# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
# SPDX-License-Identifier: MIT-0

Comment: Streaming transaction data fraud detection workflow
StartAt: Process batch of transactions
States:
  Process batch of transactions:
    Type: Map
    Iterator:
      StartAt: Store transaction
      States:
        Store transaction:
          Type: Task
          Resource: arn:aws:states:::dynamodb:putItem
          Parameters:
            TableName: "${TransactionsTableName}"
            Item:
              transactionid:
                S.$: $.transaction_id
              transaction_request:
                S.$: States.JsonToString($)
          Next: Get transaction prediction
          ResultPath: null
        Get transaction prediction:
          Type: Task
          Parameters:
            DetectorId: "${FraudDetectorID}"
            Entities:
              - EntityId: unknown
                EntityType: customer
            EventId.$: $.transaction_id
            EventTimestamp.$: $.transaction_timestamp
            EventTypeName: transaction_event
            EventVariables:
              customer_email.$: $.customer_email
              order_price.$: $.order_price
              product_category.$: $.product_category
              ip_address.$: $.ip_address
              card_bin.$: $.card_bin
          Resource: arn:aws:states:::aws-sdk:frauddetector:getEventPrediction
          ResultPath: $.FraudDetectorOutput
          Next: Update transaction with prediction
        Update transaction with prediction:
          Type: Task
          Resource: arn:aws:states:::dynamodb:updateItem
          Parameters:
            TableName: "${TransactionsTableName}"
            Key:
              transactionid:
                S.$: $.transaction_id
            UpdateExpression: SET transaction_fraud_prediction = :prediction
            ExpressionAttributeValues:
              ':prediction':
                S.$: States.JsonToString($.FraudDetectorOutput)
          Next: Is transaction suspicious?
          ResultPath: null
        Is transaction suspicious?:
          Type: Choice
          Choices:
            - Not:
                Variable: $.FraudDetectorOutput.RuleResults[0].Outcomes[0]
                StringMatches: approve
              Next: Publish suspicious transaction for review
          Default: Process transaction
        Publish suspicious transaction for review:
          Type: Task
          Resource: arn:aws:states:::sns:publish
          Parameters:
            TopicArn: "${FraudAlertsTopicArn}"
            Message:
              transaction_id.$: $.transaction_id
              fraud_detection_outcome.$: $.FraudDetectorOutput.RuleResults[0].Outcomes[0]
              fraud_detection_score.$: >-
                $.FraudDetectorOutput.ModelScores[0].Scores.transaction_model_insightscore
          End: true
        Process transaction:
          Type: Pass
          End: true
    End: true