CloudFormation模板：减少样板代码

Question

我正在尝试构建CF模板，以部署由多个Lambda组成的无服务器系统。就我而言，Lambda资源描述具有很多属性；唯一的区别是文件名和处理函数。

如何在模板中定义类似通用的参数集？

此样板太糟糕了：

  LambdaCreateUser:
    Type: AWS::Lambda::Function
    Properties: 
      Code:
        S3Bucket:
          Ref: BucketForLambdas
        S3Key: create_user.zip
      Handler: create_user.lambda_handler
      Runtime: python3.7
      Role: 
        Fn::GetAtt: [ LambdaRole , "Arn" ]
      Environment:
        Variables: { "EnvTable": !Ref EnvironmentTable, "UsersTable": !Ref UsersTable }
  LambdaDeleteUser:
    Type: AWS::Lambda::Function
    Properties: 
      Code:
        S3Bucket:
          Ref: BucketForLambdas
        S3Key: delete_user.zip 
      Handler: delete_user.lambda_handler  
      Runtime: python3.7   
      Role:
        Fn::GetAtt: [ LambdaRole , "Arn" ]
      Environment:
        Variables: { "EnvTable": !Ref EnvironmentTable, "UsersTable": !Ref UsersTable }

Answer 1

您正在寻找的是AWS SAM，它是CloudFormation之上的一层语法糖。使用AWS SAM的模板的基本表示如下所示：

AWSTemplateFormatVersion: '2010-09-09'
Transform: 'AWS::Serverless-2016-10-31'

Globals:
  Function:
    Runtime: python3.7
    Environment:
      Variables:
        EnvTable: !Ref EnvironmentTable
        UsersTable: !Ref UsersTable

Resources:
  LambdaCreateUser:
    Type: AWS::Serverless::Function
    Properties: 
      Code:
        S3Bucket:
          Ref: BucketForLambdas
        S3Key: create_user.zip
      Handler: create_user.lambda_handler
      Role: !GetAtt LambdaRole.Arn
  LambdaDeleteUser:
    Type: AWS::Serverless::Function
    Properties: 
      Code:
        S3Bucket:
          Ref: BucketForLambdas
        S3Key: delete_user.zip 
      Handler: delete_user.lambda_handler  
      Role: !GetAtt LambdaRole.Arn

但这还不是终点。您可以将代码定义替换为代码甚至内联代码的路径，并使用sam build和sam package来构建和上传工件。您也可以用SAM policy templates替换角色定义，以进一步减少样板代码。