serverless.yaml

service: lambda-function-url-custom-domain
frameworkVersion: '3'

provider:
  name: aws
  runtime: nodejs14.x
  region: ${opt:region, 'eu-west-1'}
  lambdaHashingVersion: '20201221'

custom:
  apiDomain: api.example.com  # change by your custom domain
  hostedZoneName: example.com.  # your domain Route 53 hosted zone name
  certificateNVirginaArn: arn:aws:acm:us-east-1:xxxxxx:certificate/xxxxxxx # change by your certificate ARN (should be in North Virginia region)

functions:
  api:
    handler: lambda.handler
    url: true # needed to expose lambda function url !

resources:
  Resources:
    ApiCloudFrontDistribution:
      Type: AWS::CloudFront::Distribution
      DeletionPolicy: Delete
      Properties:
        DistributionConfig:
          Enabled: true
          PriceClass: PriceClass_100
          HttpVersion: http2
          Comment: Api distribution for ${self:custom.apiDomain}
          Origins:
            - Id: ApiGateway
              DomainName: !Select [2, !Split ["/", !GetAtt ApiLambdaFunctionUrl.FunctionUrl]] # extract function url form your lambda resource
              OriginPath: ''
              CustomOriginConfig:
                HTTPPort: 80
                HTTPSPort: 443
                OriginProtocolPolicy: https-only
                OriginSSLProtocols: [TLSv1, TLSv1.1, TLSv1.2]
          DefaultCacheBehavior:
            TargetOriginId: ApiGateway
            ViewerProtocolPolicy: redirect-to-https
            Compress: true
            DefaultTTL: 0
            AllowedMethods:
              - HEAD
              - DELETE
              - POST
              - GET
              - OPTIONS
              - PUT
              - PATCH
            CachedMethods:
              - HEAD
              - OPTIONS
              - GET
            ForwardedValues:
              QueryString: false
              Headers:
                - Accept
                - x-api-key
                - Authorization
              Cookies:
                Forward: none
          Aliases:
            - ${self:custom.apiDomain}
          ViewerCertificate:
            SslSupportMethod: sni-only
            MinimumProtocolVersion: TLSv1.2_2019
            AcmCertificateArn: ${self:custom.certificateNVirginaArn}
    ApiRecordSetGroup:
      Type: AWS::Route53::RecordSetGroup
      DeletionPolicy: Delete
      DependsOn:
        - ApiCloudFrontDistribution
      Properties:
        HostedZoneName: ${self:custom.hostedZoneName}
        RecordSets:
          - Name: ${self:custom.apiDomain}
            Type: A
            AliasTarget:
              HostedZoneId: Z2FDTNDATAQYW2 # Cloudfront default hosted zone ID
              DNSName: { 'Fn::GetAtt': [ApiCloudFrontDistribution, DomainName] } # set the domain of your cloudfront distribution