SAM

AWS Serverless Application Model (SAM) Overview

Overview

AWS SAM is an open-source framework that extends CloudFormation to simplify serverless application development. Here's a comprehensive breakdown:

Key Components

1. Template Specification

# Example SAM Template
AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31

Resources:
  MyFunction:
    Type: AWS::Serverless::Function
    Properties:
      Handler: index.handler
      Runtime: nodejs18.x
      Events:
        ApiEvent:
          Type: Api
          Properties:
            Path: /hello
            Method: get

1. Resource Types

• AWS::Serverless::Function (Lambda)

• AWS::Serverless::Api (API Gateway)

• AWS::Serverless::HttpApi (HTTP API)

• AWS::Serverless::SimpleTable (DynamoDB)

• AWS::Serverless::StateMachine (Step Functions)

• AWS::Serverless::LayerVersion (Lambda Layers)

1. Local Development Features

# Local testing commands
sam local start-api    # Start local API Gateway
sam local invoke      # Test Lambda functions
sam local start-lambda # Start local Lambda endpoint

1. Development Lifecycle

1. Advanced Features

• Policy Templates

  MyFunction:
    Type: AWS::Serverless::Function
    Properties:
      Policies:
        - S3ReadPolicy:
            BucketName: !Ref MyBucket
        - DynamoDBCrudPolicy:
            TableName: !Ref MyTable

• Layers Support

  MyLayer:
    Type: AWS::Serverless::LayerVersion
    Properties:
      ContentUri: ./layer
      CompatibleRuntimes:
        - nodejs18.x

1. Security Features

• Built-in IAM role generation

• Security policy templates

• Integration with AWS security services

1. Development Tools

• SAM CLI for local testing

• AWS Toolkit integration (VS Code, JetBrains, etc.)

• CloudFormation Designer compatibility

1. Best Practices

• Use environment variables for configuration

• Implement proper error handling

• Set appropriate timeouts and memory

• Use layers for shared code

• Enable X-Ray tracing

1. Debugging Capabilities

# Debugging commands
sam logs -n MyFunction    # View logs
sam trace                 # View traces

1. Deployment Options

# Deployment commands
sam deploy --guided      # Interactive deployment
sam deploy --config-file # Use config file

1. Integration Points

• CI/CD pipelines (AWS CodePipeline, GitHub Actions)

• AWS X-Ray for tracing

• CloudWatch for monitoring

• AWS Step Functions for orchestration