template.yml

AWSTemplateFormatVersion: "2010-09-09"
Transform: AWS::Serverless-2016-10-31
Description: A collection of utilities that integrate with Zendesk

Parameters:
  PrxZendeskApiUsername: { Type: String }
  PrxZendeskApiToken: { Type: String, NoEcho: true }
  SlackAccessToken: { Type: String, NoEcho: true }
  SlackChannelId: { Type: String }
  SlackSigningSecret: { Type: String, NoEcho: true }

Resources:
  NodejsSlackSdkLambdaLayer:
    Type: AWS::Serverless::LayerVersion
    DeletionPolicy: Delete
    UpdateReplacePolicy: Delete
    Metadata:
      BuildMethod: makefile
    Properties:
      Description: Slack SDK npm libraries for Node.js
      ContentUri: lib/nodejs-slack-sdk
      CompatibleRuntimes:
        - nodejs22.x

  SuspendedTicketsPollerFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/suspended-tickets-poller
      Description: >-
        Polls Zendesk for new suspended tickets and react when they are found,
        like by sending notifications to Slack.
      Environment:
        Variables:
          ZENDESK_API_USERNAME: !Ref PrxZendeskApiUsername
          ZENDESK_API_TOKEN: !Ref PrxZendeskApiToken
          SLACK_ACCESS_TOKEN: !Ref SlackAccessToken
          SLACK_CHANNEL_ID: !Ref SlackChannelId
          SUSPENDED_TICKET_CACHE_TABLE_NAME: !Ref SuspendedTicketsPollerCache
      Events:
        Poller:
          Properties:
            Description: Runs the Zendesk suspended tickets poller
            Enabled: true
            Schedule: rate(20 minutes)
          Type: Schedule
      Handler: index.handler
      Layers:
        - !Ref NodejsSlackSdkLambdaLayer
      MemorySize: 128
      Policies:
        - Statement:
            - Action:
                - dynamodb:GetItem
                - dynamodb:PutItem
              Effect: Allow
              Resource: !Sub arn:aws:dynamodb:${AWS::Region}:${AWS::AccountId}:table/${SuspendedTicketsPollerCache}
          Version: "2012-10-17"
      Runtime: nodejs22.x
      Tags:
        prx:meta:tagging-version: 2021-04-07
        prx:cloudformation:stack-name: !Ref AWS::StackName
        prx:cloudformation:stack-id: !Ref AWS::StackId
        prx:ops:environment: Production
        prx:dev:application: Zendesk Toolkit
      Timeout: 16
  SuspendedTicketsPollerLogGroup:
    Type: AWS::Logs::LogGroup
    DeletionPolicy: Delete
    UpdateReplacePolicy: Delete
    Properties:
      LogGroupName: !Sub /aws/lambda/${SuspendedTicketsPollerFunction}
      RetentionInDays: 14
      Tags:
        - { Key: prx:meta:tagging-version, Value: "2021-04-07" }
        - { Key: prx:cloudformation:stack-name, Value: !Ref AWS::StackName }
        - { Key: prx:cloudformation:stack-id, Value: !Ref AWS::StackId }
        - { Key: prx:ops:environment, Value: Production }
        - { Key: prx:dev:application, Value: Zendesk Toolkit }
  SuspendedTicketsPollerErrorAlarm:
    Type: AWS::CloudWatch::Alarm
    Properties:
      AlarmName: "MINOR [Zendesk] Suspended Tickets Poller <prod> EXPERIENCING ERRORS"
      AlarmDescription: >-
        The error rate on the Zendesk app suspended tickets poller has
        exceeded 0.
      ComparisonOperator: GreaterThanThreshold
      Dimensions:
        - Name: FunctionName
          Value: !Ref SuspendedTicketsPollerFunction
      EvaluationPeriods: 2
      MetricName: Errors
      Namespace: AWS/Lambda
      Period: 60
      Statistic: Sum
      Tags:
        - { Key: prx:meta:tagging-version, Value: "2021-04-07" }
        - { Key: prx:cloudformation:stack-name, Value: !Ref AWS::StackName }
        - { Key: prx:cloudformation:stack-id, Value: !Ref AWS::StackId }
        - { Key: prx:ops:environment, Value: Production }
        - { Key: prx:dev:application, Value: Zendesk Toolkit }
      Threshold: 0
      TreatMissingData: notBreaching

  SuspendedTicketsPollerCache:
    Type: AWS::DynamoDB::Table
    DeletionPolicy: Delete
    UpdateReplacePolicy: Delete
    Properties:
      AttributeDefinitions:
        - AttributeName: suspension_id
          AttributeType: S
      BillingMode: PAY_PER_REQUEST
      KeySchema:
        - AttributeName: suspension_id
          KeyType: HASH
      SSESpecification:
        SSEEnabled: false
      Tags:
        - { Key: prx:meta:tagging-version, Value: "2021-04-07" }
        - { Key: prx:cloudformation:stack-name, Value: !Ref AWS::StackName }
        - { Key: prx:cloudformation:stack-id, Value: !Ref AWS::StackId }
        - { Key: prx:ops:environment, Value: Production }
        - { Key: prx:dev:application, Value: Zendesk Toolkit }
      TimeToLiveSpecification:
        AttributeName: cache_expiration
        Enabled: true

  SlackInteractivityEndpointFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/slack-interactivity-endpoint
      Description: >-
        Polls Zendesk for new suspended tickets and react when they are found,
        like by sending notifications to Slack.
      Environment:
        Variables:
          ZENDESK_API_USERNAME: !Ref PrxZendeskApiUsername
          ZENDESK_API_TOKEN: !Ref PrxZendeskApiToken
          SLACK_ACCESS_TOKEN: !Ref SlackAccessToken
          SLACK_SIGNING_SECRET: !Ref SlackSigningSecret
      FunctionUrlConfig:
        AuthType: NONE
        InvokeMode: BUFFERED
      Handler: index.handler
      Layers:
        - !Ref NodejsSlackSdkLambdaLayer
      MemorySize: 128
      Runtime: nodejs22.x
      Tags:
        prx:meta:tagging-version: 2021-04-07
        prx:cloudformation:stack-name: !Ref AWS::StackName
        prx:cloudformation:stack-id: !Ref AWS::StackId
        prx:ops:environment: Production
        prx:dev:application: Zendesk Toolkit
      Timeout: 16
  SlackInteractivityEndpointLogGroup:
    Type: AWS::Logs::LogGroup
    DeletionPolicy: Delete
    UpdateReplacePolicy: Delete
    Properties:
      LogGroupName: !Sub /aws/lambda/${SlackInteractivityEndpointFunction}
      RetentionInDays: 14
      Tags:
        - { Key: prx:meta:tagging-version, Value: "2021-04-07" }
        - { Key: prx:cloudformation:stack-name, Value: !Ref AWS::StackName }
        - { Key: prx:cloudformation:stack-id, Value: !Ref AWS::StackId }
        - { Key: prx:ops:environment, Value: Production }
        - { Key: prx:dev:application, Value: Zendesk Toolkit }
  SlackInteractivityEndpointErrorAlarm:
    Type: AWS::CloudWatch::Alarm
    Properties:
      AlarmName: "MINOR [Zendesk] Slack Interactivity <prod> EXPERIENCING ERRORS"
      AlarmDescription: >-
        The error rate on the Zendesk app Slack interactivity endpoint has
        exceeded 0.
      ComparisonOperator: GreaterThanThreshold
      Dimensions:
        - Name: FunctionName
          Value: !Ref SlackInteractivityEndpointFunction
      EvaluationPeriods: 2
      MetricName: Errors
      Namespace: AWS/Lambda
      Period: 60
      Statistic: Sum
      Tags:
        - { Key: prx:meta:tagging-version, Value: "2021-04-07" }
        - { Key: prx:cloudformation:stack-name, Value: !Ref AWS::StackName }
        - { Key: prx:cloudformation:stack-id, Value: !Ref AWS::StackId }
        - { Key: prx:ops:environment, Value: Production }
        - { Key: prx:dev:application, Value: Zendesk Toolkit }
      Threshold: 0
      TreatMissingData: notBreaching