AWS Certified DevOps Engineer – Professional (DOP-C02) — Question 340

A DevOps engineer manages an AWS CodePipeline pipeline that builds and deploys a web application on AWS. The pipeline has a source stage, a build stage, and a deploy stage. When deployed properly, the web application responds with a 200 OK HTTP response code when the URL of the home page is requested.

The home page recently returned a 503 HTTP response code after CodePipeline deployed the application. The DevOps engineer needs to add an automated test into the pipeline. The automated test must ensure that the application returns a 200 OK HTTP response code after the application is deployed. The pipeline must fail if the response code is not present during the test. The DevOps engineer has added a CheckURL stage after the deploy stage in the pipeline.

What should the DevOps engineer do next to implement the automated test?

Answer options

• A. Configure the CheckURL stage to use an Amazon CloudWatch action. Configure the action to use a canary synthetic monitoring check on the application URL and to report a success or failure to CodePipeline.
• B. Create an AWS Lambda function to check the response code status of the URL and to report a success or failure to CodePipeline. Configure an action in the CheckURL stage to invoke the Lambda function.
• C. Configure the CheckURL stage to use an AWS CodeDeploy action. Configure the action with an input artifact that is the URL of the application and to report a success or failure to CodePipeline.
• D. Deploy an Amazon API Gateway HTTP API that checks the response code status of the URL and that reports success or failure to CodePipeline. Configure the CheckURL stage to use the AWS Device Farm test action and to provide the API Gateway HTTP API as an input artifact.

Correct answer: B

Explanation

To perform custom validation in an AWS CodePipeline stage, invoking an AWS Lambda function is the standard and most direct approach. The Lambda function can send an HTTP request to the application URL, inspect the response code, and then use the CodePipeline API (specifically PutJobSuccessResult or PutJobFailureResult) to report the outcome back to the pipeline. Other options like CloudWatch, CodeDeploy, or Device Farm are not designed to natively perform this type of simple web request validation and report the results directly to CodePipeline.