template.yaml

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: cfn-bot - Cloudformation update tweet bot

Globals:
  Function:
    Timeout: 60

Parameters:
  TwitterAccessTokenKey:
    Type: String

  TwitterAccessTokenSecret:
    Type: String

  NotificationEmail:
    Type: String
    Default: karl@gutwin.org

  MastodonAccessToken:
    Type: String

  MastodonApiBaseUrl:
    Type: String

Resources:
  DynamoTable:
    Type: AWS::DynamoDB::Table
    Properties:
      AttributeDefinitions:
        - AttributeName: hash
          AttributeType: 'S'
      KeySchema:
        - AttributeName: hash
          KeyType: HASH
      BillingMode: PAY_PER_REQUEST
  
  BotFunction:
    Type: AWS::Serverless::Function 
    Properties:
      CodeUri: cfnbot/build/
      Handler: cfnbot.app.lambda_handler
      Runtime: python3.7
      Policies:
        - Version: "2012-10-17"
          Statement:
            - Effect: Allow
              Action:
                - "dynamodb:GetItem"
                - "dynamodb:PutItem"
              Resource: !GetAtt DynamoTable.Arn
      Environment:
        Variables:
          TABLE_NAME: !Ref DynamoTable
          TWITTER_ACCESS_TOKEN_KEY: !Ref TwitterAccessTokenKey
          TWITTER_ACCESS_TOKEN_SECRET: !Ref TwitterAccessTokenSecret
          MASTODON_ACCESS_TOKEN: !Ref MastodonAccessToken
          MASTODON_API_BASE_URL: !Ref MastodonApiBaseUrl
      Events:
        RunBotPeriodically:
          Type: Schedule
          Properties:
            #Schedule: rate(2 minutes)
            Schedule: rate(1 hour)

  AlarmTopic:
    Type: AWS::SNS::Topic
    Properties:
      Subscription:
        - Protocol: email
          Endpoint: !Ref NotificationEmail

  ErrorAlarm:
    Type: AWS::CloudWatch::Alarm
    Properties:
      AlarmActions:
        - !Ref AlarmTopic
      ComparisonOperator: GreaterThanOrEqualToThreshold
      Dimensions:
        - Name: FunctionName
          Value: !Ref BotFunction
      MetricName: Errors
      Namespace: AWS/Lambda
      EvaluationPeriods: 1
      Period: 3600
      Statistic: Sum
      Threshold: '3'

Outputs:
  TableName:
    Description: Dynamo table name
    Value: !Ref DynamoTable
    
  BotFunctionArn:
    Description: "First Lambda Function ARN"
    Value: !GetAtt BotFunction.Arn