Porting your web app to serverless in 30 minutes [Collision @ Toronto]

This live-coding session will guide you through the process of migrating an existing Express application to AWS Lambda. We will analyze the existing application, decompose it into Lambda functions, reshape the frontend as a static website, and finally deploy it to the Cloud. Throughout this step-by-step process, you will learn the benefits of serverless and how it will change the way you think of scalability, availability, security, infrastructure management, and cost optimization.

Transcript

1. Alex Casalboni Technical Evangelist, AWS @alex_casalboni Porting your web app to serverless in 30 minutes is how @ 2019, Amazon Web Services, Inc. or its Affiliates. All rights reserved
2. About me • Software Engineer & Web Developer • Worked in a startup for 4.5 years • ServerlessDays Organizer • AWS Customer since 2013
3. Agenda 1. Why serverless computing 2. Choosing a programming language 3. Live coding (app migration)
4. Why serverless computing
5. No server or container management Flexible scaling No idle capacity $ High availability
6. Event-driven architectures Services (anything) Event source Serverless Function
7. Common Use Cases Web apps • Static websites • Complex web apps • Packages for Flask and Express Data processing • Real time • MapReduce • Batch • Machine learning inference Chatbots • Powering chatbot logic Backends • Apps and services • Mobile • IoT </> </> Amazon Alexa • Powering voice-enabled apps • Alexa Skills Kit IT automation • Policy engines • Extending AWS services • Infrastructure management
8. AWS Serverless Application Model (SAM) Simplified template-driven deployment model for serverless applications New serverless resource types An extension (Macro) of AWS CloudFormation Open specification (Apache 2.0) github.com/awslabs/serverless-application-model
9. AWSTemplateFormatVersion: '2010-09-09' Resources: GetHtmlFunctionGetHtmlPermissionProd: Type: AWS::Lambda::Permission Properties: Action: lambda:invokeFunction Principal: apigateway.amazonaws.com FunctionName: Ref: GetHtmlFunction SourceArn: Fn::Sub: arn:aws:execute-api:${AWS::Region}:${AWS::AccountId}:${ServerlessRestApi}/Prod/ANY/* ServerlessRestApiProdStage: Type: AWS::ApiGateway::Stage Properties: DeploymentId: Ref: ServerlessRestApiDeployment RestApiId: Ref: ServerlessRestApi StageName: Prod ListTable: Type: AWS::DynamoDB::Table Properties: ProvisionedThroughput: WriteCapacityUnits: 5 ReadCapacityUnits: 5 AttributeDefinitions: - AttributeName: id AttributeType: S KeySchema: - KeyType: HASH AttributeName: id GetHtmlFunction: Type: AWS::Lambda::Function Properties: Handler: index.gethtml Code: S3Bucket: flourish-demo-bucket S3Key: todo_list.zip Role: Fn::GetAtt: - GetHtmlFunctionRole - Arn Runtime: nodejs4.3 GetHtmlFunctionRole: Type: AWS::IAM::Role Properties: ManagedPolicyArns: - arn:aws:iam::aws:policy/AmazonDynamoDBReadOnlyAccess - arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole AssumeRolePolicyDocument: Version: '2012-10-17' Statement: - Action: - sts:AssumeRole Effect: Allow Principal: Service: - lambda.amazonaws.com ServerlessRestApiDeployment: Type: AWS::ApiGateway::Deployment Properties: RestApiId: Ref: ServerlessRestApi Description: 'RestApi deployment id: 127e3fb91142ab1ddc5f5446adb094442581a90d' StageName: Stage GetHtmlFunctionGetHtmlPermissionTest: Type: AWS::Lambda::Permission Properties: Action: lambda:invokeFunction Principal: apigateway.amazonaws.com FunctionName: Ref: GetHtmlFunction SourceArn: Fn::Sub: arn:aws:execute-api:${AWS::Region}:${AWS::AccountId}:${ServerlessRestApi}/*/ANY/* ServerlessRestApi: Type: AWS::ApiGateway::RestApi Properties: Body: info: version: '1.0' title: Ref: AWS::StackName paths: "/{proxy+}": x-amazon-apigateway-any-method: x-amazon-apigateway-integration: httpMethod: ANY type: aws_proxy uri: Fn::Sub: arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03- 31/functions/${GetHtmlFunction.Arn}/invocations responses: {} swagger: '2.0' CloudFormation template
10. SAM Template Tells AWS CloudFormation this is a SAM template it needs to transform Creates a Lambda function, an API Gateway resource/method and all mapping and permissions necessary AWSTemplateFormatVersion: '2010-09-09’ Transform: AWS::Serverless-2016-10-31 Resources: GetHtmlFunction: Type: AWS::Serverless::Function Properties: CodeUri: s3://sam-demo-bucket/todo_list.zip Handler: index.gethtml Runtime: nodejs4.3 Policies: AmazonDynamoDBReadOnlyAccess Events: GetHtml: Type: Api Properties: Path: /{proxy+} Method: ANY
11. github.com/awslabs/aws-sam-cli AWS SAM CLI CLI tool for local testing of serverless apps Response object and function logs available on your local machine Uses open-source Docker-Lambda images to mimic Lambda’s execution environment (timeout, memory limits, runtimes)
12. AWS Lambda Runtimes
13. 2015 Node.js 0.10 Python 2.7 Java 2016 Node.js 4.3 .NET 2017 Node.js 6.10 Python 3.6 2018 Node.js 8.10 Python 3.7 .NET 2.0 & 2.1 PowerShell Go & Ruby 2019 Node.js 10 Lambda runtimes history
14. How do we port a web app to AWS Lambda?
15. The easy way, cheating a bit! $ npm install aws-serverless-express github.com/awslabs/aws-serverless-express
16. The easy way, cheating a bit! (!) $ pip install zappa $ zappa init $ zappa deploy production https://www.zappa.io
17. from flask import Flask app = Flask(__name__) @app.route('/’) def hello_world(): return 'Hello, World!' from chalice import Chalice app = Chalice(__name__) @app.route('/’) def hello_world(): return 'Hello, World!' The easy way, cheating a bit! (! !) $ pip install chalice # code refactor $ chalice deploy https://chalice.readthedocs.io
19. Coding time!
20. github.com/alexcasalboni/express-app-serverless-porting
21. github.com/alexcasalboni/flask-app-serverless-porting
22. awsdeveloperworkshopcollision.splashthat.com
23. Alex Casalboni Technical Evangelist, AWS @alex_casalboni @ 2019, Amazon Web Services, Inc. or its Affiliates. All rights reserved Thank you! is how