前回の投稿【初心者向け】CFnでAPI Gateway＋LambdaなAPI作成をまとめてみた
に引き続きCloudFormationネタです

CFnでDynamoDB stream trigger eventを設定します

環境は

dev% aws --version                                                                            
aws-cli/1.16.180 Python/3.7.3 Darwin/18.2.0 botocore/1.12.170

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

ストリームを設定するlambda

template.yaml

  HogeFunction:
    Type: AWS::Serverless::Function
    Properties:
      Timeout: 10
      CodeUri: xxxxxxxxxx
      Handler: app.lambdaHandler
      Runtime: nodejs10.x
      Role: !GetAtt LambdaRole.Arn
      Events:
        Stream:
          Type: DynamoDB
          Properties:
            Stream: !GetAtt DataTable.StreamArn
            BatchSize: 100
            StartingPosition: LATEST
  LambdaRole:
   Type: AWS::IAM::Role
   Properties:
     AssumeRolePolicyDocument:
       Version: '2012-10-17'
       Statement:
       - Effect: Allow
         Principal:
           Service:
           - lambda.amazonaws.com
         Action:
         - sts:AssumeRole
     Path: "/"
     Policies:
       - PolicyDocument:
         Version: '2012-10-17'
         Statement:
         - Effect: Allow
           Action:
           - dynamodb:DescribeStream
           - dynamodb:GetShardIterator
           - dynamodb:GetRecords
           - dynamodb:ListStreams
           Resource: "*"      
         - Effect:
           Action:
           - logs:CreateLogGroup
           - logs:CreateLogStream
           - logs:PutLogEvents       
           Resource: arn:aws:logs:*:*:*

これでcloudformationコマンドを実行するだけ。素敵