遍历模板中的AWS Cloudformation资源阵列

Question

从yml（或json）模板在AWS CloudFormation中创建资源时，是否可以在数组上进行迭代以使模板简短易读。例如，我有一个Appsync项目，在其中必须创建一堆几乎相同的AWS类型“ AWS :: AppSync :: Resolver”的解析器。在我用于Cloud Formation的YML模板中，1这样的资源可能看起来像这样

Resource:
 GraphQlAddPostsResolver:
      Type: "AWS::AppSync::Resolver"
      DependsOn: GraphQlSchema
      Properties:
        ApiId:
          Fn::GetAtt: [GraphQlApi, ApiId]
        TypeName: Mutation #<---
        FieldName: addPost #<----
        DataSourceName:
          Fn::GetAtt: [GraphQlLambdaDataSource, Name]
        RequestMappingTemplate: |
          {
              "version" : "2017-02-28",
              "operation": "Invoke",
              "payload": {
                  "field": "addPost", #<---
                  "context": $util.toJson($context)
              }
          }
        ResponseMappingTemplate: |
          $util.toJson($context.result)

我可能有十几个或更多这些解析器，唯一的区别是我用表示的地方<----。有什么办法可以遍历一组值，比如

- Field: addPost
  Type: Mutation
- Field: allPosts
  Type: Query
- Field: getPost
  Type: Query
## etc...

Answer 1

这在AWS CloudFormation中是不可能的。您可以使用嵌套堆栈解决问题。使用AWS :: CloudFormation :: Stack资源。

  FirstResolver:
    Type: AWS::CloudFormation::Stack
    DependsOn: GraphQlSchema
    Properties:
      TemplateURL: ./app-sync-resolver.yml
      Parameters:
        ApiId: !GetAtt GraphQlApi.ApiId
        DataSourceName: !GetAtt GraphQlLambdaDataSource.Name
        Field: addPost
        Type: Mutation

  SecondResolver:
    Type: AWS::CloudFormation::Stack
    DependsOn: GraphQlSchema
    Properties:
      TemplateURL: ./app-sync-resolver.yml
      Parameters:
        ApiId: !GetAtt GraphQlApi.ApiId
        DataSourceName: !GetAtt GraphQlLambdaDataSource.Name
        Field: allPosts
        Type: Query

app-sync-resolver.yml看起来像这样（未经测试！）

AWSTemplateFormatVersion: 2010-09-09
Parameters:
  ApiId:
    Type: String
  DataSourceName:
    Type: String
  Type:
    Type: String
  Field:
    Type: String
Resource:
 GraphQLResolver:
      Type: AWS::AppSync::Resolver
      Properties:
        ApiId: !Ref ApiId
        TypeName: !Ref Type
        FieldName: !Ref Field
        DataSourceName: !Ref DataSourceName
        RequestMappingTemplate: |
          {
              "version" : "2017-02-28",
              "operation": "Invoke",
              "payload": {
                  "field": "${Field}",
                  "context": $util.toJson($context)
              }
          }
        ResponseMappingTemplate: |
          $util.toJson($context.result)