template.yaml

AWSTemplateFormatVersion: "2010-09-09"
Transform: AWS::Serverless-2016-10-31
Description: >
  html-to-pdf-generator-puppeteer

  SAM Template for html-to-pdf-generator-puppeteer

Globals:
  Function:
    Timeout: 15
    
Parameters:
  CorsOriginDomain:
    Type: String
    Default: https://gsswain.com
  Mode:
    Type: String
    Default: AWS
    AllowedValues:
      - AWS
      - SAM_LOCAL

Resources:
  PDFGeneratorFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: pdf-generator/
      Handler: dist/app.handler
      Runtime: nodejs14.x
      MemorySize: 512
      ReservedConcurrentExecutions: 1 # I don't really want to scale up 
      Layers:
        - !Ref PuppeteerDependencyLayer
      Environment:
        Variables:
          PDF_STORAGE_BUCKET_NAME: !Ref PDFStorageS3Bucket
          ALLOWED_CORS_DOMAIN: !Ref CorsOriginDomain
          MODE: !Ref Mode
      
      Policies:
      - Statement:
        - Sid: S3PutObjectWithTagging
          Effect: Allow
          Action:
          - "s3:PutObject*"
          Resource: !Sub "arn:aws:s3:::${PDFStorageS3Bucket}/*"
      Events:
        GeneratePDF:
          Type: Api
          Properties:
            Path: /generate-pdf
            Method: post
            RestApiId: !Ref PDFGeneratorApi
            Auth:
              ApiKeyRequired: true


  PDFGeneratorApi:
    Type: AWS::Serverless::Api
    Properties:
      Auth:
        UsagePlan:
          CreateUsagePlan: PER_API
          Quota:
            Limit: 500   # Yes, no more than 500 requests per month. I don't want to be going beyond the free tier for my Lambda invocations and S3 api calls. 
            Period: MONTH
          Throttle:
            BurstLimit: 2
            RateLimit: 1
      StageName: Prod
      Cors:
        AllowMethods: "'OPTIONS,POST'"
        AllowHeaders: "'Content-Type, X-Api-Key'"
        AllowOrigin: !Sub "'${CorsOriginDomain}'"


  PuppeteerDependencyLayer:
    Type: AWS::Serverless::LayerVersion
    Properties:
        LayerName: puppeteer-layer
        Description: Dependencies for html-to-pdf-generator-puppeteer [puppeteer]
        ContentUri: dependencies/
        CompatibleRuntimes:
          - nodejs14.x
        LicenseInfo: 'Apache License 2.0'
        RetentionPolicy: Retain
  
  PDFStorageS3Bucket:
    Type: AWS::S3::Bucket
  
  S3BucketConditionalPublicReadAccessPolicy:
    Type: "AWS::S3::BucketPolicy"
    Properties:
      Bucket: !Ref PDFStorageS3Bucket
      PolicyDocument:
        Statement:
          - Action:
              - "s3:GetObject"
            Effect: Allow
            Resource: !Sub "arn:aws:s3:::${PDFStorageS3Bucket}/*"
            Principal: "*"
            Condition:
              StringEquals:
                "s3:ExistingObjectTag/public": "yes" # Public access to only objects with public=yes tags

Outputs:
  PDFGeneratorApi:
    Description: "API Gateway endpoint URL for Prod stage for PDF Generator function"
    Value: !Sub "https://${PDFGeneratorApi}.execute-api.${AWS::Region}.amazonaws.com/Prod/generate-pdf/"
  PDFGeneratorFunction:
    Description: "PDF Generator Lambda Function ARN"
    Value: !GetAtt PDFGeneratorFunction.Arn
  PDFGeneratorFunctionIamRole:
    Description: "Implicit IAM Role created for  PDF Generator function"
    Value: !GetAtt PDFGeneratorFunctionRole.Arn