amazon-web-services - 使用cloudformation模板在dynamodb表中发生任何变化时如何触发函数？

Question

使用cloudformation模板在dynamodb表中发生任何变化时如何触发函数

我用过

“类型”:“AWS::Lambda::函数”，

“类型”:“AWS::DynamoDB::表”，

Answer 1

您必须为 DynamoDB Streams 创建一个 AWS::Lambda::EventSourceMapping 类型资源，它将调用 lambda 函数。

假设您的 cloudformation 模板中有 Lambdafunction 和 dynamodb 表资源，下一步将定义 EventSourceMapping，如下面的代码片段所示:

MyLambdaFunction:
    Type: AWS::Lambda::Function
    Properties:
      Runtime: python3.7
      Timeout: '50'
    ..............  
MyDynamoDBTable:
    Type: AWS::DynamoDB::Table
    Properties:
      AttributeDefinitions:
        - AttributeName: id
          AttributeType: S
      .......................
DynamoDBTableStream:
    Type: AWS::Lambda::EventSourceMapping
    Properties:
      # The maximum number of DB items to send to Lambda
      BatchSize: 1  # It can be changed based on the need
      Enabled: True
      EventSourceArn: !GetAtt MyDynamoDBTable.StreamArn
      FunctionName: !GetAtt MyLambdaFunction.Arn
      # Always start at the tail of the Stream
      StartingPosition: LATEST