print "ASG not enabled, skipping..."
            continue
        health_check_type = asg['HealthCheckType']
        if health_check_type != 'ELB':
            print 'ASG with ' + health_check_type + ' health check, expected: ELB'
            bad_asgs += 1
            continue
        tg_count = len(asg['TargetGroupARNs'])
        if tg_count < 1:
            print 'ASG with no TG atacched'
            bad_asgs += 1
            continue
        print 'ASG OK'
    
    print "\nBad ASGs: %d" % bad_asgs
    registrar_metrica( bad_asgs )