You work for a car rental firm in their car tracking department. Your team is responsible for building machine learning solutions to track the company`s fleet of cars. Each car is equipped with a GPS vehicle tracking device that emits IoT data. You are building a data transformation solution to take the GPS IoT data and transform it before storing it in S3 for use in your machine learning models.
You have decided to use Kinesis Data Firehose data transformation to pre-process your IoT data before storing it in S3. You have written your lambda function that pre-processes the data, and you are now testing your data transformation process flow. When running your tests, you see that Kinesis Data Firehose rejects every record as a data transformation failure. What could be the reason for the failure?

Answer options:

A.In your Lambda function, you have set the result to OK or Dropped for each record processed.
B.The transformed records from your lambda function consist of the recordId and result parameters.
C.When creating your Lambda function, you used a lambda blueprint for data transformation from the AWS Serverless Application Repository.
D.When creating your Lambda function, you used a lambda blueprint for data transformation from the AWS Lambda console.

Answer: B
Option A is incorrect. The status of your transformed record produced by your lambda function can be Ok (the record was transformed successfully), Dropped (the record was dropped intentionally by your transformation logic), or ProcessingFailed (the record could not be transformed). A status of Ok or Dropped indicates to Kinesis Data Firehose that the record was successfully processed. A status of ProcessingFailed indicates a failed transformation. Your lambda function has set each record’s status to either Ok or Dropped, so this option is incorrect.
Option B is correct. Transformed records received by Kinesis Data Firehose from lambda must contain the recordId, result, and data parameters. Your transformed records only contain the recordId and result parameters.
Option C is incorrect. You can use lambda blueprints from either the AWS Serverless Application Repository or the AWS Lambda console to create your transformation lambda function.
Option D is incorrect. You can use lambda blueprints from either the AWS Serverless Application Repository or the AWS Lambda console to create your transformation lambda function.
Reference:
Please see the Amazon Kinesis Data Firehose developer guide titled Amazon Kinesis Data Firehose Data Transformation.