Function stop instance

Create Lambda Function to stop instances

1. Access AWS Management Console

• Find Lambda
• Select Lambda

2. In the AWS Lambda interface

• Select Functions
• Select Create function

3. In the Create function interface

• Select Author from scratch
• Function name, enter dc-common-lambda-auto-stop
• Runtime, select Python 3.14

4. Continue in the Create function interface

• Select Change default execution role
• Select Use an existing role
• Select dc-common-lambda-role
• Select Create function

5. After the function is created successfully

• Select Configuration
• Select Environment variables
• Select Edit

6. In the Edit environment variables interface

• Select Add environment variable

7. In the Edit environment variables interface

• Key, enter environment_auto
• Value, enter true

8. After the environment is created successfully

• Select Code

9. In the Code source interface

• Import source code: You need to change the webhook_url to receive notifications to Slack.

import boto3
import os
import json
import logging
import urllib3

logger = logging.getLogger()
logger.setLevel(logging.INFO)

ec2_resource = boto3.resource('ec2')
http = urllib3.PoolManager()
webhook_url = "https://hooks.slack.com/services/XXXXX/XXXXX/XXXXX"  # Replace with your Webhook URL

def lambda_handler(event, context):
    environment_auto = os.environ.get('environment_auto')
    if not environment_auto:
        logger.info('Target is empty')
        return {
            "statusCode": 400,
            "body": "Environment variable 'environment_auto' is not set"
        }

    instances = ec2_resource.instances.filter(
        Filters=[{'Name': 'tag:environment_auto', 'Values': [environment_auto]}]
    )

    instance_list = list(instances)
    if not instance_list:
        return {
            "statusCode": 500,
            "body": "Target Instance is None"
        }

    action_stop = instances.stop()
    send_slack(action_stop)
    return {
        "statusCode": 200,
        "body": "EC2 Stopping"
    }


def send_slack(action_stop):
    list_instance_id = []
    if (
        len(action_stop) > 0
        and "StoppingInstances" in action_stop[0]
        and len(action_stop[0]["StoppingInstances"]) > 0
    ):
        for instance in action_stop[0]["StoppingInstances"]:
            list_instance_id.append(instance["InstanceId"])

        msg = f"Stopping Instances ID:\n {list_instance_id}"
        data = {"text": msg}
        http.request(
            "POST",
            webhook_url,
            body=json.dumps(data).encode("utf-8"),
            headers={"Content-Type": "application/json"}
        )
    else:
        logger.info('Not found Instances Stop')

10. Save and select Deploy

11. Access AWS Management Console

• Find EventBridge
• Select Amazon EventBridge

12. In the Amazon EventBridge interface

• In the left navigation menu, select Schedules (or Scheduler > Schedules)
• Select Create schedule

13. In Step 1: Specify schedule detail

• Schedule name: enter dc-common-lambda-auto-stop
• Description: enter dc-common-lambda-auto-stop
• In the Schedule pattern section:
  • Select Recurring schedule
  • Schedule type: select Rate-based schedule
  • Rate expression: enter 9 and select hours for the unit (or choose a desired interval)
  • For Flexible time window: select Off
• Select Next

14. In Step 2: Select target

• From the list of targets, select AWS Lambda (or search for Lambda Invoke)
• Lambda function: select the dc-common-lambda-auto-stop function created in previous steps
• Select Next

15. In Step 3: Settings

• Keep the default settings (Execution role, Retry policy…)
• Select Next

16. In Step 4: Review and create schedule

• Review all information
• Select Create schedule to complete scheduling the Lambda Function to stop EC2 instances automatically.