Builder Pattern

• It enables the creation of an easy to use interface to a complex process.
• By Introducing a step by step workflow, npm packages can be made easy to understand and consume

// Course.js
class Course {
  constructor(name, sales, isFree = false, price, isCampain = false) {
    this.name = name
    this.sales = sales || 0
    this.isFree = isFree
    this.price = price || 0
    this.isCampain = isCampain // Advertising Campaign
  }

  toString() {
    return console.log(JSON.stringify(this))
  }
}
module.exports = Course

// CourseBuilder.js
const Course = require('./course')

class CourseBuilder {
  constructor(name, sales = 0, price = 0) {
    this.name = name
    this.sales = sales
    this.price = price
  }

  makePaid(price) {
    this.isFree = false
    this.price = price
    return this
  }

  makeCampain() {
    this.isCampain = true
    return this
  }

  build() {
    return new Course(this)
  }
}

module.exports = CourseBuilder

//App.js
const CourseBuilder = require('./CourseBuilder')

//const course_1 = new CourseBuilder('Design Patterns 1', 0, true, 149 , true);
//const course_2 = new CourseBuilder('Design Patterns 1', 0,false, 0, false);
const course_1 = new CourseBuilder('Design Patterns 1').makePaid(100).makeCampain().build()
const course_2 = new CourseBuilder('Design Patterns 2').build()

course_1.toString()
course_2.toString()