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    class-privacy

    1.1.1 • Public • Published

    🔒 Javascript Class-Privacy

    Build Status JavaScript Style Guide Project Status: Active – The project has reached a stable, usable state and is being actively developed. npm bundle size

    Lean dry no-dep srp :cup: package to create instances from classes with defined private members. Keep your classes clean und use this instead to define private properties. Uses proxies to hide information.

    Installation and basic usage

    Install this package via NPM like

    $ npm install class-privacy

    The packages exports only one function, that acts similar to an abstract factory. You can pass in a decide function to define rules (e.g. whitelist) for members. The created factory can be used to create (proxies to) instances that contain only the public members.

    import createFactory from 'class-privacy'
     
    export class Person {
      constructor ({ name, age }) {
        this.name = name
        this.age = age
      }
     
      greet () {
        return `Hello, my name is "${this.name}". I am ${this.age} years old.`
      }
    }
     
    // make all functions public, all other members are private 
    const decide = (key, type) => type === 'function'
     
    // create the factory for private persons 
    const createPrivatePerson = createFactory(Person, { decide })
     
    const anon = createPrivatePerson({ name: 'John Doe', age: 42 })
    anon.name // undefined
    anon.age // undefined
    anon.greet() // `Hello, my name is "John Doe". I am 42 years old.`

    Options

    As shown in the example above, the factory can be created with certain configurations, defined as options:

    decide

    A function that is invoked on every access request (proxy get trap) and receives key, type and ClassDefinition to decide, whether this member should be allowed to be public or kept being private.

    Signature:

    decide: (key, type, ClassDefinition) => Boolean

    Non-boolean return values are evaluated as truthy/falsy. If not passed in options, all members are included by default to preserve the original state.

    revealIsProxy

    If this option is set to true the isProxy property will be added to the proxy in order to allow a classification of the Object as proxy.

    import createFactory from 'class-privacy'
     
    export class Person {
      constructor ({ name, age }) {
        this.name = name
        this.age = age
      }
     
      greet () {
        return `Hello, my name is "${this.name}". I am ${this.age} years old.`
      }
    }
     
    const createPrivatePerson = createFactory(Person, { revealIsProxy: true })
    const anon = createPrivatePerson({ name: 'John Doe', age: 42 })
    anon.isProxy // true

    referenceClass

    If this option is set to true the class property will be added to the proxy in order to allow a classification of the instance as proxy to the given class definition.

    import createFactory from 'class-privacy'
     
    export class Person {
      constructor ({ name, age }) {
        this.name = name
        this.age = age
      }
     
      greet () {
        return `Hello, my name is "${this.name}". I am ${this.age} years old.`
      }
    }
     
    const createPrivatePerson = createFactory(Person, { referenceClass: true })
    const anon = createPrivatePerson({ name: 'John Doe', age: 42 })
    anon.class === Person // true

    Code Quality

    We use standard as opinionated but zero-config linter. You can run lint in two modes:

    lint
    $ npm run lint
    lint with auto fixing
    $ npm run lint:fix

    Run the tests

    We use mocha and chai with a mostly (but not strict) behavioural style for testing. You can run the tests in three different contexts:

    Single run
    $ npm run test
    Watch mode
    $ npm run test:watch
    Coverage
    $ npm run test:coverage

    Documentation

    Documentation is using jsDoc and is available as html or markdown version.

    To build the documentation in development, you need to run

    $ npm run docs

    Build the package

    The package can be build into the dist folder using babel and the respective script:

    $ npm run build

    License

    MIT, see license file

    Install

    npm i class-privacy

    DownloadsWeekly Downloads

    0

    Version

    1.1.1

    License

    MIT

    Unpacked Size

    34 kB

    Total Files

    10

    Last publish

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