AWS Certified Solutions Architect - Associate / Question #1828 of 1019

Question #1828

A company uses an AWS Step Functions workflow to orchestrate its order processing pipeline. The company requires a serverless solution to trigger a third-party inventory management system's HTTP API, which uses username and password authentication, when the workflow completes successfully.

Which solution will meet these requirements?

A

Configure an Amazon EventBridge rule to match AWS Step Functions EXECUTION_SUCCEEDED events. Set up the third-party API as an EventBridge API destination with basic authentication. Assign the API destination as the EventBridge rule target.

B

Create an Amazon EventBridge Scheduler to detect Step Functions EXECUTION_SUCCEEDED events. Configure an AWS Lambda function to invoke the third-party API with username and password credentials. Set the Lambda function as the EventBridge target.

C

Configure the Step Functions workflow to send EXECUTION_SUCCEEDED events to an Amazon API Gateway REST API. Implement an HTTP proxy integration on the API Gateway to directly invoke the third-party API using basic authentication.

D

Configure the Step Functions workflow to publish EXECUTION_SUCCEEDED events to an Amazon SNS topic. Subscribe an AWS Lambda function to the topic, and configure the Lambda function to call the third-party API with username and password authentication.

Explanation

Answer A is correct because:
1. EventBridge Rules: AWS Step Functions emits events (e.g., EXECUTION_SUCCEEDED) to EventBridge. An EventBridge rule can match these events and route them to a target.
2. API Destinations: EventBridge supports API destinations, which allow direct HTTP API calls to third-party endpoints. Basic authentication (username/password) can be configured as part of the API destination's connection.
3. Serverless and Managed: This approach requires no custom code (unlike Lambda in B/D) and avoids unnecessary components like API Gateway (C).

Why other options are incorrect:
- B: EventBridge Scheduler is for time-based triggers, not event-driven workflows. Using Lambda adds unnecessary complexity.
- C: API Gateway requires additional setup (e.g., proxy integration, credentials management) and is less direct than EventBridge API destinations.
- D: While serverless, using Lambda introduces code maintenance overhead when a no-code solution (A) suffices.

Key Points:
- Use EventBridge rules to react to Step Functions events.
- API destinations handle HTTP endpoints with basic auth natively.
- Prefer managed services over custom code when possible.

Answer

The correct answer is: A