Exam 6: AWS Certified Developer Associate (DVA-C01)

A Developer is creating a Lambda function that will generate and export a file. The function requires 100 MB of temporary storage for temporary files while executing. These files will not be needed after the function is complete. How can the Developer MOST efficiently handle the temporary files?

A company has a web application that uses an Amazon Cognito user pool for authentication. The company wants to create a login page with the company logo. What should a Developer do to meet these requirements?

Company A has an S3 bucket containing premier content that they intend to make available to only paid subscribers of their website. The S3 bucket currently has default permissions of all objects being private to prevent inadvertent exposure of the premier content to non-paying website visitors. How can Company A provide only paid subscribers the ability to download a premier content file in the S3 bucket?

A gaming company is developing a mobile game application for iOS® and Android® platforms. This mobile game securely stores user data locally on the device. The company wants to allow users to use multiple device for the game, which requires user data synchronization across device. Which service should be used to synchronize user data across devices without the need to create a backend application?

Where should the appspec.yml file be placed in order for AWS CodeDeploy to work?

A developer is building an application integrating an Amazon API Gateway with an AWS Lambda function. When calling the API, the developer receives the following error: Wed Nov 08 01:13:00 UTC 2017 : Method completed with status: 502 What should the developer do to resolve the error?

A company's website runs on an Amazon EC2 instance and uses Auto Scaling to scale the environment during peak times. Website users across the world are experiencing high latency due to static content on the EC2 instance, even during non-peak hours. Which combination of steps will resolve the latency issue? (Choose two.)

An application is expected to process many files. Each file takes four minutes to process each AWS Lambda invocation. The Lambda function does not return any important data. What is the fastest way to process all the files?

A Developer wants to debug an application by searching and filtering log data. The application logs are stored in Amazon CloudWatch Logs. The Developer creates a new metric filter to count exceptions in the application logs. However, no results are returned from the logs. What is the reason that no filtered results are being returned?

A company developed a set of APIs that are being served through the Amazon API Gateway. The API calls need to be authenticated based on OpenID identity providers such as Amazon or Facebook. The APIs should allow access based on a custom authorization model. Which is the simplest and MOST secure design to use to build an authentication and authorization model for the APIs?

A company needs to secure its existing website running behind an Elastic Load Balancer. The website's Amazon EC2 instances are CPU-constrained. What should be done to secure the website while not increasing the CPU load on the EC2 web servers? (Choose two.)

A company is building a stock trading application that requires sub-millisecond latency in processing trading requests. Amazon DynamoDB is used to store all the trading data that is used to process each request. After load testing the application, the development team found that due to data retrieval times, the latency requirement is not satisfied. Because of sudden high spikes in the number of requests, DynamoDB read capacity has to be significantly over-provisioned to avoid throttling. What steps should be taken to meet latency requirements and reduce the cost of running the application?

A Developer has an e-commerce API hosted on Amazon ECS. Variable and spiking demand on the application is causing order processing to take too long. The application processes Amazon SQS queues. The ApproximateNumberOfMessagesVisible metric spikes at very high values throughout the day, which cause Amazon CloudWatch alarm breaches. Other ECS metrics for the API containers are well within limits. What can the Developer implement to improve performance while keeping costs low?

A Developer created a Lambda function for a web application backend. When testing the Lambda function from the AWS Lambda console, the Developer can see that the function is being executed, but there is no log data being generated in Amazon CloudWatch Logs, even after several minutes. What could cause this situation?

A Developer has a stateful web server on-premises that is being migrated to AWS. The Developer must have greater elasticity in the new design. How should the Developer re-factor the application to make it more elastic? (Choose two.)

A developer must ensure that the IAM credentials used by an application in Amazon EC2 are not misused or compromised. What should the developer use to keep user credentials secure?

A legacy service has an XML-based SOAP interface. The Developer wants to expose the functionality of the service to external clients with the Amazon API Gateway. Which technique will accomplish this?

What happens, by default, when one of the resources in a CloudFormation stack cannot be created?

A company has written a Java AWS Lambda function to be triggered whenever a user uploads an image to an Amazon S3 bucket. The function converts the original image to several different formats and then copies the resulting images to another Amazon S3 bucket. The Developers find that no images are being copied to the second Amazon S3 bucket. They have tested the code on an Amazon EC2 instance with 1GB of RAM, and it takes an average of 500 seconds to complete. What is the MOST likely cause of the problem?

A Development team currently supports an application that uses an in-memory store to save accumulated game results. Individual results are stored in a database. As part of migrating to AWS, the team needs to use automatic scaling. The team knows this will yield inconsistent results. Where should the team store these accumulated game results to BEST allow for consistent results without impacting performance?