Serverless Application Model (SAM) in AWS - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Architecture

intermediate

Understanding AWS SAM Template Structure

Given the following AWS SAM template snippet, what resource type is being defined?

Resources:
  MyFunction:
    Type: AWS::Serverless::Function
    Properties:
      Handler: index.handler
      Runtime: nodejs14.x
      CodeUri: ./src
      Events:
        ApiEvent:
          Type: Api
          Properties:
            Path: /hello
            Method: get

A An Amazon DynamoDB table with a primary key

B An Amazon SNS topic for messaging

C An Amazon S3 bucket configured for static website hosting

D An AWS Lambda function triggered by an API Gateway HTTP GET request

💡 Hint

Look at the Type and Events sections to identify the resource.

The resource type AWS::Serverless::Function defines a Lambda function. The Events section shows it is triggered by an API Gateway event on the GET method at path /hello.

❓ service_behavior

intermediate

SAM Deployment Behavior with CodeUri

When deploying an AWS SAM application, what happens if the CodeUri property points to a local directory?

A SAM packages the local code directory into a deployment artifact and uploads it to an S3 bucket automatically

B SAM directly uploads the local directory contents to the Lambda function without packaging

C SAM requires the user to manually upload the code to S3 before deployment

D SAM ignores the <code>CodeUri</code> and deploys an empty Lambda function

💡 Hint

Think about how SAM handles local code during deployment.

SAM automatically packages the local code directory specified in CodeUri into a zip file and uploads it to an S3 bucket during deployment.

❓ security

advanced

IAM Role Configuration in SAM

In an AWS SAM template, if you want to restrict a Lambda function's permissions to only read items from a specific DynamoDB table, which of the following IAM policy snippets correctly achieves this?

Policies:
  - Version: '2012-10-17'
    Statement:
      - Effect: Allow
        Action: dynamodb:GetItem
        Resource: arn:aws:dynamodb:us-east-1:123456789012:table/MyTable

A The policy allows all DynamoDB actions on all tables in the account

B The policy allows GetItem on all DynamoDB tables in the region

C The policy allows only the GetItem action on the specified DynamoDB table resource

D The policy denies all DynamoDB actions on the specified table

💡 Hint

Check the Action and Resource fields carefully.

The policy explicitly allows only the dynamodb:GetItem action on the specified table ARN, restricting permissions as intended.

❓ Configuration

advanced

SAM Template Environment Variables Configuration

Which of the following SAM template snippets correctly sets environment variables for a Lambda function?

Resources:
  MyFunction:
    Type: AWS::Serverless::Function
    Properties:
      Handler: app.lambda_handler
      Runtime: python3.9
      Environment:
        Variables:
          STAGE: prod
          LOG_LEVEL: debug

A Environment variables must be set outside the Properties section

B The environment variables STAGE and LOG_LEVEL are correctly set for the Lambda function

C The environment variables are incorrectly nested and will cause a deployment error

D SAM does not support environment variables in Lambda functions

💡 Hint

Review the correct placement of environment variables in SAM templates.

Environment variables are set under Properties.Environment.Variables in the SAM template, as shown, which is correct.

✅ Best Practice

expert

Optimizing SAM Template for Multiple Environments

You want to deploy the same SAM application to multiple environments (dev, test, prod) with different configuration values like memory size and environment variables. Which approach follows best practices?

A Use one SAM template with parameterized values and pass environment-specific parameters during deployment

B Use separate SAM templates for each environment with duplicated resources and values

C Hardcode all environment values in the SAM template and manually edit before each deployment

D Deploy the SAM application once and manually change configuration in the AWS Console for each environment

💡 Hint

Think about maintainability and automation when managing multiple environments.

Using parameters in a single SAM template allows you to reuse the template and pass different values per environment, which is a best practice for maintainability and automation.