AWS Certified Developer Associate · Free Practice Question Medium
Question 42
A developer is creating a serverless web application that includes AWS Lambda functions and a REST API deployed using Amazon API Gateway. The developer maintains multiple branches of code. The developer wants to avoid updating the API gateway target endpoint when a new code push is performed.
What solution would allow the developer to update the Lambda code without needing to update the REST API configuration?
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A
Create multiple stages and deployments.
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B
Create aliases and versions in AWS Lambda.
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C
Create multiple private API endpoints and use CNAMEs.
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D
Create different tags for each Lambda function.
Reveal correct answer
Correct answer: B
Explanation
You can create one or more aliases for your Lambda function. A Lambda alias is like a pointer to a specific function version. Users can access the function version using the alias Amazon Resource Name (ARN). You can then release new versions of your code without needing to change the alias that applications use to invoke the function.
In this case the REST API could be configured with aliases for the functions. The developer could also use different stages with different endpoints using the aliases. This would enable calling different versions of the application by changing the stage name in the REST API URL.
CORRECT: "Create aliases and versions in AWS Lambda" is the correct answer (as explained above.)
INCORRECT: "Create multiple stages and deployments" is incorrect.
Stages and stage variables could be used to reference different functions or aliases. But if only stages and deployments are used (and not a Lambda alias) then the REST API would need to have the endpoint updated every time a new function version is released.
INCORRECT: "Create different tags for each Lambda function" is incorrect.
Tags cannot be used to define the Lambda endpoints in the REST API.
INCORRECT: "Create multiple private API endpoints and use CNAMEs" is incorrect.
There is no value here in creating multiple private API endpoints as that would be completely different APIs.
References:
https://docs.aws.amazon.com/lambda/latest/dg/configuration-aliases.html
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