工程化与框架系列（35）--前端微服务架构实践

前端微服务架构实践 🏗️

引言

随着前端应用规模的不断扩大，微服务架构在前端领域的应用越来越广泛。本文将深入探讨前端微服务架构的实现方案、最佳实践和相关工具。

微服务架构概述

前端微服务架构主要包括以下方面：

应用拆分：基于业务域的应用拆分策略
独立部署：各个微应用的独立开发、构建和部署
运行时集成：微应用的加载、通信和生命周期管理
共享资源：公共依赖、组件库、工具函数等的共享策略
统一管理：路由、状态、权限等的统一管理方案

微服务架构实现

微前端容器

// 微前端容器类
class MicroFrontendContainer {private static instance: MicroFrontendContainer;private apps: Map<string, MicroApp>;private config: ContainerConfig;private constructor() {this.apps = new Map();this.config = {sandbox: true,prefetch: true,isolation: 'iframe',timeout: 3000};}// 获取单例实例static getInstance(): MicroFrontendContainer {if (!MicroFrontendContainer.instance) {MicroFrontendContainer.instance = new MicroFrontendContainer();}return MicroFrontendContainer.instance;}// 注册微应用registerApp(appConfig: MicroAppConfig): void {const app = new MicroApp(appConfig);this.apps.set(appConfig.name, app);// 预加载配置if (this.config.prefetch) {this.prefetchApp(app);}}// 启动微应用async startApp(name: string): Promise<void> {const app = this.apps.get(name);if (!app) {throw new Error(`App ${name} not found`);}try {// 加载微应用资源await this.loadApp(app);// 创建沙箱环境const sandbox = this.createSandbox(app);// 挂载微应用await this.mountApp(app, sandbox);// 初始化通信this.initCommunication(app);} catch (error) {console.error(`Failed to start app ${name}:`, error);throw error;}}// 停止微应用async stopApp(name: string): Promise<void> {const app = this.apps.get(name);if (!app) {throw new Error(`App ${name} not found`);}try {// 卸载微应用await this.unmountApp(app);// 清理沙箱this.cleanupSandbox(app);// 清理资源this.cleanupResources(app);} catch (error) {console.error(`Failed to stop app ${name}:`, error);throw error;}}// 预加载微应用private async prefetchApp(app: MicroApp): Promise<void> {try {const resources = await this.loadResources(app.config.entry);app.setResources(resources);} catch (error) {console.warn(`Failed to prefetch app ${app.config.name}:`, error);}}// 加载微应用资源private async loadApp(app: MicroApp): Promise<void> {if (app.isLoaded()) {return;}const resources = app.getResources() || await this.loadResources(app.config.entry);await this.injectResources(resources);app.setLoaded(true);}// 加载资源private async loadResources(entry: string): Promise<AppResources> {const response = await fetch(entry);const html = await response.text();return {scripts: this.extractScripts(html),styles: this.extractStyles(html),templates: this.extractTemplates(html)};}// 注入资源private async injectResources(resources: AppResources): Promise<void> {// 注入样式await Promise.all(resources.styles.map(style => this.loadStyle(style)));// 注入脚本await Promise.all(resources.scripts.map(script => this.loadScript(script)));}// 创建沙箱环境private createSandbox(app: MicroApp): Sandbox {if (this.config.isolation === 'iframe') {return new IframeSandbox(app);} else {return new JsSandbox(app);}}// 挂载微应用private async mountApp(app: MicroApp,sandbox: Sandbox): Promise<void> {const mountPoint = document.querySelector(app.config.container);if (!mountPoint) {throw new Error(`Mount point ${app.config.container} not found`);}// 执行生命周期钩子await app.beforeMount();// 在沙箱中执行挂载await sandbox.mount(mountPoint);// 更新应用状态app.setMounted(true);// 执行生命周期钩子await app.afterMount();}// 卸载微应用private async unmountApp(app: MicroApp): Promise<void> {if (!app.isMounted()) {return;}// 执行生命周期钩子await app.beforeUnmount();// 移除DOMconst container = document.querySelector(app.config.container);if (container) {container.innerHTML = '';}// 更新应用状态app.setMounted(false);// 执行生命周期钩子await app.afterUnmount();}// 清理沙箱private cleanupSandbox(app: MicroApp): void {const sandbox = app.getSandbox();if (sandbox) {sandbox.cleanup();}}// 清理资源private cleanupResources(app: MicroApp): void {const resources = app.getResources();if (resources) {// 移除样式resources.styles.forEach(style => {const element = document.querySelector(`link[href="${style}"]`);element?.remove();});// 移除脚本resources.scripts.forEach(script => {const element = document.querySelector(`script[src="${script}"]`);element?.remove();});}}// 初始化应用间通信private initCommunication(app: MicroApp): void {const eventBus = EventBus.getInstance();// 注册应用通信处理器app.setMessageHandler(message => {eventBus.emit(`${app.config.name}:message`, message);});// 监听其他应用消息this.apps.forEach(otherApp => {if (otherApp !== app) {eventBus.on(`${otherApp.config.name}:message`,message => {app.postMessage(message);});}});}
}// 微应用类
class MicroApp {private loaded: boolean = false;private mounted: boolean = false;private resources: AppResources | null = null;private sandbox: Sandbox | null = null;private messageHandler: MessageHandler | null = null;constructor(public config: MicroAppConfig) {}// 生命周期钩子async beforeMount(): Promise<void> {await this.invokeLifecycle('beforeMount');}async afterMount(): Promise<void> {await this.invokeLifecycle('afterMount');}async beforeUnmount(): Promise<void> {await this.invokeLifecycle('beforeUnmount');}async afterUnmount(): Promise<void> {await this.invokeLifecycle('afterUnmount');}// 调用生命周期函数private async invokeLifecycle(name: string): Promise<void> {const lifecycle = (window as any)[`${this.config.name}:${name}`];if (typeof lifecycle === 'function') {await lifecycle();}}// 状态管理isLoaded(): boolean {return this.loaded;}setLoaded(loaded: boolean): void {this.loaded = loaded;}isMounted(): boolean {return this.mounted;}setMounted(mounted: boolean): void {this.mounted = mounted;}// 资源管理getResources(): AppResources | null {return this.resources;}setResources(resources: AppResources): void {this.resources = resources;}// 沙箱管理getSandbox(): Sandbox | null {return this.sandbox;}setSandbox(sandbox: Sandbox): void {this.sandbox = sandbox;}// 消息通信setMessageHandler(handler: MessageHandler): void {this.messageHandler = handler;}postMessage(message: any): void {this.messageHandler?.(message);}
}// 沙箱基类
abstract class Sandbox {constructor(protected app: MicroApp) {}abstract mount(container: Element): Promise<void>;abstract cleanup(): void;
}// iframe沙箱
class IframeSandbox extends Sandbox {private iframe: HTMLIFrameElement | null = null;async mount(container: Element): Promise<void> {this.iframe = document.createElement('iframe');this.iframe.src = 'about:blank';this.iframe.style.width = '100%';this.iframe.style.height = '100%';this.iframe.style.border = 'none';container.appendChild(this.iframe);// 注入资源到iframeawait this.injectResources();}cleanup(): void {this.iframe?.remove();this.iframe = null;}private async injectResources(): Promise<void> {if (!this.iframe) return;const resources = this.app.getResources();if (!resources) return;const doc = this.iframe.contentDocument;if (!doc) return;// 注入样式resources.styles.forEach(style => {const link = doc.createElement('link');link.rel = 'stylesheet';link.href = style;doc.head.appendChild(link);});// 注入脚本for (const script of resources.scripts) {await new Promise((resolve, reject) => {const scriptElement = doc.createElement('script');scriptElement.src = script;scriptElement.onload = resolve;scriptElement.onerror = reject;doc.head.appendChild(scriptElement);});}}
}// JS沙箱
class JsSandbox extends Sandbox {private proxy: Window | null = null;async mount(container: Element): Promise<void> {// 创建代理对象this.proxy = new Proxy(window, {get: (target, property) => {// 处理特殊属性if (this.isProtected(property)) {return target[property as keyof Window];}// 返回沙箱中的值return (this.app as any)[property];},set: (target, property, value) => {// 禁止修改保护属性if (this.isProtected(property)) {return false;}// 设置值到沙箱(this.app as any)[property] = value;return true;}});// 在沙箱环境中执行代码this.executeInSandbox(() => {const resources = this.app.getResources();if (!resources) return;// 执行脚本resources.scripts.forEach(script => {const scriptElement = document.createElement('script');scriptElement.src = script;container.appendChild(scriptElement);});});}cleanup(): void {this.proxy = null;}private executeInSandbox(code: Function): void {if (!this.proxy) return;// 保存原始windowconst originalWindow = window;// 替换为代理对象(window as any) = this.proxy;try {// 执行代码code();} finally {// 恢复原始window(window as any) = originalWindow;}}private isProtected(property: string | symbol): boolean {// 保护的全局属性列表const protectedProps = ['window','document','location','history'];return protectedProps.includes(property.toString());}
}// 事件总线
class EventBus {private static instance: EventBus;private handlers: Map<string, Set<Function>>;private constructor() {this.handlers = new Map();}static getInstance(): EventBus {if (!EventBus.instance) {EventBus.instance = new EventBus();}return EventBus.instance;}on(event: string, handler: Function): void {if (!this.handlers.has(event)) {this.handlers.set(event, new Set());}this.handlers.get(event)?.add(handler);}off(event: string, handler: Function): void {this.handlers.get(event)?.delete(handler);}emit(event: string, data?: any): void {this.handlers.get(event)?.forEach(handler => {handler(data);});}
}// 接口定义
interface ContainerConfig {sandbox: boolean;prefetch: boolean;isolation: 'iframe' | 'js';timeout: number;
}interface MicroAppConfig {name: string;entry: string;container: string;props?: Record<string, any>;
}interface AppResources {scripts: string[];styles: string[];templates: string[];
}type MessageHandler = (message: any) => void;// 使用示例
const container = MicroFrontendContainer.getInstance();// 注册微应用
container.registerApp({name: 'app1',entry: 'http://localhost:3001',container: '#app1'
});container.registerApp({name: 'app2',entry: 'http://localhost:3002',container: '#app2'
});// 启动微应用
await container.startApp('app1');// 停止微应用
await container.stopApp('app1');