AWS Certified Solutions Architect – Associate (SAA-C03) — Question 528

A company needs to integrate with a third-party data feed. The data feed sends a webhook to notify an external service when new data is ready for consumption. A developer wrote an AWS Lambda function to retrieve data when the company receives a webhook callback. The developer must make the Lambda function available for the third party to call.

Which solution will meet these requirements with the MOST operational efficiency?

Answer options

• A. Create a function URL for the Lambda function. Provide the Lambda function URL to the third party for the webhook.
• B. Deploy an Application Load Balancer (ALB) in front of the Lambda function. Provide the ALB URL to the third party for the webhook.
• C. Create an Amazon Simple Notification Service (Amazon SNS) topic. Attach the topic to the Lambda function. Provide the public hostname of the SNS topic to the third party for the webhook.
• D. Create an Amazon Simple Queue Service (Amazon SQS) queue. Attach the queue to the Lambda function. Provide the public hostname of the SQS queue to the third party for the webhook.

Correct answer: A

Explanation

Creating a Lambda function URL is the most operationally efficient solution because it provides a built-in HTTPS endpoint for the function without requiring the configuration or management of external resources. Using an Application Load Balancer adds unnecessary complexity and cost for a simple webhook integration. Amazon SNS and Amazon SQS cannot directly receive external HTTP/HTTPS webhook requests without additional proxying infrastructure.