Injeksi Ketergantungan melalui JavaScript Function Properties

Metode injeksi ketergantungan yang terkenal tetapi tidak terlalu populer. Upaya untuk mengimplementasikan metode ini dalam paket DI npm populer. DI lain.

Beberapa kata tentang OOP dan DI

. . ES js .

. 2006 , — PERL. . OO , , PERL , 1, 2, .

2 , , , . , . . , .

JavaScript, , . , , .

TypeScript , , - ( ). .

, JS , . JQuery UI Widget Factory. , - , . ES6 classes ES5 . ES6 DI.

(dependency injection) . , , . , DI, .

DI . , — . , (/ , , , , ...). / . , “”, - . — ! DI.

DI — .

— , . Javascript . . , .

.

App ,

Storage — ( singleton/service),

Date, ( ).

- . (transient) “new”.

- (singleton) “one”.

class App {

    /** @type { function( int ):IDate } */
    newDate;

    /** @type { function(): IStorage } */
    oneStorage;

    construct( newDate, oneStorage ) {
        this.newDate = newDate;
        this.oneStorage = oneStorage;
    }

    main() {
        const oDate1 = this.newDate( 0 );
        const oDate2 = this.newDate( 1000 );
        const oStorage = this.oneStorage();
        oStorage.insert( oDate1.format() + ' - ' + oDate2.format() );
    }
}

, . (lazy). , ( inversify: to, toSelf, toConstantValue, toDynamicValue, toConstructor, toFactory, toFunction, toAutoFactory, toProvider, toService), DI . , .

DI . DI , , . DI .

dependency injection

, , , . dependency injection. :

1. , . .
2. , / . , , .
3. , . , , , , / IDE.

DI. , DI , .

DI . , . , , DI .

, , , , , . , - , - , . . — “-” )

dependency injection javascript/typescript

, “di” npm. ~1400. . npm dependents.

Gitcompare

Codesandbox

https://github.com/inversify/InversifyJS

, , , . )). , . )

https://github.com/typestack/typedi

, , . , , App Date, . , ?

https://github.com/thlorenz/proxyquire

, . . DI, .

https://github.com/jeffijoe/awilix

, “Symbol(Symbol.toPrimitive)”, , - Proxy, Date . .

https://github.com/aurelia/dependency-injection

. Aurelia.

https://github.com/stampit-org/stampit

. . - .

https://github.com/microsoft/tsyringe

Microsoft, . , .

https://github.com/boblauer/mock-require

proxyquire.

https://github.com/mgechev/injection-js

Angular 4. , , useFactory .

https://github.com/young-steveo/bottlejs

. .instanceFactory, .

https://github.com/jaredhanson/electrolyte

. ES6 .

https://github.com/zhang740/power-di

. React. . - . , .

https://github.com/jpex-js/vue-inject

vue ES6 . . ES6 classes, provide inject DI. .

https://github.com/zazoomauro/node-dependency-injection

YAML/JS/JSON . . php symfony , setParameter, , .

https://github.com/justmoon/constitute

, , DI .

https://github.com/owja/ioc

inversify, . , : , , . , .

https://github.com/kraut-dps/di-box

, .

, , DI , , .

“”, :

class Service {
    work () {
        console.log('work');
    }
}

class App {
    oneService;
    main () {
        this.oneService().work();
    }
}

//  es6 ,   DI
class AppBox {
    Service;
    App;

    _oService;

    newApp () {
        const oApp = new this.App();

        //   
        oApp.oneService = this.oneService.bind(this);

        return oApp;
    }

    oneService () {
        if (!this._oService) {
            this._oService = new this.Service();
        }
        return this._oService;
    }
}

const oBox = new AppBox();
oBox.Service = Service;
oBox.App = App;
const oApp = oBox.newApp();
oApp.main();

Box , , .

(.one()), bind(this), . :

import {Box} from "di-box";

class Service {
    work() {
        console.log( 'work' );
    }
}

class App {
    oneService;
    main() {
        this.oneService().work();
    }
}

class AppBox extends Box {
    App;
    Service;

    newService() {
        return new this.Service();
    }

    oneService() {
        return this.one( this.newService );
    }

    newApp() {
        const oApp = new this.App();
        oApp.oneService = this.oneService;
        return oApp;
    }
}

const oBox = new AppBox();
oBox.Service = Service;
oBox.App = App;
const oApp = oBox.newApp();
oApp.main();

codesandbox

:

const oBox = new AppBox();
//  oBox.Service = Service;
oBox.App = App;
const oApp = oBox.newApp(); //   :  Service is undefined
oApp.main();

...

DI . , , . , .

:

constructor( arg1, arg2, arg3 ) {}

// 

constructor( { arg1key: arg1, arg2key: arg2, arg3key: arg3 } ) {}

, . ?

1. - .
2. .

ES . , - . DI .

. undefined. . .

:

class A {
    _arg1;
    _arg2;

    constructor( arg1, arg2 = null ) {
        this._arg1 = arg1;
        this._arg2 = arg2;
    }
}
const instance = new A( 1, 2 );

// 

class A {
    arg1; //  ,   
    arg2 = null; //    null !== undefined
}
const instance = new A();
instance.arg1 = 1;
instance.arg2 = 2;

dependency injection , . di-box.

typescript constructor( public arg1: type, public arg2: type ) Box:

new AppBox( { bNeedSelfCheck: false, sNeedCheckPrefix: null } );

codesandbox.

Jadi dengan di-box kita mendapat kesempatan untuk menulis dalam gaya OOP, dengan kode tambahan yang minimal, tapi cukup yang mengimplementasikan DI. Di satu sisi, ada prototypal "ajaib" dalam pelaksanaannya, tetapi di sisi lain, itu hanya di tingkat meta, dan komponen sendiri dapat menjadi murni dan tahu apa-apa tentang lingkungan.

Saya dengan senang hati akan membahasnya, mungkin saya melewatkan beberapa perpustakaan lain. Atau mungkin Anda tahu cara terbaik untuk mengimplementasikan contoh saya di beberapa implementasi DI. Tulis di komentar.