AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: Serverless patterns - SNS to Lambda

Resources:
  # Define the SNS topic
  MySnsTopic:
    Type: AWS::SNS::Topic
    Properties:
      Subscription:
        - Protocol: lambda
          Endpoint: !GetAtt TopicConsumerFunction1.Arn    

  # Provide permission for SNS to invoke the Lambda function
  TopicConsumerFunction1Permission:
    Type: 'AWS::Lambda::Permission'
    Properties:
      Action: 'lambda:InvokeFunction'
      FunctionName: !Ref TopicConsumerFunction1
      Principal: sns.amazonaws.com

  # Define the consumer Lambda function
  TopicConsumerFunction1:
    Type: AWS::Serverless::Function 
    Properties:
      CodeUri: src/
      Handler: app.handler
      Runtime: nodejs12.x
      Timeout: 3
      MemorySize: 128

Outputs:
  TopicConsumerFunction1Name:
    Description: TopicConsumerFunction1 function name
    Value: !Ref TopicConsumerFunction1
  
  SNStopicName:
    Description: SNS topic name
    Value: !GetAtt MySnsTopic.TopicName

  SNStopicARN:
    Description: SNS topic ARN
    Value: !Ref MySnsTopic