如何在无服务器框架 YAML 中使用 Fn::Join？

Question

我在 Serverless.yaml 文件中有一个政策，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 deploy 完成后，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).

我在这里错过了什么？

Answer 1

试试这个，使用 Ref 方法：

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"
                - "*"

Answer 2

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: !GetAtt "dslvehicleState.Arn"

您可以详细了解 Return 值 here。

Answer 3

检查并重试后，我发现字符串应该使用 ''

标记

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]
                - "*"

更换以下设置后顺利运行

Version: '2012-10-17' Action: - 'dynamodb:GetItem' - 'dynamodb:PutItem' - 'dynamodb:DeleteItem' - 'dynamodb:UpdateItem' - 'dynamodb:Query' - 'dynamodb:Scan' - 'dynamodb:BatchGetItem' - 'dynamodb:BatchWriteItem'

如何在无服务器框架 YAML 中使用 Fn::Join？

How to user Fn::Join in serverless framework YAML?

amazon-web-services

amazon-cloudformation

amazon-iam

serverless-framework