cfnexample

Resources:
  s3bucket:
    Type: "AWS::S3::Bucket"
    Properties:
      AccessControl: PublicRead
      WebsiteConfiguration:
        ErrorDocument: index.html
        IndexDocument: index.html
  bucketpolicy:
    Type: "AWS::S3::BucketPolicy"
    Properties:
      Bucket: !Ref s3bucket
      PolicyDocument:
        Statement:
          -
            Sid: "ABC123"
            Action:
              - "s3:GetObject"
            Effect: Allow
            Resource: !Join ["", ["arn:aws:s3:::", !Ref s3bucket, "/*"]]
            Principal:
              AWS:
                - "*"