Injector Example

src/domain/ports/IInjector.ts

@@ -0,0 +1,3 @@
+export interface IInjector {
+    inject<T>(name : string) : T;
+}

src/domain/services/MusicCatalogService.ts

@@ -1,12 +1,18 @@
 import { IMusicRepository } from "../../domain/ports/IMusicRepository";
 import { Track } from "../../domain/models/Track";
+import { IInjector } from "../../domain/ports/IInjector";
+
 
 
 export class MusicCatalogService {
     private repository: IMusicRepository;
 
     constructor(repository:IMusicRepository){
-        this.repository= repository;
+        this.repository = repository;
+    }
+
+    static new(injector : IInjector) : MusicCatalogService {
+        return new MusicCatalogService(injector.inject<IMusicRepository>("IMusicRepository"))
     }
 
     get(): Track[] {

src/view/MusicComponent.ts

@@ -4,29 +4,20 @@ import { IMusicRepository } from "../domain/ports/IMusicRepository";
 import { Track } from "../domain/models/Track";
 import { VinylCatalog } from "../adapters/music/VinylCatalog";
 
+import { Wiring } from "../wiring/Wiring";
+
 export class MusicComponent {
     constructor() {
 
-        let container : any = { };
-
-        let register = (name : string, fn : Function) => {
-            container[name] = fn;
-        };
-
-        let inject = (name : string) : any => {
-            if (container[name]) {
-                return container[name]();
-            }
-            throw new Error(`Failed to resolve ${name}`)
-        };
-
         console.log('registering IMusicRepository');
-        register('IMusicRepository', () => new VinylCatalog());
+        Wiring.register('IMusicRepository', () => new VinylCatalog());
 
-        let musicRepository = inject("IMusicRepository") as IMusicRepository;
+        var injector = Wiring.GetInjector();
+        let musicRepository = injector.inject<IMusicRepository>("IMusicRepository");
         console.log('IMusicRepository is', musicRepository);
 
-        let musicCatalogService = new MusicCatalogService(musicRepository);
+        //let musicCatalogService = new MusicCatalogService(injector.inject<IMusicRepository>("IMusicRepository"));
+        let musicCatalogService = MusicCatalogService.new(injector);
 
         let track = new Track(8, "Niels 1st", "Niels Kooiman", 45);
         musicCatalogService.add(track);

src/wiring/Wiring.ts

@@ -0,0 +1,20 @@
+
+import { IInjector } from "../domain/ports/IInjector"
+
+export class Wiring implements IInjector {
+    private static container : any = { };
+    public static register(name : string, fn : Function) : void {
+        Wiring.container[name] = fn;
+    };
+
+    public static GetInjector() : IInjector {
+        return new Wiring();
+    }
+
+    public inject = function<T>(name : string) : T {
+        if (Wiring.container[name]) {
+            return Wiring.container[name]();
+        }
+        throw new Error(`Failed to resolve ${name}`)
+    };
+};