AWS-Certified-Developer-Associate Free Practice Test

A company is using an AWS Lambda function to process records from an Amazon Kinesis data stream. The company recently observed slow processing of the records. A developer notices that the iterator age metric for the function is increasing and that the Lambda run duration is constantly above normal.
Which actions should the developer take to increase the processing speed? (Choose two.)

1. A. Increase the number of shards of the Kinesis data stream.
2. B. Decrease the timeout of the Lambda function.
3. C. Increase the memory that is allocated to the Lambda function.
4. D. Decrease the number of shards of the Kinesis data stream.
5. E. Increase the timeout of the Lambda function.

Correct Answer: AC
Increasing the number of shards of the Kinesis data stream will increase the throughput and parallelism of the data processing. Increasing the memory that is allocated to the Lambda function will also increase the CPU and network performance of the function, which will reduce the run duration and improve the processing speed. Option B is not correct because decreasing the timeout of the Lambda function will not affect the processing speed, but may cause some records to fail if they exceed the timeout limit. Option D is not correct because decreasing the number of shards of the Kinesis data stream will decrease the throughput and parallelism of the data processing, which will slow down the processing speed. Option E is not correct because increasing the timeout of the Lambda function will not affect the processing speed, but may increase the cost of running the function.
References: [Amazon Kinesis Data Streams Scaling], [AWS Lambda Performance Tuning]

A company uses Amazon API Gateway to expose a set of APIs to customers. The APIs have caching enabled in API Gateway. Customers need a way to invalidate the cache for each API when they test the API.
What should a developer do to give customers the ability to invalidate the API cache?

1. A. Ask the customers to use AWS credentials to call the InvalidateCache API operation.
2. B. Attach an InvalidateCache policy to the IAM execution role that the customers use to invoke the AP
3. C. Ask the customers to send a request that contains the HTTP header when they make an API call.
4. D. Ask the customers to use the AWS SDK API Gateway class to invoke the InvalidateCache API operation.
5. E. Attach an InvalidateCache policy to the IAM execution role that the customers use to invoke the AP
6. F. Ask the customers to add the INVALIDATE_CACHE query string parameter when they make an API call.

Correct Answer: D

A company is developing an ecommerce application that uses Amazon API Gateway APIs. The application uses AWS Lambda as a backend. The company needs to test the code in a dedicated, monitored test environment before the company releases the code to the production environment.
When solution will meet these requirements?

1. A. Use a single stage in API Gatewa
2. B. Create a Lambda function for each environmen
3. C. Configure API clients to send a query parameter that indicates the endowment and the specific lambda function.
4. D. Use multiple stages in API Gatewa
5. E. Create a single Lambda function for all environment
6. F. Add different code blocks for different environments in the Lambda function based on Lambda environments variables.
7. G. Use multiple stages in API Gatewa
8. H. Create a Lambda function for each environmen
9. I. Configure API Gateway stage variables to route traffic to the Lambda function in different environments.
10. J. Use a single stage in API Gatewa
11. K. Configure a API client to send a query parameter that indicated the environmen
12. L. Add different code blocks tor afferent environments in the Lambda Junction to match the value of the query parameter.

Correct Answer: C
The solution that will meet the requirements is to use multiple stages in API Gateway. Create a Lambda function for each environment. Configure API Gateway stage variables to route traffic to the Lambda function in different environments. This way, the company can test the code in a dedicated, monitored test environment before releasing it to the production environment. The company can also use stage variables to specify the Lambda function version or alias for each stage, and avoid hard-coding the Lambda function name in the API Gateway integration. The other options either involve using a single stage in API Gateway, which does not allow testing in different environments, or adding different code blocks for different environments in the Lambda function, which increases complexity and maintenance.
Reference: Set up stage variables for a REST API in API Gateway

A developer is building a serverless application by using AWS Serverless Application Model (AWS SAM) on multiple AWS Lambda functions. When the application is deployed, the developer wants to shift 10% of the traffic to the new deployment of the application for the first 10 minutes after deployment. If there are no issues, all traffic must switch over to the new version.
Which change to the AWS SAM template will meet these requirements?

1. A. Set the Deployment Preference Type to Canaryl OPercent10Minute
2. B. Set the AutoPublishAlias property to the Lambda alias.
3. C. Set the Deployment Preference Type to Linearl OPercentEveryIOMinute
4. D. Set AutoPubIishAIias property to the Lambda alias.
5. E. Set the Deployment Preference Type to Canaryl OPercentIOMinute
6. F. Set the PreTraffic and PostTraffic properties to the Lambda alias.
7. G. Set the Deployment Preference Type to Linearl OPercentEvery10Minute
8. H. Set PreTraffic and PostTraffic properties to the Lambda alias.

Correct Answer: A
✑ The Deployment Preference Type property specifies how traffic should be shifted between versions of a Lambda function1. The Canary10Percent10Minutes option means that 10% of the traffic is immediately shifted to the new version, and after 10 minutes, the remaining 90% of the traffic is shifted1. This matches the requirement of shifting 10% of the traffic for the first 10 minutes, and then switching all traffic to the new version.
✑ The AutoPublishAlias property enables AWS SAM to automatically create and update a Lambda alias that points to the latest version of the function1. This is required to use the Deployment Preference Type property1. The alias name can be specified by the developer, and it can be used to invoke the function with the latest code.

A developer is configuring an applications deployment environment in AWS CodePipeine. The application code is stored in a GitHub repository. The developer wants to ensure that the repository package's unit tests run in the new deployment environment. The deployment has already set the pipeline's source provider to GitHub and has specified the repository and branch to use in the deployment.
When combination of steps should the developer take next to meet these requirements with the least the LEAST overhead' (Select TWO).

1. A. Create an AWS CodeCommt projec
2. B. Add the repository package's build and test commands to the protects buildspec
3. C. Create an AWS CodeBuid projec
4. D. Add the repository package's build and testcommands to the projects buildspec
5. E. Create an AWS CodeDeploy protec
6. F. Add the repository package's build and test commands to the project's buildspec
7. G. Add an action to the source stag
8. H. Specify the newly created project as the action provide
9. I. Specify the build attract as the actions input artifact.
10. J. Add a new stage to the pipeline alter the source stag
11. K. Add an action to the new stag
12. L. Speedy the newly created protect as the action provide
13. M. Specify the source artifact as the action's input artifact.

Correct Answer: BE
This solution will ensure that the repository package’s unit tests run in the new deployment environment with the least overhead because it uses AWS CodeBuild to build and test the code in a fully managed service, and AWS CodePipeline to orchestrate the deployment stages and actions. Option A is not optimal because it will use AWS CodeCommit instead of AWS CodeBuild, which is a source control service, not a build and test service. Option C is not optimal because it will use AWS CodeDeploy instead of AWS CodeBuild, which is a deployment service, not a build and test service. Option D is not optimal because it will add an action to the source stage instead of creating a new stage, which will not follow the best practice of separating different deployment phases. References: AWS CodeBuild, AWS CodePipeline