typedi 强大的javascript以及typescript 依赖注入框架
typedi 是typestack团队提供的依赖注入解决方案，对于typescript 我们可以使用注解的开发方式，官方的文档也比较详细
javascript 使用
- 基于函数的服务注入
var Service = require("typedi").Service;var Container = require("typedi").Container;var PostRepository = Service(() => ({ getName() { return "hello from post repository"; }}));var PostManager = Service(() => ({ getId() { return "some post id"; }}));class PostQueryBuilder { build() { return "SUPER * QUERY"; }}var PostController = Service([ PostManager, PostRepository, PostQueryBuilder], (manager, repository, queryBuilder) => { return { id: manager.getId(), name: repository.getName(), query: queryBuilder.build() };});var postController = Container.get(PostController);console.log(postController);- 基于名称的注入
var Container = require("typedi").Container;class BeanFactory { constructor(container){} create() { console.log("BeanFactory") }}class SugarFactor { constructor(container){} create() { console.log("SugarFactory") }}class WaterFactory{ constructor(container){} create() { console.log("WaterFactory") }}class CoffeeMaker { constructor(container) { this.beanFactory = container.get("bean.factory"); this.sugarFactory = container.get("sugar.factory"); this.waterFactory = container.get("water.factory"); } make() { this.beanFactory.create(); this.sugarFactory.create(); this.waterFactory.create(); }}Container.set("bean.factory", new BeanFactory(Container));Container.set("sugar.factory", new SugarFactory(Container));Container.set("water.factory", new WaterFactory(Container));Container.set("coffee.maker", new CoffeeMaker(Container));var coffeeMaker = Container.get("coffee.maker");coffeeMaker.make();typescript 使用
对于typescript 的使用我们可以利用ts提供的强大类型能力,以及注解可以编写强大的功能
- 简单service注解
项目结构
ts└── service ├── SomeClass.ts └── demo.tsdemo.ts
import {Container} from "typedi";import {SomeClass } from "./SomeClass"let someClass = Container.get(SomeClass);someClass.someMethod();SomeClass.ts
import "reflect-metadata";import {Service} from "typedi";@Service()class SomeClass { someMethod() { console.log("call from service") }}export default SomeClassexport { SomeClass}- 基于属性的注入
import "reflect-metadata"import {Container, Inject, Service} from "typedi";@Service()class BeanFactory { create() { console.log("BeanFactory") }}@Service()class SugarFactory { create() { console.log("SugarFactory") }}@Service()class WaterFactory { create() { console.log("WaterFactory") }}@Service()class CoffeeMaker { @Inject() beanFactory: BeanFactory; @Inject() sugarFactory: SugarFactory; @Inject() waterFactory: WaterFactory; make() { this.beanFactory.create(); this.sugarFactory.create(); this.waterFactory.create(); }}let coffeeMaker = Container.get(CoffeeMaker);coffeeMaker.make();- 基于服务名的注入
import "reflect-metadata"import {Container, Service, Inject} from "typedi";interface Factory { create(): void;}@Service("bean.factory")class BeanFactory implements Factory { create() { console.log("BeanFactory") }}@Service("sugar.factory")class SugarFactory implements Factory { create() { console.log("SugarFactory") }}@Service("water.factory")class WaterFactory implements Factory { create() { console.log("WaterFactory") }}@Service("coffee.maker")class CoffeeMaker { beanFactory: Factory; sugarFactory: Factory; @Inject("water.factory") waterFactory: Factory; constructor(@Inject("bean.factory") beanFactory: BeanFactory, @Inject("sugar.factory") sugarFactory: SugarFactory) { this.beanFactory = beanFactory; this.sugarFactory = sugarFactory; } make() { this.beanFactory.create(); this.sugarFactory.create(); this.waterFactory.create(); }}let coffeeMaker = Container.get<CoffeeMaker>("coffee.maker");coffeeMaker.make();- 循环依赖的处理
对于循环依赖我们需要指定类型，如下：
// Car.ts@Service()export class Car { @Inject() engine: Engine;}// Engine.ts@Service()export class Engine { @Inject() car: Car;}应该为:// Car.ts@Service()export class Car { @Inject(type => Engine) engine: Engine;}// Engine.ts@Service()export class Engine { @Inject(type => Car) car: Car;}- 注入继承
// Car.ts@Service()export abstract class Car { @Inject() engine: Engine;}// Engine.ts@Service()export class Bus extends Car { // you can call this.engine in this class}- 服务组
方便组合依赖的服务
// Factory.tsimport "reflect-metadata"import {Container, Service,Token} from "typedi";export interface Factory { create(): any;}// FactoryToken.tsexport const FactoryToken = new Token<Factory>("factories");// BeanFactory.ts@Service({ id: FactoryToken, multiple: true })export class BeanFactory implements Factory { create() { console.log("bean created"); }}// SugarFactory.ts@Service({ id: FactoryToken, multiple: true })export class SugarFactory implements Factory { create() { console.log("sugar created"); }}// WaterFactory.ts@Service({ id: FactoryToken, multiple: true })export class WaterFactory implements Factory { create() { console.log("water created"); }}// app.ts// now you can get all factories in a single arrayContainer.import([ BeanFactory, SugarFactory, WaterFactory,]);const factories = Container.getMany(FactoryToken); // factories is Factory[]factories.forEach(factory => factory.create());说明
typedi 功能还是很强大，是web开发中的一个利器
