Minirule

Simple, readable business rule language for easy definition and interpretation.

Features

• Readable Syntax: Minirule uses a human-friendly syntax that makes it easy to define business rules. This allows non-technical stakeholders to understand and contribute to the rule definitions.

• Dynamic Business Terms: The library supports dynamic business terms, enabling you to define rules with terms like DISCOUNT, BONUS, and more. This flexibility allows you to adapt to changing business needs without modifying the core logic.

• Validation and Interpretation: Minirule provides built-in validation and interpretation capabilities. You can ensure that your rules are syntactically correct and interpret them to derive actionable insights.

Getting Started

Installation

To use Minirule in your project, install it via npm:

npm install minirule
# or
yarn add minirule

Usage

Here's a quick example of how you can define and interpret a business rule using Minirule:

import { interpreter } from "minirule";

const rule = `
rule "New Customer Welcome"
when
  customer.registrationDate is between "2023-01-01" and "2023-12-31"
  and customer.orderCount < 3
  and order.total > 100
then
  apply 15% discount to order.total
end
`;

try {
  const result = interpreter.interpret(rule);
  console.log("Interpreted Rule:", result);
} catch (error) {
  console.error("Error interpreting rule:", error);
}

Playground

For a hands-on experience, visit our Minirule Playground where you can write, validate, and interpret your business rules in real-time. The playground provides an interactive environment to experiment with Minirule without any setup.

Benefits

• No Programming Required: Minirule is designed for business users. You don't need to be a programmer to define and manage your business rules.

• Collaboration: The readable syntax allows for easy sharing and discussion of rules among team members, even in non-technical channels like Slack.

• Adaptability: Easily adapt to new business requirements by defining new terms and rules without changing the underlying code.

Contributing

We welcome contributions to the Minirule library! If you have ideas for improvements or new features, feel free to open an issue or submit a pull request.

Please read the contributing guide.

Coming Soon

We will add more capability as the following:

rule "Loyal Customer Reward"

# Define reusable conditions
define long_time_customer as
  customer.registration_date < "2020-01-01"
  and customer.total_purchases > 5000

when
  long_time_customer
  and (
    customer.last_purchase not recently (3 months)
    or customer.cart_total > 1000
  )
  and customer.status in ["gold", "platinum"]
  and not customer has used promotion "COMEBACK2023"

then
  apply 20% discount to cart.total
  add 500 points to customer.loyalty_account
  send email "loyal_customer_offer" to customer.email
  mark customer as used promotion "COMEBACK2023"

end

Breakdown:

1. Define Feature:

rule "Loyal Customer Reward"
define long_time_customer as
  customer.registration_date < "2020-01-01"
  and customer.total_purchases > 5000

when
  long_time_customer
  and customer.last_purchase > "2023-01-01"
then
  apply 10% discount to order.total
end

2. Or Logical Operator:

rule "Special Offer"
when
  customer.status is "gold"
  or customer.lifetime_value > 10000
then
  apply 15% discount to order.total
end

3. Not Operator:

rule "New Customer Offer"
when
  not customer.has_previous_purchase
  and order.total > 100
then
  apply 20% discount to order.total
end

4. Recently Time-based Condition:

rule "Re-engagement Offer"
when
  customer.last_purchase not recently (3 months)
  and customer.status is "active"
then
  send email "comeback_offer" to customer.email
end

5. In Operator with Array Literals:

rule "Premium Product Discount"
when
  product.category in ["electronics", "appliances"]
  and customer.status in ["gold", "platinum"]
then
  apply 12% discount to product.price
end

6. Has Used Condition:

rule "First-Time Promotion"
when
  not customer has used promotion "WELCOME2023"
  and order.total > 50
then
  apply 25% discount to order.total
  mark customer as used promotion "WELCOME2023"
end

7. Multiple Actions in Then Clause:

rule "VIP Customer Reward"
when
  customer.status is "vip"
  and order.total > 1000
then
  apply 20% discount to order.total
  add 500 points to customer.loyalty_account
  send email "vip_thank_you" to customer.email
end

8. Nested Conditions with Parentheses:

rule "Complex Seasonal Offer"
when
  (customer.status is "gold" or customer.lifetime_value > 5000)
  and (
    (order.total > 200 and order.item_count > 3)
    or (order.contains_category "seasonal" and order.total > 100)
  )
then
  apply 15% discount to order.total
  add 200 points to customer.loyalty_account
end

These enhanced capabilities will provide more flexibility and power in defining complex business rules.

Task List

1. Implement 'Define' feature

   • Add 'Define' and 'As' keyword tokens
   • Implement 'define' clause in the parser
   • Implement visitor for 'define' clause in the interpreter
   • Add new keyword token to playground editor config

2. Add support for 'Or' logical operator

   • Add 'Or' keyword token
   • Extend parser to support 'Or' in conditions
   • Update interpreter to evaluate 'Or' conditions
   • Add new keyword token to playground editor config

3. Implement 'Not' operator

   • Add 'Not' keyword token
   • Extend 'condition' in parser to support 'not' operator
   • Implement 'not' operator evaluation in interpreter
   • Add new keyword token to playground editor config

4. Add 'Recently' time-based condition

   • Add 'Recently' keyword token
   • Add support for time unit tokens (e.g., 'months', 'days', 'years')
   • Implement 'recently' time-based condition in parser
   • Implement 'recently' time-based condition evaluation in interpreter
   • Add new keyword token to playground editor config

5. Implement 'In' operator with array literals

   • Add 'In' keyword token
   • Implement support for square bracket tokens
   • Extend 'condition' in parser to support 'in' operator with array literals
   • Implement 'in' operator evaluation with array literals in interpreter
   • Add new keyword token to playground editor config

6. Add 'Has Used' condition

   • Add 'Has' and 'Used' keyword tokens
   • Extend 'condition' in parser to support 'has used' syntax
   • Implement 'has used' condition evaluation in interpreter
   • Add new keyword token to playground editor config

7. Enhance 'Then' clause for multiple actions

   • Add 'Add', 'Points', 'Send', 'Email', 'Mark' keyword tokens
   • Extend 'thenClause' in parser to support multiple actions
   • Implement new action executions in interpreter (add points, send email, mark as used)
   • Add new keyword token to playground editor config

8. Support nested conditions with parentheses

   • Implement support for parentheses tokens
   • Extend 'whenClause' in parser to support nested conditions with parentheses
   • Extend condition evaluation in interpreter to support nested conditions
   • Add new keyword token to playground editor config

9. Testing

   • Initiate Unit Testing for minirule-language
   • Initiate Unit Testing for minirule-playground

License

Minirule is open-source software licensed under the MIT License.