amazon-web-services - 如何在无服务器框架YAML中使用Fn::Join？

Question

我在 Serverless.yaml 文件中有一个策略，如下所述。

    AppSyncDynamoDBPolicy:
      Type: AWS::IAM::ManagedPolicy
      Properties:
        Description: 'Managed policy' 
        Path: /appsync/
        PolicyDocument:
          Version: 2012-10-17
          Statement:
            - Effect: Allow
              Action: 
                - dynamodb:GetItem
                - dynamodb:PutItem
                - dynamodb:DeleteItem
                - dynamodb:UpdateItem
                - dynamodb:Query
                - dynamodb:Scan
                - dynamodb:BatchGetItem
                - dynamodb:BatchWriteItem
              Resource: 
                Fn::Join: 
                  - ""
                  - - Fn::GetAtt: [dslvehicleState, Arn]
                    - "*"

当 sls 部署完成时，它会抛出一个错误，如下所述。

An error occurred: AppSyncDynamoDBPolicy - Syntax errors in policy. (Service: AmazonIdentityManagement; Status Code: 400; Error Code: MalformedPolicyDocument; Request ID: 166ba0b3-cc67-11e8-8f74-3339d857f829).

我在这里缺少什么？

Answer 1

使用 Ref 方法尝试一下:

AppSyncDynamoDBPolicy:
  Type: AWS::IAM::ManagedPolicy
  Properties:
    Description: 'Managed policy' 
    Path: /appsync/
    PolicyDocument:
      Version: 2012-10-17
      Statement:
        - Effect: Allow
          Action: 
            - dynamodb:GetItem
            - dynamodb:PutItem
            - dynamodb:DeleteItem
            - dynamodb:UpdateItem
            - dynamodb:Query
            - dynamodb:Scan
            - dynamodb:BatchGetItem
            - dynamodb:BatchWriteItem
          Resource: 
            Fn::Join: 
              - ""
              - - "Ref": "dslvehicleState"
                - "*"