aws-lambda - 如何将 Step 函数的 Arn 传递给 CloudFormation 堆栈中的另一个函数？

Question

我在 CloudFormation 堆栈中创建了一个步骤函数，部署后我需要从堆栈中的另一个函数调用该函数。我不知道该怎么做，而且我遇到了循环依赖。

基本上，我尝试将环境变量传递给作为步骤函数的 ARN 的函数。

这是 CloudFormation 代码:

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: >
    reports stack

Globals:
    Function:
        Timeout: 120
        MemorySize: 2048
        Runtime: python3.9
        Environment:
            Variables:
                STEP_FUNCTION:  !GetAtt Research.Arn   ### =====> how do i do that ?

Parameters:

    ProjectName:
        Description: Name of the Project
        Type: String
        Default: Project

Resources:

    MyApi:
      Type: AWS::Serverless::Api
      Properties:
        StageName: Prod
        TracingEnabled: true
        Cors: 
          AllowMethods: "'DELETE,GET,HEAD,OPTIONS,POST,PUT'"
          AllowHeaders: "'Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token'"
          AllowOrigin: "'*'"
        

    List:
        DependsOn: VideoResearch
        Type: AWS::Serverless::Function 
        Properties:
            CodeUri: functions/
            Handler: get.get         
            Events:
                List:
                    Type: Api 
                    Properties:
                        RestApiId: !Ref MyApi
                        Path: /reports
                        Method: GET
            Policies:
            (...)


    ################ STEP FUNCTION ################

    Research:
      Type: AWS::Serverless::Function 
      Properties:
        CodeUri: functions/
        Handler: runResearch.research
        Policies:
            (...)

  
    StepFunctionToHandleResearchRole:
      Type: "AWS::IAM::Role"
      Properties:
        AssumeRolePolicyDocument:
          Version: "2012-10-17"
          Statement:
            - Effect: "Allow"
              Principal:
                Service:
                  - !Sub states.${AWS::Region}.amazonaws.com
              Action: "sts:AssumeRole"
        Path: "/"
        Policies:
          (...)


    # 
    StepFunctionToHandleVideosResearch:
      Type: "AWS::StepFunctions::StateMachine"
      Properties:
        DefinitionString: !Sub |
              {
                "StartAt": "Research",
                "States": {
                  "Research": {
                    "Type": "Task",
                    "Resource": "${VideoResearch.Arn}", 
                    "End": true
                  }
                }
              }
        RoleArn: !GetAtt [ StepFunctionToHandleResearchRole, Arn ]


Outputs:

  (...)

  # I also tried to export the arn of the function

在我的函数代码中，我有:

stepFunctionARN = os.environ['STEP_FUNCTION']

Answer 1

@Anthony B. 在评论中发布了答案:问题与我将依赖项添加为全局变量这一事实有关，它创建了一个循环依赖项(API=> 本地函数 <= API 查找函数的 ARN => 不不起作用)。

如果您删除全局变量并添加局部变量，并使用“DependsOn:Research”，则一切正常。

API=>created => 创建第一个函数，获取 Arn => 创建其他函数并提供 ARN