EventBridge to Lambda - AWS SAM Application

Overview

This project demonstrates how to create a serverless application using AWS SAM. It includes an AWS Lambda function triggered by an EventBridge rule. The Lambda function logs incoming events to AWS CloudWatch Logs.

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Prerequisites

Before you begin, ensure you have the following tools installed:

1. AWS SAM CLI: Install AWS SAM CLI

2. AWS CLI: Install AWS CLI and configure it with your AWS credentials:

   aws configure

3. Python: Ensure Python 3.13 or a compatible runtime is installed. Add it to your PATH if not already.

4. Docker (Optional): For container-based builds, install Docker Desktop.

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Application Architecture

• Event Source: Amazon EventBridge listens for events matching a specific pattern.
• Lambda Function: A Lambda function is triggered by EventBridge and logs the event details to CloudWatch Logs.
• CloudWatch Logs: Captures and stores the logs from the Lambda function.

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Setup Instructions

1. Clone the Repository

git clone https://github.com/insighture/eventbridge-lambda.git
cd eventbridge-lambda

2. Build the Application

sam build

3. Deploy the Application

Deploy the application to your AWS account:

sam deploy --guided

During deployment, you will be prompted for:

• Stack Name: Enter a name for your stack (e.g., eventbridge-lambda-app).
• AWS Region: Choose your preferred AWS region.
• Other Configurations: Accept the defaults or customize as needed.

The deployment will create an EventBridge rule, Lambda function, and necessary permissions.

4. Test the Application

Manually Trigger an Event

Send a test event to EventBridge using the AWS CLI:

aws events put-events --entries '[{
  "Source": "custom.myapp",
  "DetailType": "MyApp Event",
  "Detail": "{\"status\": \"trigger\"}"
}]'

Verify Logs

1. Go to the CloudWatch Logs console in the AWS Management Console.
2. Find the log group for your Lambda function (e.g., /aws/lambda/HelloWorldFunction).
3. View the logs to see the received event details.

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Cleanup

To avoid incurring charges, delete the stack:

sam delete

This will remove all resources created by the application.

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Lambda Function Code

The Lambda function logs the incoming event details:

import logging

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

def lambda_handler(event, context):
    logger.info("Event received from EventBridge!")
    logger.info(f"Event details: {event}")
    return {
        "statusCode": 200,
        "body": "Hello, EventBridge!"
    }

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SAM Template

The template.yaml defines the Lambda function and EventBridge rule:

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: SAM Template for EventBridge Hello World

Resources:
  HelloWorldFunction:
    Type: AWS::Serverless::Function
    Properties:
      Handler: app.lambda_handler
      Runtime: python3.13
      CodeUri: hello_world/
      Policies:
        - CloudWatchLogsFullAccess
      Events:
        EventBridgeRule:
          Type: CloudWatchEvent
          Properties:
            Pattern:
              source:
                - "custom.myapp"
              detail-type:
                - "MyApp Event"
              detail:
                status:
                  - "trigger"

  EventBridgeRule:
    Type: AWS::Events::Rule
    Properties:
      Name: MyEventBridgeRule
      EventPattern:
        source:
          - "custom.myapp"
        detail-type:
          - "MyApp Event"
        detail:
          status:
            - "trigger"
      Targets:
        - Arn: !GetAtt HelloWorldFunction.Arn
          Id: "HelloWorldFunctionTarget"

  LambdaInvokePermission:
    Type: AWS::Lambda::Permission
    Properties:
      Action: lambda:InvokeFunction
      FunctionName: !GetAtt HelloWorldFunction.Arn
      Principal: events.amazonaws.com
      SourceArn: !GetAtt EventBridgeRule.Arn

Outputs:
  HelloWorldFunction:
    Description: Lambda Function ARN
    Value: !GetAtt HelloWorldFunction.Arn

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License

N/A