SAA-C03 Question 116
Select 3A company is designing an event-driven architecture to process customer orders. When an order is placed, the system should validate the order, charge the customer, and then send a confirmation email. These actions should be decoupled so that failures in one action do not affect the others. Which combination of AWS services should the company use to implement this architecture?
- A
Amazon SQS to decouple components and Amazon Lambda to process events
- B
Amazon SNS to fan out messages to multiple subscribers and Amazon Lambda to process events
- C
Amazon RDS to store the order data and Amazon EC2 to validate and process the orders
- D
Amazon DynamoDB Streams to trigger downstream processing and Amazon Lambda for serverless compute
- E
AWS Step Functions to orchestrate the workflow and Amazon EC2 to run tasks
Show answer and explanation
Correct answers: A, B, D
Explanation
Event-driven architectures rely on services that decouple components and asynchronously process events. Amazon SQS and SNS are core messaging services that facilitate decoupling and event distribution. Amazon DynamoDB Streams allows capturing and processing changes to database items in an event-driven manner. These services, combined with Amazon Lambda's serverless compute capabilities, enable the company to process customer orders asynchronously and independently. Other options, like Amazon RDS or EC2, do not provide the required decoupling or event-driven capabilities.
- A. Correct.
Amazon SQS is a fully managed message queue service that can be used to decouple components in an event-driven architecture. Amazon Lambda can process events from SQS queues, making this a viable option.
- B. Correct.
Amazon SNS is a publish/subscribe service that allows messages to be delivered to multiple subscribers. Combined with Amazon Lambda, it supports event-driven architectures by fanning out messages to multiple processing functions.
- C. Incorrect.
Amazon RDS is a relational database service and Amazon EC2 is an infrastructure service. While RDS can store order data and EC2 can process it, this combination does not inherently support an event-driven architecture as it lacks the decoupling and event-handling capabilities of services like SQS, SNS, or Lambda.
- D. Correct.
Amazon DynamoDB Streams capture changes to items in DynamoDB tables, which can trigger downstream processing using Amazon Lambda. This supports an event-driven architecture with decoupling and serverless processing.
- E. Incorrect.
AWS Step Functions is a workflow orchestration service, but it is not designed specifically for event-driven architectures. Amazon EC2 is also not a serverless or decoupled compute option for this use case.