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
   

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2. About me
   • Software Engineer & Web Developer
   • Worked in a startup for 4.5 years
   • ServerlessDays Organizer
   • AWS Customer since 2013
   

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3. Agenda
   1. Why serverless computing
   2. Choosing a programming language
   3. Live coding (app migration)
   

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4. Why serverless
   computing
   

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5. No server or container
   management
   Flexible scaling
   No idle capacity
   $
   High availability
   

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6. Event-driven architectures
   Services (anything)
   Event source Serverless Function
   

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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
   

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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
   

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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
   

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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
    

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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)
    

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12. AWS Lambda
    Runtimes
    

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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
    

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14. How do we port a web
    app to AWS Lambda?
    

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15. The easy way, cheating a bit!
    $ npm install aws-serverless-express
    github.com/awslabs/aws-serverless-express
    

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16. The easy way, cheating a bit! (!)
    $ pip install zappa
    $ zappa init
    $ zappa deploy production
    https://www.zappa.io
    

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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
    

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19. Coding time!
    

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20. github.com/alexcasalboni/express-app-serverless-porting
    

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21. github.com/alexcasalboni/flask-app-serverless-porting
    

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22. awsdeveloperworkshopcollision.splashthat.com
    

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23. Alex Casalboni
    Technical Evangelist, AWS
    @alex_casalboni
    @ 2019, Amazon Web Services, Inc. or its Affiliates. All rights reserved
    Thank you!
    is how
    

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