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.ts
demo.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 SomeClass
export {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.ts
import "reflect-metadata"
import {Container, Service,Token} from "typedi";
export interface Factory {create(): any;
}
// FactoryToken.ts
export 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 array
Container.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