DEA-C01 Question 308
Select 2You are building a data processing application on AWS that processes large datasets in real-time and integrates with an external system via an API. The application must handle high request rates and ensure scalability and fault tolerance. Which combination of services and approaches should you use for making API calls to the external system?
- A
Use AWS Lambda for making API calls and configure an Amazon SQS queue to decouple the API requests.
- B
Use an Amazon EC2 instance with a cron job to batch API requests and retry failed calls.
- C
Use AWS Step Functions to orchestrate and retry API calls to the external system.
- D
Directly invoke the external API from your application running on AWS Fargate without any intermediate service.
- E
Implement an Amazon SNS topic to fan out API requests to multiple subscribers.
Show answer and explanation
Correct answers: A, C
Explanation
To handle high request rates, scalability, and fault tolerance when integrating with an external API, it is best to use a combination of AWS services that support decoupling and error handling. AWS Lambda with an Amazon SQS queue enables asynchronous and reliable API calls, while AWS Step Functions provides orchestration and retry logic for complex workflows. These options are specifically designed for scalable and fault-tolerant architectures.
- A. Correct.
Correct. Using AWS Lambda along with an Amazon SQS queue ensures that API requests are decoupled, scalable, and fault-tolerant. SQS queues can handle high request rates and ensure reliable message delivery.
- B. Incorrect.
Incorrect. While EC2 can batch process API requests, it lacks the inherent scalability and fault tolerance that services like Lambda and SQS provide. Managing retries manually is also less efficient.
- C. Correct.
Correct. AWS Step Functions is a serverless orchestration service that can manage retries, error handling, and sequencing of API calls, making it a good choice for handling complex workflows.
- D. Incorrect.
Incorrect. Directly invoking the external API from AWS Fargate without any intermediate service introduces tight coupling and does not inherently handle retries or scaling.
- E. Incorrect.
Incorrect. Amazon SNS is designed for fan-out messaging and is not suitable for reliably managing API calls to an external system.