DVA-C02 Question 238
Single answerYou are developing an application that uses AWS Lambda functions and interacts with an Amazon DynamoDB table. During the development phase, you need to test the Lambda function locally to ensure it performs as expected before deploying it to the production environment. Which approach should you use to simulate the production environment as closely as possible?
- A
Use the AWS SAM CLI to invoke the Lambda function locally with test events and connect it to a locally running DynamoDB instance.
- B
Deploy the Lambda function to a development environment in AWS and test it directly using the AWS Management Console.
- C
Set up a Docker container with an AWS Lambda runtime environment and DynamoDB Local for testing.
- D
Use the AWS CLI to invoke the Lambda function directly in the production environment to test its behavior.
Show answer and explanation
Correct answer: A
Explanation
The AWS SAM CLI is a powerful tool for testing serverless applications locally during development. It allows you to simulate the Lambda runtime environment and connect to services like DynamoDB Local, providing a cost-effective and safe way to test applications before deployment. This ensures that the application behaves as expected without impacting production resources or incurring additional costs.
- A. Correct.
This is the correct answer. The AWS Serverless Application Model (SAM) CLI allows developers to simulate the Lambda runtime locally while also interacting with services like DynamoDB Local, which is a useful tool for testing during development.
- B. Incorrect.
While deploying to a development environment in AWS is a valid approach for testing, it is not the most suitable option during early development when local testing is sufficient.
- C. Incorrect.
Although Docker can be used to mimic an AWS Lambda runtime environment, it adds unnecessary complexity compared to a tool like AWS SAM CLI, which is specifically designed for local testing.
- D. Incorrect.
Testing directly in the production environment is not recommended as it can lead to unintended consequences, such as data corruption or unexpected costs.