SVO - Subject Verb Object (Business Rule Engine)

It's a Business Rule Engine for nodejs projects. You just input facts and run it. It's based on the linguistic typology and can be used in many scenarios - even though it's *very specific or broadly

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Prerequisites

You need to install nodejs and npm

• Downloading and installing Node.js and npm

Installing the lib

To add the lib to your project just use npm

npm install --save svo

Done, now lets import to the code, write some facts

//index.js
const SVO = require('./SVO');

const facts = [{
    fact: {
        action: 'register_books',
        label: 'Register books',
        rules: [
            "[subject.profile === 'system_adm']",
            "[object.state === 'NY', subject.profile === 'warehouse_manager']"
        ]
    }
}, {
    fact: {
        action: 'register_users',
        label: 'Register Users',
        rules: ["[subject.profile === 'system_adm']"]
    }
}];

Then we write the function SVO.buildFacts and pass the subject and object of the action (whichever you want try out ). Let`s say we have the following scenario:

Some user (John Doe) wants to register a book. So the request action comes from the endpoint and subject from request session, or token (E.g. JWT), and the body is the actual object.

//index.js
(function testBookRegisteringByWareHouseManager() {
    console.log("\n--------1st scenario--------\n")
    const requestSimulationScene = {
        subject: {
            profile: 'warehouse_manager',
            name: 'John Doe',
            email: '[email protected]'
        },
        action: 'register_books',
        object: {
            ISBN: '123-123123',
            name: 'The big adventures',
            state: 'NY'
        }
    };

    SVO.buildFacts(facts)
        .setAction(requestSimulationScene['action'])
        .setSubjectAndObject(requestSimulationScene.subject, requestSimulationScene.object)
        .then((s, v, o) => {
            console.log(`\n>>> Book "${o.name}" was registered`, s, v, o);
        }
        ).fail((s, v, o) => {
            console.log(`\n>>> User "${s.name}" does not have access. `);
        }
        );

})();

(function testBookRegisteringBySystemAdm() {
    console.log("\n--------2nd scenario--------\n")
    const requestSimulationScene = {
        subject: {
            profile: 'system_adm',
            name: 'Mary Doe',
            email: '[email protected]'
        },
        action: 'register_books',
        object: {
            ISBN: '123-123123',
            name: 'The big adventures',
            state: 'NY'
        }
    };

    SVO.buildFacts(facts)
        .setAction(requestSimulationScene['action'])
        .setSubjectAndObject(requestSimulationScene.subject, requestSimulationScene.object)
        .then((s, v, o) => {
            console.log(`\n>>> Book ${o.name} was registered`, s, v, o);
        }
        ).fail((s, v, o) => {
            console.log(`\n>>> User "${s.name}" does not have access. `);
        }
        );
})();


(function testRegisterUserByWareHouseManager() {
    console.log("\n--------3rd scenario--------\n")
    const requestSimulationScene = {
        subject: {
            profile: 'warehouse_manager',
            name: 'John Doe',
            email: '[email protected]'
        },
        action: 'register_users',
        object: {
            profile: 'warehouse_manager',
            name: 'Ramirez Silva',
            email: '[email protected]'
        }
    };

    SVO.buildFacts(facts)
        .setAction(requestSimulationScene['action'])
        .setSubjectAndObject(requestSimulationScene.subject, requestSimulationScene.object)
        .then((s, v, o) => {
            console.log(`\n>>> User: ${o.name} was registered`, s, v, o);
        }
        ).fail((s, v, o) => {
            console.log(`\n>>> User: "${s.name}" has no access rights to Register: ${o.name} `);
        }
        );
})();

and then run it node index.js or npm start

// output

--------1st scenario--------


>>> Book "The big adventures" was registered { profile: 'warehouse_manager',
  name: 'John Doe',
  email: '[email protected]' } register_books { ISBN: '123-123123', name: 'The big adventures', state: 'NY' }
undefined

--------2nd scenario--------


>>> Book The big adventures was registered { profile: 'system_adm',
  name: 'Mary Doe',
  email: '[email protected]' } register_books { ISBN: '123-123123', name: 'The big adventures', state: 'NY' }

--------3rd scenario--------


>>> User: "John Doe" has no access rights to Register: Ramirez Silva

Built With

• node - The web framework used
• npm - Dependency Management

Contributing (future)

Please read CONTRIBUTING.md for details on our code of conduct, and the process for submitting pull requests to us.

Versioning (future)

We use SemVer for versioning. For the versions available, see the tags on this repository.

Authors

• Eric Andrade -

Contributors (future)

See also the list of contributors who participated in this project.

License (future)

This project is licensed under the MIT License - see the LICENSE.md file for details

Acknowledgments

• Inspiration : linguistic typology