Demo Hands on with AWS Eventbridge schedulers

In this guide, you’ll learn how to use AWS EventBridge to schedule AWS Lambda function invocations. We’ll walk through creating a simple “Hello World” Lambda, setting up a recurring schedule in EventBridge, monitoring invocations, and exploring real-world scenarios.

Prerequisites

• An AWS account with permissions for Lambda and EventBridge
• Basic familiarity with the AWS Management Console

Step 1: Create a Lambda Function

1. Sign in to the AWS Management Console.
2. Navigate to AWS Lambda > Functions > Create function.
3. Choose Blueprint, search for “Hello World,” and select it.
4. Enter a name, e.g., my_lambda.
5. Select Node.js 18.x (or Python 3.x if you prefer).
6. Keep all other settings as default and click Create function.

Step 2: Add the Function Code

1. In the inline editor, replace the default handler with the following Python code:

import json

def lambda_handler(event, context):
    print("loading function")
    return json.dumps(event, indent=2)

2. Click Deploy.

By default, there is no trigger attached. Next, we’ll configure EventBridge.

Step 3: Create an EventBridge Schedule

1. Open the Amazon EventBridge console.
2. In the left pane, choose Schedules > Create schedule.
3. Enter a name (e.g., every-2-minutes) and select Recurring schedule.
4. Under Schedule type, pick Rate-based and set it to Every 2 minutes.
   • You can also use a cron expression under Cron-based if needed.
5. Click Next, disable Enabled, and click Next again.

Step 4: Configure the Schedule Target

1. For Target, choose AWS service > Lambda function.
2. Select your my_lambda function from the dropdown (hit the refresh icon if it doesn’t appear).
3. (Optional) Add a custom JSON payload in the Input section.
4. Click Next, then Create schedule.
5. Finally, enable the schedule to start invoking your function every 2 minutes.

Step 5: Monitor Invocations

1. Go back to the Lambda console and open your my_lambda function.
2. Select the Monitor tab.
3. Adjust the time range to Last 30 minutes (or 15 minutes).
4. You should see invocations every 2 minutes along with logs and metrics.

Scroll down to view individual invocation timestamps and durations.

Common Use Cases

For instance, you could have EventBridge trigger a Lambda that loads a PDF of DevOps headlines from S3 and pushes it to an SNS topic for subscriber email delivery.

Cleanup

To avoid ongoing charges:

1. Delete the my_lambda function in AWS Lambda.
2. Remove your schedule under EventBridge > Schedules.

Links and References

• AWS Lambda Documentation
• Amazon EventBridge Scheduler
• AWS Pricing Calculator