AWSTemplateFormatVersion: 2010-09-09
Description: Drupal CloudFront Web Distribution
Parameters:
  OriginDnsName:
    Description: The public load balancer dns name.
    Type: String
  OriginAccessProtocol:
    Description: Protocol to be used by CloudFront to connect to Loadbalancer
    Type: String
    AllowedValues:
    - http-only
    - https-only
    - match-viewer
    Default: http-only
    ConstraintDescription: Choose http-only or https-only or match-viewer
  CloudFrontAlias:
    Description: Alias for the CloudFront distribution. E.g. cdn.mysite.com
    Type: List<String>
    Default: cdn.default
    AllowedPattern: "(?!-)[a-zA-Z0-9-.]*(?<!-)"
    ConstraintDescription: Must be a valid fully-qualified domain name.
  CustomSSLCertificateId:
    Default: ''
    Description: The ARN of the SSL certificate in Certificate Manager
    Type: String
  CloudFrontPriceClass:
    AllowedValues:
    - use-all-edge-locations
    - use-only-us-canada-europe-asia
    - use-only-us-canada-europe
    Default: use-all-edge-locations
    Description: Select the price class associated with the maximum price that you
      want to pay for CloudFront service. If you select a price class other than All,
      some of your users may experience higher latency.
    Type: String
    ConstraintDescription: Select a valid CloudFront Price Class.
Mappings:
  CloudFrontPriceClassMap:
    use-all-edge-locations:
      PriceCode: PriceClass_All
    use-only-us-canada-europe-asia:
      PriceCode: PriceClass_200
    use-only-us-canada-europe:
      PriceCode: PriceClass_100
Conditions:
  DistributionHasAliases:
    Fn::Not:
    - Fn::Equals:
      - Fn::Select:
        - 0
        - !Ref CloudFrontAlias
      - cdn.default
  DistributionHasSSL:
    Fn::Not:
    - Fn::Equals:
      - !Ref CustomSSLCertificateId
      - ''
Resources:
  DrupalCloudfrontDistribution:
    Type: AWS::CloudFront::Distribution
    Properties:
      DistributionConfig:
        Aliases:
          Fn::If:
          - DistributionHasAliases
          - !Ref CloudFrontAlias
          - !Ref AWS::NoValue
        ViewerCertificate:
          AcmCertificateArn:
            Fn::If:
            - DistributionHasSSL
            - !Ref CustomSSLCertificateId
            - !Ref AWS::NoValue
          CloudFrontDefaultCertificate:
            Fn::If:
            - DistributionHasSSL
            - !Ref AWS::NoValue
            - true
          SslSupportMethod:
            Fn::If:
            - DistributionHasSSL
            - sni-only
            - !Ref AWS::NoValue
        Comment:
          !Ref AWS::StackName
        DefaultCacheBehavior:
          AllowedMethods: [HEAD, DELETE, POST, GET, OPTIONS, PUT, PATCH]
          MinTTL: 0
          MaxTTL: 31536000
          DefaultTTL: 86400
          ForwardedValues:
            QueryString: false
          TargetOriginId: alb
          ViewerProtocolPolicy: allow-all
          Compress: false
        Enabled: true
        Origins:
        - Id: alb
          DomainName:
            !Ref OriginDnsName
          CustomOriginConfig:
            OriginProtocolPolicy:
              !Ref OriginAccessProtocol
        PriceClass:
          Fn::FindInMap:
          - CloudFrontPriceClassMap
          - !Ref CloudFrontPriceClass
          - PriceCode
      Tags:
      - Key: Name
        Value: Drupal-Cloudfront-Distribution
Outputs:
  CdnUrl:
    Description: The URL of CloudFront Distribution
    Value:
      Fn::GetAtt:
      - DrupalCloudfrontDistribution
      - DomainName