AWS Certified Developer – Associate (DVA-C02) — Question 287

A developer is optimizing an AWS Lambda function and wants to test the changes in production on a small percentage of all traffic. The Lambda function serves requests to a RE ST API in Amazon API Gateway. The developer needs to deploy their changes and perform a test in production without changing the API Gateway URL.

Which solution will meet these requirements?

Answer options

• A. Define a function version for the currently deployed production Lambda function. Update the API Gateway endpoint to reference the new Lambda function version. Upload and publish the optimized Lambda function code. On the production API Gateway stage, define a canary release and set the percentage of traffic to direct to the canary release. Update the API Gateway endpoint to use the $LATEST version of the Lambda function. Publish the API to the canary stage.
• B. Define a function version for the currently deployed production Lambda function. Update the API Gateway endpoint to reference the new Lambda function version. Upload and publish the optimized Lambda function code. Update the API Gateway endpoint to use the $LATEST version of the Lambda function. Deploy a new API Gateway stage.
• C. Define an alias on the $LATEST version of the Lambda function. Update the API Gateway endpoint to reference the new Lambda function alias. Upload and publish the optimized Lambda function code. On the production API Gateway stage, define a canary release and set the percentage of traffic to direct to the canary release. Update the API Gateway endpoint to use the $LATEST version of the Lambda function. Publish to the canary stage.
• D. Define a function version for the currently deployed production Lambda function. Update the API Gateway endpoint to reference the new Lambda function version. Upload and publish the optimized Lambda function code. Update the API Gateway endpoint to use the $LATEST version of the Lambda function. Deploy the API to the production API Gateway stage.

Correct answer: C

Explanation

Option C is correct because configuring API Gateway with a canary release on the production stage allows the developer to route a specific percentage of traffic to the $LATEST version of the Lambda function without altering the API Gateway URL. Options A, B, and D fail to properly utilize the API Gateway canary and Lambda alias mechanisms to split traffic, and Option B incorrectly suggests deploying a new stage, which would change the API Gateway URL.