Example

Rules

Demonstrates how helix-rules supports several rule styles in one engine. Shows Java rules, DSL rules, SpEL rules, REST rules, YAML-loaded rules, and rule filtering.

Group: Library
Path: examples/library/rules

Source README

Overview

Helix Java application that shows how to use the different rule styles supported by helix-rules.

Run this example from the shared examples build:


./gradlew -p examples runExample -Pexample=library/rules --init-script "$(pwd)/helix.init.gradle"

What It Shows

authoring a Java rule by extending JavaRule
authoring a DSL-style Java rule by extending DSLRule
evaluating a Spring Expression Language rule with SpelRule
invoking an external decision endpoint with RestRule
loading Java and SpEL rules from YAML with YamlRulesFactory
filtering loaded rules with RuleFilters

Example Output

Helix rules example
java.rule=manual-review
dsl.rule=partner-west-queue
spel.rule=expedite
rest.rule=external-risk-escalate
yaml.java.rule=broker-channel
yaml.spel.rule=broker-priority
yaml.filtered.rules=yaml-priority-spel

Development

Building the Application

Run the following command to build the application:


./gradlew clean build

Testing the Application

Run the following command to run the application tests:


./gradlew test
./gradlew integration

Running the Example

Run the application and inspect the rule results:

The example starts a tiny local HTTP server for the REST rule, so it does not require any external service to be running.


./gradlew run