DVA-C02 Development with AWS Services Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Add a Retry clause in the Lambda function's configuration with a maximum retry count of 3.

  Why it's wrong here

  Lambda function configurations do not include a direct retry mechanism for synchronous invocations initiated by services like Step Functions. While Lambda handles retries for asynchronous invocations, Step Functions invokes Lambda synchronously, meaning any retry logic for transient failures must be managed by the caller. Attempting to configure retries within Lambda's settings for this scenario would be ineffective, as the Step Functions state machine is explicitly designed to orchestrate the retry behavior.

• ✓

  Use the Amazon States Language (ASL) Retry field in the Task state definition.

  Why this is correct

  The Amazon States Language (ASL) Retry field is the definitive and recommended mechanism within AWS Step Functions for handling transient failures in Task states. This declarative approach allows developers to specify which error types to retry, the maximum number of attempts, the initial delay, and an exponential backoff rate. Implementing retries directly in the state machine definition ensures robust error handling without modifying the underlying Lambda function code.

• ✗

  Wrap the Lambda function invocation in a custom while loop within the function code.

  Why it's wrong here

  Implementing a custom while loop within the Lambda function code to retry its own operations is an anti-pattern when orchestrated by Step Functions. This approach unnecessarily increases the Lambda function's execution duration and cost, complicates the function's logic, and bypasses Step Functions' native, declarative retry capabilities. It also obscures the state machine's control flow, making error handling less transparent and harder to manage at the orchestration layer.

• ✗

  Use the Amazon States Language Catch field in the Task state to redirect to a retry logic.

  Why it's wrong here

  The Amazon States Language (ASL) Catch field is designed for handling specific errors by transitioning the state machine to a different state, rather than retrying the current one. It serves as an error recovery mechanism, allowing the workflow to gracefully handle unrecoverable failures or errors that have exhausted all defined Retry attempts. While crucial for comprehensive error management, Catch does not implement the retry logic itself; it defines an alternative path after an error occurs or retries are exhausted.

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