AWS SAM Demystified

Are you intrigued by the concept of serverless computing and the wonders it can bring to your applications? Well, get ready for a mind-blowing adventure into the world of AWS Serverless Application Model (SAM)! In this article, we'll take you on a journey to demystify AWS SAM and explore its key features.

Buckle up and prepare to unleash the magic of serverless development!

Firstly let's start by understanding the essence of AWS SAM. Let's start at the beginning. AWS SAM is a powerful framework designed to simplify the development, testing, and deployment of serverless applications on Amazon Web Services (AWS). It's like having a spellbook filled with pre-defined templates, ready to enchant your applications and take away the complexities of infrastructure management.

AWS SAM is driven by three pillars;

The SAM template is your ticket to serverless stardom. It allows you to describe the AWS resources needed for your application, including functions, event sources, permissions, and more. With its simplified syntax and predefined resource types, you'll be conjuring serverless applications in no time.

 AWSTemplateFormatVersion: '2010-09-09' Transform: AWS::Serverless-2016-10-31 Description: > sam-app Sample SAM Template for sam-app Globals: Function: Timeout: 3 MemorySize: 128 Resources: HelloWorldFunction: Type: AWS::Serverless::Function Properties: CodeUri: hello_world/ Handler: app.lambda_handler Runtime: python3.9 Architectures: - x86_64 Events: HelloWorld: Type: Api Properties: Path: /hello Method: get Outputs: HelloWorldApi: Description: "API Gateway endpoint URL for Prod stage for Hello World function" Value: !Sub "https://${ServerlessRestApi}.execute-api.${AWS::Region}.amazonaws.com/Prod/hello/" HelloWorldFunction: Description: "Hello World Lambda Function ARN" Value: !GetAtt HelloWorldFunction.Arn HelloWorldFunctionIamRole: Description: "Implicit IAM Role created for Hello World function" Value: !GetAtt HelloWorldFunctionRole.Arn 

The SAM CLI (Command Line Interface) is your trusty sidekick in the realm of local development. It enables you to test and debug your serverless applications on your local machine using Docker. You can simulate AWS Lambda and API Gateway locally, sparing you the need to repeatedly deploy your code to AWS during development.

 $ sam local invoke ... {"statusCode": 200, "body": "{\"message\": \"hello world\"}"}% $ sam local start-api ... 2023-06-07 15:07:08 127.0.0.1 - - [07/Jun/2023 15:07:08] "GET /hello HTTP/1.1" 200 - 2023-06-07 15:07:08 127.0.0.1 - - [07/Jun/2023 15:07:08] "GET /favicon.ico HTTP/1.1" 403 - 

With a flick of your wrist, SAM empowers you to package and deploy your serverless applications effortlessly. It bundles your code and dependencies, generating deployment artefacts ready to be deployed using AWS CloudFormation. Deploying your application becomes as simple as casting a spell!

 $ sam deploy --guided Configuring SAM deploy ====================== Looking for config file [samconfig.toml] : Found Reading default arguments : Success Setting default arguments for 'sam deploy' ========================================= Stack Name [sam-app]: hello-world AWS Region [ap-southeast-2]: #Shows you resources changes to be deployed and require a 'Y' to initiate deploy Confirm changes before deploy [Y/n]: #SAM needs permission to be able to create roles to connect to the resources in your template Allow SAM CLI IAM role creation [Y/n]: #Preserves the state of previously provisioned resources when an operation fails Disable rollback [y/N]: HelloWorldFunction may not have authorization defined, Is this okay? [y/N]: y Save arguments to configuration file [Y/n]: n 

AWS SAM embraces the thriving serverless ecosystem by supporting popular programming languages, frameworks, and tools. Whether you're a Python charmer, a Node.js ninja, or a Java guru, SAM has got you covered. It's a gateway to a vibrant community of serverless enthusiasts, who share knowledge and reusable components.

A detailed list of runtimes can be found here - https://docs.aws.amazon.com/lambda/latest/dg/lambda-runtimes.html

And that's it! You've gained a solid foundation to embark on your serverless journey. In this article, we've unravelled the essence of AWS SAM, explored its three pillars, mastered the SAM template, and discovered the joys of local development, packaging, and deployment. Get ready for the next adventure where we'll dive deeper into the mystical world of AWS SAM and uncover more powerful spells for serverless success. Stay curious, keep exploring, and embrace the magic of AWS SAM!