Create rules

You can create rules in Amazon Fraud Detector console, using the create-rule command, using the CreateRule API, or using the AWS SDK for Python (Boto3).

Each rule must contain a single expression that captures your business logic. All expressions must evaluate to a Boolean value (true or false) and be less than 4,000 characters in length. If-else type conditions are not supported. All variables used in the expression must be predefined in the evaluated event type. Similarly, all lists used in the expression must be predefined, associated with a varible type, and be populated with entries.

The following example creates a rule high_risk for an existing detector payments_detector. The rule associates an expression and an outcome verify_customer with the rule.

Prerequisites

To follow the steps mentioned below, make sure that you complete the following before you proceed with creating rules:

• Create a detector

• Create an outcome

If you are creating a detector, rule, and outcome for your use case, replace the example detector name, rule name, rule expression and outcome name with the names and expressions relevant to your use case.

Create a new rule in the Amazon Fraud Detector console

1. Open the AWS Management Console and sign in to your account. Navigate to Amazon Fraud Detector.

2. In the left navigation pane, choose Detectors and select the detector you created for your use case, example payments_detector.

3. In the payments_detector page, choose Associated rules tab and then choose Create rule.

4. In the New rule page, enter the following:

   1. In the Name, enter a name for the rule, example high_risk

   2. In the Description - optional, optionally enter a rule description, example, This rule captures events with a high ML model score

   3. In the Expression, enter a rule expression for your use case using the Expression quick reference guide. Example $sample_fraud_detection_model_insightscore >900

   4. In the Outcomes, choose the outcome you created for your use case, example verify_customer. An outcome is the result from a fraud prediction and is returned if the rule matches during an evaluation.

5. Choose Save rule

You created a new rule for your detector. This is the version 1 of the rule which Amazon Fraud Detector automatically makes it available for the detector to use.

Create a rule using the AWS SDK for Python (Boto3)

The following example code uses CreateRule API to create a rule high_risk for an existing detector payments_detector. The example code also adds a rule expression and an outcome verify_customer to the rule.

Prerequisites

To use the example code, make sure that you have complete the following before you proceed with creating rules:

• Create a detector

• Create an outcome

If you are creating a detector, rule, and outcome for your use case, replace the example detector name, rule name, rule expression and outcome name with names and expression relevant to your use case.

import boto3
fraudDetector = boto3.client('frauddetector')

fraudDetector.create_rule(
ruleId = 'high_risk',
detectorId = 'payments_detector',
expression = '$sample_fraud_detection_model_insightscore > 900',
language = 'DETECTORPL',
outcomes = ['verify_customer']
)

You have created the version 1 of the rule which Amazon Fraud Detector automatically makes it available for the detector to use.