zoukankan      html  css  js  c++  java
  • [VueJS + Typescript] Decouple Dependencies Using IoC Containers in Vue with TypeScript and InversifyJS

    Using Object Oriented Programming, OOP, style allows us to apply Inversion of Control, IoC, and more patterns. An IoC container helps decoupling dependencies by using a class constructor or properties to identify and inject its dependencies. This lesson will show you how can you create and use an IoC container to decouple an http client and users service dependencies in a Vue component with TypeScript and InversifyJS.

    When you are using Class, you also need to mantain the singleton of Class. Use can use similiar approach as Angular in VueJS as well.

    Install:

    npm i --save inversify reflect-metadata inversify-inject-decorators

    Modify tsconfig.json:

    {
      "compilerOptions": {
        "lib": [
          "dom",
          "es5",
          "es2015"
        ],
        "module": "es2015",
        "moduleResolution": "node",
        "target": "es5",
        "sourceMap": true,
        "emitDecoratorMetadata": true,
        "experimentalDecorators": true,
        "allowSyntheticDefaultImports": true
      }
    }

    main.ts:

    import "reflect-metadata"
    import "core-js/es6/map"
    import "core-js/es6/symbol"
    
    import Vue from 'vue'
    import App from './App.vue'
    
    Vue.config.productionTip = false
    
    /* eslint-disable no-new */
    new Vue({
      el: '#app',
      template: '<App/>',
      components: { App }
    })

    Tip: If you want to create unqiue String, you can use Symbol('UserService'), it is useful tool.

    Create a container.ts, which contains all the singleton services:

    import {Container} from 'inversify';
    import {UsersService} from './user-service';
    import {HttpClient} from './http-client';
    import {TYPES} from './types';
    import getDecorators from 'inversify-inject-decorators';
    
    const container = new Container();
    
    container.bind<UserService>(TYPES.UsersService).to(UsersService);
    container.bind<HttpClient>(TYPES.HttpClient).to(HttpClient);
    
    // Lazy inject is good for props
    const {lazyInject} = getDecorators(container);
    
    export {container, lazyInject}

    Create types.ts:

    export const TYPES = {
        UsersService: Symbol('UsersService'),
        HttpClient: Symbol('HttpClient')
    }

    http-client.ts:

    From:

    export class HttpClient {
        get(url: string): Promise<any> {
            return fetch(url).then(data => data.json())
        }
    }

    To:

    import {injectable} from 'inversify';
    
    @injectable()
    export class HttpClient {
        get(url: string): Promise<any> {
            return fetch(url).then(data => data.json())
        }
    }

    user-service.ts:

    From:

    export class UsersService {
        private http: HttpClient;
    
        constructor() {
            this.http = new HttpClient()
        }
    
        getUsers(): Promise<any> {
            return this.http.get('https://jsonplaceholder.type');
        }
    }

    To:

    import {inject, injectable} from 'inversify';
    import {TYPES} from './types';
    
    @injectable()
    export class UsersService {
    
        constructor(@inject(TYPES.HttpClient) private http) {
        }
    
        getUsers(): Promise<any> {
            return this.http.get('https://jsonplaceholder.type');
        }
    }

    Then we can use UsersService in App.vue:

    <script lang="ts">
    import Vue from 'vue'
    import Component from 'vue-class-component'
    import { lazyInject } from './container'
    import { TYPES } from './types'
    @Component
    export default class App extends Vue {
      users = []
      @lazyInject(TYPES.UsersService)
      usersService
      created() {
        this.usersService.getUsers()
          .then(data => {
            this.users = data
          })
      }
    }
    </script>
  • 相关阅读:
    我的Android学习路线(二)
    利用python3.x实现小爬虫下载贴吧内图片
    我的Android学习路线(一)
    根网科技面试题
    sql语句的执行顺序
    英文面试常见问题汇总
    关于oracle、sqlserver、mysql查询前N条数据的实现
    LinqToSql(一)
    关于一些概念的问题,命名空间,程序集,解决方案,项目
    索引器
  • 原文地址:https://www.cnblogs.com/Answer1215/p/9545719.html
Copyright © 2011-2022 走看看