title: How restrict public access to S3 Bucket in AWS SAM Template
body: <p>I am currently trying to define an s3 bucket for a cloud formation deployment using the SAM template. Following the documentation I thought I was setting the PublicAccessBlockConfiguration correctly:</p>
  
  <pre><code>(yaml)
      S3Bucket1:
          Type: AWS::S3::Bucket
          Properties:
            BucketName: abl-ar-report-container 
            BucketEncryption: 
              ServerSideEncryptionConfiguration: 
              - ServerSideEncryptionByDefault:
                  SSEAlgorithm: AES256
            PublicAccessBlockConfiguration:
              BlockPublicAcls : true
              BlockPublicPolicy : true
              IgnorePublicAcls : true
              RestrictPublicBuckets : true
  </code></pre>
  
  <p>however when I deploy I get the following message:</p>
  
  <p>Resource with id [S3Bucket1] is invalid. property PublicAccessBlockConfiguration not defined for resource of type AWS::S3::Bucket</p>
  
  <p>I did see some references to template variations on git 
  I am declaring the AWS template as:</p>
  
  <pre><code>AWSTemplateFormatVersion: 2010-09-09
  Description: A template for a Node.js-based application 
  
  Transform: AWS::Serverless-2016-10-31
  </code></pre>
  
  <p>After further digging I think I am mixing CF template syntax with SAM syntax. Can anyone point me to the correct documentation or syntax for these settings?</p>