🚀 Qwik 可恢复性架构源码解读

Qwik 简介

核心理念：

• 恢复式架构（Resumable Architecture）
• 几乎无 JavaScript 的初始加载
• 精确的按需加载机制
• 序列化组件状态
• 智能的水合作用

核心架构概览

四大核心：Qwik（框架入口）、Server（服务端渲染）、Client（客户端激活）、Component（组件系统）

四大核心概念

Qwik 框架入口

// packages/core/src/core.ts
export interface QwikManifest {
  symbols: SymbolManifest[];
  map: SymbolMapper;
  version: string;
  basePath: string;
  scopedStyles: ScopedStyle[];
  bundles: Record<string, string>;
  prefetchResources: string[];
}

export interface QwikVite {
  manifest?: QwikManifest;
  ssr?: {
    resolve: (path: string) => Promise<string>;
  };
}

Qwik 宿主环境

// packages/core/src/host.ts
export const enum QwikEvent {
  Render = 'qrender',
  Visible = 'qvisible',
  Idle = 'qidle',
  Timeout = 'qtimeout',
  BeforeVisible = 'qbeforevisible',
  AfterVisible = 'qaftervisible',
}

export interface QwikHostElement extends HTMLElement {
  qwik?: {
    localId: string;
    component: string;
    event?: QwikEvent;
    ctx: RenderContext;
  };
}

Qwik 插件系统

// packages/core/src/plugins/index.ts
export interface QwikPlugin {
  name: string;
  enforce?: 'pre' | 'post';
  config?: (userConfig: UserConfig) => QwikConfig;
  transform?: (code: string, id: string, options: TransformOptions) => Promise<TransformResult>;
  resolveId?: (id: string, importer?: string) => Promise<ResolvedId> | null;
  load?: (id: string) => Promise<string> | null;
}

// Vite 插件示例
export const qwikVitePlugin = (): Plugin => {
  let manifest: QwikManifest;
  return {
    name: 'vite-plugin-qwik',
    config() {
      return {
        ssr: {
          noExternal: ['@builder.io/qwik'],
        },
      };
    },
    buildEnd() {
      // 生成 manifest
    },
  };
};

Qwik CLI 工具

// packages/create-qwik/src/index.ts
export const createQwik = async (
  options: CreateQwikOptions
): Promise<CreateQwikResult> => {
  // 1. 创建项目结构
  await fs.copy(templatePath, options.projectDir, {
    globOptions: { dot: true },
  });
  
  // 2. 更新配置文件
  const qwikConfig = {
    ...options.qwikConfig,
    basePath: options.basePath,
  };
  
  // 3. 安装依赖
  await installDeps(options.packageManager, options.projectDir);
  
  // 4. 生成初始代码
  await generateInitialFiles(options, qwikConfig);
  
  return {
    projectDir: options.projectDir,
    packageManager: options.packageManager,
    command: options.packageManager === 'npm' ? 'npm run dev' : 'dev',
  };
};

Qwik 状态管理

// packages/core/src/state/state.ts
export interface QwikStore {
  __brand: 'store';
  readonly mutable: MutableStore;
}

export interface MutableStore {
  get<T>(obj: any, key: string): T;
  set<T>(obj: any, key: string, value: T): void;
  deepWatch: (obj: any, key: string, fn: Function) => void;
  onCleanup: (fn: Function) => void;
}

// Store 创建
export function store<T extends object>(init: () => T): QwikStore {
  const mutable = createMutable();
  const initial = init();
  
  return {
    __brand: 'store',
    mutable,
  };
}

Qwik 错误处理

// packages/core/src/error.ts
export class QwikError extends Error {
  constructor(
    message: string,
    public readonly code: string,
    public readonly info?: any
  ) {
    super(message);
    this.name = 'QwikError';
  }
}

export interface ErrorHandler {
  (err: any, element: Element | undefined): void;
}

export const globalErrorHandler: ErrorHandler = (err, element) => {
  console.error('Qwik Error:', err);
  if (err instanceof QwikError) {
    console.error('Code:', err.code);
    if (err.info) {
      console.error('Info:', err.info);
    }
  }
};

Qwik 开发模式

// packages/dev/src/index.ts
export const devServer = async (options: DevServerOptions) => {
  const server = createServer({
    ...options,
    plugins: [
      qwikVitePlugin(),
      // 开发模式特有插件
      vitePluginDevMode(),
      vitePluginHotReload(),
    ],
  });
  
  return server.listen(options.port || 3300, () => {
    console.log(`Qwik dev server running at http://localhost:${options.port || 3300}`);
  });
};

// 热重载插件
const vitePluginHotReload = (): Plugin => {
  return {
    name: 'vite-plugin-hot-reload',
    handleHotUpdate({ file, modules }) {
      // 模块热更新
      return modules.map((m) => {
        return {
          type: 'update',
          timestamp: Date.now(),
          module,
        };
      });
    },
  };
};

Qwik 生产构建

// packages/build/src/index.ts
export const build = async (options: BuildOptions) => {
  // 1. 构建客户端包
  const clientManifest = await buildClient(options);
  
  // 2. 构建服务端包
  const serverManifest = await buildServer(options);
  
  // 3. 优化资源
  await optimizeAssets(clientManifest);
  
  // 4. 生成最终 manifest
  const manifest = mergeManifests(clientManifest, serverManifest);
  
  // 5. 输出构建结果
  await writeBuildOutput(manifest, options);
  
  return manifest;
};

// 构建优化
async function optimizeAssets(manifest: QwikManifest) {
  // 压缩图片
  // tree shaking
  // 代码分割
  // 资源预加载
}

服务器端渲染

// packages/server/src/index.ts
export const renderDocument = async (
  url: string,
  options: RenderOptions
): Promise<string> => {
  const document = await createDocument(url, options);
  const root = document.getElementById('root');
  
  if (root) {
    // 渲染组件
    await renderRoot(root, options);
    
    // 注入激活脚本
    injectActivationScript(document, options);
    
    return serializeDocument(document);
  }
  
  throw new Error('Root element not found');
};

// 创建文档
async function createDocument(url: string, options: RenderOptions): Promise<Document> {
  const document = new Document();
  const html = options.template || await getTemplate(url);
  
  // 解析模板
  document.documentElement.innerHTML = html;
  return document;
}

客户端激活

// packages/client/src/activate.ts
export const activate = async (): Promise<void> => {
  // 1. 加载 manifest
  const manifest = await loadManifest();
  
  // 2. 初始化事件监听
  setupEventListeners();
  
  // 3. 激活组件
  await activateComponents(manifest);
  
  // 4. 执行生命周期
  runLifecycleHooks();
};

// 组件激活
async function activateComponents(manifest: QwikManifest) {
  const elements = document.querySelectorAll('[q\\:component]');
  
  for (const element of elements) {
    const componentId = element.getAttribute('q:component');
    if (componentId) {
      const component = await loadComponent(componentId, manifest);
      await renderComponent(element, component);
    }
  }
}

组件序列化

// packages/core/src/serialize/serialize.ts
export const serializeState = (obj: any): string => {
  return JSON.stringify(obj, (key, value) => {
    // 处理特殊对象
    if (value instanceof Function) {
      return { __type: 'function', name: value.name };
    }
    if (value instanceof Element) {
      return { __type: 'element', tag: value.tagName };
    }
    return value;
  });
};

export const deserializeState = (str: string): any => {
  return JSON.parse(str, (key, value) => {
    if (value?.__type === 'function') {
      return Function(`return ${value.name}`)();
    }
    return value;
  });
};

QRL 运行时库

// packages/core/src/qrl/qrl.ts
export interface QRL {
  __brand: 'qrl';
  readonly symbol: string;
  readonly fragment: string;
  readonly group: string;
}

export const createQRL = (
  symbol: string,
  fragment: string,
  group: string
): QRL => {
  return {
    __brand: 'qrl',
    symbol,
    fragment,
    group,
  };
};

// QRL 解析器
export const resolveQRL = (qrl: QRL, manifest: QwikManifest): string => {
  const bundle = manifest.bundles[qrl.group];
  return `${manifest.basePath}${bundle}#${qrl.symbol}`;
};

QRL 绑定机制

// 组件属性绑定
const bindProps = (element: Element, props: Record<string, any>) => {
  for (const [key, value] of Object.entries(props)) {
    if (key.startsWith('on:')) {
      // 事件绑定
      const eventType = key.slice(3);
      bindEventHandler(element, eventType, value);
    } else if (key.startsWith('q:')) {
      // Qwik 特有属性
      bindQwikAttribute(element, key, value);
    } else {
      // 普通属性
      setAttribute(element, key, value);
    }
  }
};

// 事件处理函数绑定
function bindEventHandler(
  element: Element,
  eventType: string,
  handler: QRL | Function
) {
  const elementListener = (ev: Event) => {
    if (handler instanceof Function) {
      handler(ev);
    } else {
      // QRL 函数调用
      loadQrl(handler).then(fn => fn(ev));
    }
  };
  
  element.addEventListener(eventType, elementListener);
}

QRL 懒加载策略

// packages/core/src/lazy/lazy.ts
export const lazyLoadQRL = async (qrl: QRL): Promise<Function> => {
  // 1. 检查缓存
  if (qrlCache.has(qrl)) {
    return qrlCache.get(qrl)!;
  }
  
  // 2. 动态导入
  const module = await import(resolveQRL(qrl, getManifest()));
  const fn = module[qrl.symbol];
  
  // 3. 缓存结果
  qrlCache.set(qrl, fn);
  
  return fn;
};

// 预加载策略
export const prefetchQRL = (qrl: QRL): void => {
  // 使用 IntersectionObserver 监听元素
  if ('IntersectionObserver' in window) {
    const observer = new IntersectionObserver((entries) => {
      entries.forEach((entry) => {
        if (entry.isIntersecting) {
          lazyLoadQRL(qrl);
          observer.unobserve(entry.target);
        }
      });
    });
    
    // 监听可交互元素
    const element = document.querySelector(`[q\\:qrl="${qrl.symbol}"]`);
    if (element) {
      observer.observe(element);
    }
  }
};

事件系统

// packages/core/src/event/event.ts
export const qwikEvent = {
  add: (
    el: Element,
    name: string,
    qrl: QRL,
    options?: AddEventListenerOptions
  ) => {
    const listener = createEventListener(qrl);
    el.addEventListener(name, listener, options);
    return () => el.removeEventListener(name, listener);
  },
  
  remove: (el: Element, name: string, qrl: QRL) => {
    // 移除事件监听器
  },
};

// 事件监听器工厂
function createEventListener(qrl: QRL): EventListener {
  return async (event: Event) => {
    const fn = await lazyLoadQRL(qrl);
    fn(event);
  };
}

生命周期钩子

// packages/core/src/hook/hook.ts
export interface LifecycleHooks {
  onMount?: () => void | Promise<void>;
  onUpdate?: () => void | Promise<void>;
  onUnMount?: () => void | Promise<void>;
  onVisible?: () => void | Promise<void>;
}

export const useLifecycle = (): LifecycleHooks => {
  const hooks = useRef<LifecycleHooks>({});
  
  // 挂载钩子
  useEffect(() => {
    if (hooks.current.onMount) {
      hooks.current.onMount();
    }
  }, []);
  
  // 更新钩子
  useEffect(() => {
    if (hooks.current.onUpdate) {
      hooks.current.onUpdate();
    }
  }, []);
  
  return hooks.current;
};

组件懒加载

// packages/core/src/lazy/component.ts
export const lazy = <T extends Component>(
  loader: () => Promise<T>
): ComponentType => {
  let component: T | null = null;
  
  return function LazyComponent(props: any) {
    const [Component, setComponent] = useState<T>(() => null);
    
    useEffect(() => {
      if (!component) {
        loader().then(comp => {
          component = comp;
          setComponent(comp);
        });
      }
    }, []);
    
    if (!Component) {
      return <div>Loading...</div>;
    }
    
    return <Component {...props} />;
  };
};

// 路由级懒加载
export const Route = lazy(() => import('./pages/Home.page.tsx'));

路由系统

// packages/core/src/router/router.ts
export const Router: Component = () => {
  const [route, setRoute] = useLocation();
  
  useEffect(() => {
    const handlePopstate = () => setRoute(window.location.pathname);
    window.addEventListener('popstate', handlePopstate);
    return () => window.removeEventListener('popstate', handlePopstate);
  }, []);
  
  return useRoutes(route);
};

// 路由匹配
function useRoutes(path: string): JSX.Element {
  switch (path) {
    case '/':
      return <Home />;
    case '/about':
      return <About />
    default:
      return <NotFound />;
  }
}

布局系统

// packages/core/src/layout/layout.ts
export const Layout: Component = ({ children }) => {
  return (
    <html>
      <head>
        <title>Qwik App</title>
        <meta charset="UTF-8" />
      </head>
      <body>
        <Header />
        <main>{children}</main>
        <Footer />
      </body>
    </html>
  );
};

export const Header: Component = () => {
  const [isMenuOpen, setIsMenuOpen] = useState(false);
  
  return (
    <header>
      <nav>
        <button onClick={() => setIsMenuOpen(!isMenuOpen)}>
          Menu
        </button>
        {/* 菜单内容 */}
      </nav>
    </header>
  );
};

样式处理

// packages/core/src/style/style.ts
export const useStyles = (css: string): void => {
  useEffect(() => {
    const style = document.createElement('style');
    style.textContent = css;
    document.head.appendChild(style);
    
    return () => {
      document.head.removeChild(style);
    };
  }, [css]);
};

// 组件样式
export const Button: Component = ({ children, className }) => {
  useStyles(`
    .button {
      padding: 8px 16px;
      border: none;
      border-radius: 4px;
      cursor: pointer;
    }
    .button:hover {
      opacity: 0.8;
    }
  `);
  
  return (
    <button className={`button ${className}`}>
      {children}
    </button>
  );
};

状态恢复机制

// packages/core/src/resume/resume.ts
export const useResumeState = <T>(
  key: string,
  defaultValue: T
): [T, (value: T) => void] => {
  const [state, setState] = useState<T>(defaultValue);
  
  useEffect(() => {
    // 从 localStorage 恢复状态
    const saved = localStorage.getItem(key);
    if (saved) {
      setState(JSON.parse(saved));
    }
  }, [key]);
  
  const setResumeState = (value: T) => {
    setState(value);
    localStorage.setItem(key, JSON.stringify(value));
  };
  
  return [state, setResumeState];
};

// 使用示例
const [count, setCount] = useResumeState('counter', 0);

序列化机制

// packages/core/src/serialize/index.ts
export const serialize = (value: any): string => {
  if (value === null || value === undefined) {
    return 'null';
  }
  
  if (typeof value === 'string') {
    return JSON.stringify(value);
  }
  
  if (typeof value === 'number' || typeof value === 'boolean') {
    return value.toString();
  }
  
  if (Array.isArray(value)) {
    return `[${value.map(serialize).join(',')}]`;
  }
  
  if (typeof value === 'object') {
    const entries = Object.entries(value).map(
      ([k, v]) => `"${k}":${serialize(v)}`
    );
    return `{${entries.join(',')}}`;
  }
  
  return 'null';
};

反序列化流程

// packages/core/src/deserialize/deserialize.ts
export const deserialize = (str: string): any => {
  try {
    const parsed = JSON.parse(str);
    
    // 处理特殊类型
    if (typeof parsed === 'object' && parsed !== null) {
      if (parsed.__type === 'date') {
        return new Date(parsed.value);
      }
      if (parsed.__type === 'regexp') {
        return new RegExp(parsed.pattern, parsed.flags);
      }
      if (parsed.__type === 'function') {
        return Function(`return ${parsed.code}`)();
      }
    }
    
    return parsed;
  } catch (error) {
    console.error('Deserialization error:', error);
    return null;
  }
};

// 高级反序列化
export const deepDeserialize = (obj: any): any => {
  if (Array.isArray(obj)) {
    return obj.map(deepDeserialize);
  }
  
  if (typeof obj === 'object' && obj !== null) {
    const result: any = {};
    for (const [key, value] of Object.entries(obj)) {
      result[key] = deepDeserialize(value);
    }
    return result;
  }
  
  return obj;
};

DOM 操作

// packages/core/src/dom/dom.ts
export const createElement = (
  tagName: string,
  attributes?: Record<string, any>,
  children?: Array<Node | string>
): Element => {
  const element = document.createElement(tagName);
  
  // 设置属性
  if (attributes) {
    for (const [key, value] of Object.entries(attributes)) {
      setAttribute(element, key, value);
    }
  }
  
  // 添加子元素
  if (children) {
    for (const child of children) {
      if (typeof child === 'string') {
        element.appendChild(document.createTextNode(child));
      } else {
        element.appendChild(child);
      }
    }
  }
  
  return element;
};

// 设置属性
export const setAttribute = (element: Element, key: string, value: any): void => {
  if (value === null || value === undefined) {
    element.removeAttribute(key);
  } else {
    element.setAttribute(key, value.toString());
  }
};

DOM 事件处理

// packages/core/src/event/dom.ts
export const addEventListener = (
  element: Element,
  type: string,
  listener: EventListenerOrEventListenerObject,
  options?: AddEventListenerOptions
): () => void => {
  element.addEventListener(type, listener, options);
  
  return () => {
    element.removeEventListener(type, listener);
  };
};

// 事件代理
export const delegateEvent = (
  container: Element,
  eventType: string,
  selector: string,
  handler: EventListener
): () => void => {
  const listener = (event: Event) => {
    const target = event.target as Element;
    const element = target.closest(selector);
    
    if (element) {
      handler.call(element, event);
    }
  };
  
  container.addEventListener(eventType, listener);
  return () => container.removeEventListener(eventType, listener);
};

DOM 属性操作

// packages/core/src/dom/props.ts
export const setProperty = (
  element: Element,
  key: string,
  value: any
): void => {
  if (key in element) {
    // 直接设置属性
    (element as any)[key] = value;
  } else {
    // 设置自定义属性
    element.setAttribute(key, value);
  }
};

export const getProperty = (element: Element, key: string): any => {
  if (key in element) {
    return (element as any)[key];
  } else {
    return element.getAttribute(key);
  }
};

// 样式设置
export const setStyle = (
  element: Element,
  key: string,
  value: string
): void => {
  (element.style as any)[key] = value;
};

DOM 插入操作

// packages/core/src/dom/insert.ts
export const appendChild = (
  parent: Element,
  child: Element | string
): void => {
  if (typeof child === 'string') {
    parent.appendChild(document.createTextNode(child));
  } else {
    parent.appendChild(child);
  }
};

export const insertBefore = (
  parent: Element,
  newChild: Element | string,
  referenceChild: Element | null
): void => {
  if (typeof newChild === 'string') {
    const textNode = document.createTextNode(newChild);
    parent.insertBefore(textNode, referenceChild);
  } else {
    parent.insertBefore(newChild, referenceChild);
  }
};

// 批量插入
export const insertMany = (
  parent: Element,
  children: Array<Element | string>,
  referenceChild: Element | null = null
): void => {
  const fragment = document.createDocumentFragment();
  
  children.forEach(child => {
    if (typeof child === 'string') {
      fragment.appendChild(document.createTextNode(child));
    } else {
      fragment.appendChild(child);
    }
  });
  
  parent.insertBefore(fragment, referenceChild);
};

DOM 更新操作

// packages/core/src/dom/update.ts
export const updateChildren = (
  parent: Element,
  newChildren: Array<Element | string>,
  oldChildren: Array<Element | string>
): void => {
  const maxLength = Math.max(newChildren.length, oldChildren.length);
  
  for (let i = 0; i < maxLength; i++) {
    const newChild = newChildren[i];
    const oldChild = oldChildren[i];
    
    if (!oldChild) {
      // 新增
      appendChild(parent, newChild!);
    } else if (!newChild) {
      // 删除
      parent.removeChild(oldChild);
    } else {
      // 更新
      if (newChild !== oldChild) {
        parent.insertBefore(newChild, oldChild);
        parent.removeChild(oldChild);
      }
    }
  }
};

// 属性差异更新
export const updateAttributes = (
  element: Element,
  newAttrs: Record<string, any>,
  oldAttrs: Record<string, any>
): void => {
  // 处理新增和更新的属性
  for (const [key, value] of Object.entries(newAttrs)) {
    setAttribute(element, key, value);
  }
  
  // 处理删除的属性
  for (const key of Object.keys(oldAttrs)) {
    if (!(key in newAttrs)) {
      element.removeAttribute(key);
    }
  }
};

DOM 删除操作

// packages/core/src/dom/remove.ts
export const removeChild = (parent: Element, child: Element): void => {
  parent.removeChild(child);
};

export const removeChildren = (parent: Element): void => {
  while (parent.firstChild) {
    parent.removeChild(parent.firstChild);
  }
};

export const detach = (element: Element): void => {
  const parent = element.parentNode;
  if (parent) {
    parent.removeChild(element);
  }
};

// 清理事件监听器
export const cleanupElement = (element: Element): void => {
  // 移除所有事件监听器
  const clone = element.cloneNode(false) as Element;
  element.parentNode?.replaceChild(clone, element);
  
  // 清理数据
  for (const key of Object.keys(element)) {
    if (key.startsWith('data-')) {
      delete (element as any)[key];
    }
  }
};

DOM 批处理优化

// packages/core/src/dom/batch.ts
export const batch = (fn: () => void): void => {
  // 开始批处理
  const batchData = getBatchData();
  batchData.active = true;
  
  try {
    fn();
  } finally {
    // 结束批处理
    batchData.active = false;
    
    // 执行所有待处理的 DOM 操作
    for (const op of batchData.operations) {
      op();
    }
    
    // 清空操作队列
    batchData.operations = [];
  }
};

// 批处理操作队列
const batchData = {
  active: false,
  operations: [] as Array<() => void>,
};

// 延迟 DOM 操作
export const queueDOMUpdate = (fn: () => void): void => {
  if (batchData.active) {
    batchData.operations.push(fn);
  } else {
    requestAnimationFrame(fn);
  }
};

DOM 优化策略

// packages/core/src/dom/optimize.ts
export const virtualize = (element: Element): VirtualElement => {
  // 创建虚拟 DOM
  return {
    tagName: element.tagName.toLowerCase(),
    attributes: getAttributes(element),
    children: Array.from(element.childNodes).map(child => {
      if (child.nodeType === Node.TEXT_NODE) {
        return child.textContent!;
      } else {
        return virtualize(child as Element);
      }
    }),
  };
};

// 虚拟 DOM 渲染
export const renderVirtual = (
  virtual: VirtualElement,
  parent: Element
): void => {
  const element = createElement(virtual.tagName, virtual.attributes);
  
  virtual.children.forEach(child => {
    if (typeof child === 'string') {
      element.appendChild(document.createTextNode(child));
    } else {
      renderVirtual(child, element);
    }
  });
  
  parent.appendChild(element);
};

DOM 缓存机制

// packages/core/src/dom/cache.ts
const elementCache = new WeakMap<Element, CachedElement>();

interface CachedElement {
  props: Record<string, any>;
  children: Array<Element | string>;
  listeners: Map<string, EventListener>;
}

export const cacheElement = (element: Element): void => {
  const cached: CachedElement = {
    props: getProps(element),
    children: Array.from(element.childNodes).map(node => {
      if (node.nodeType === Node.TEXT_NODE) {
        return node.textContent!;
      }
      return node as Element;
    }),
    listeners: getListeners(element),
  };
  
  elementCache.set(element, cached);
};

export const restoreElement = (element: Element): void => {
  const cached = elementCache.get(element);
  if (cached) {
    // 恢复属性和事件
    applyCachedData(element, cached);
  }
};

DOM 水合作用

// packages/core/src/hydration/hydration.ts
export const hydrate = async (element: Element, component: Component): Promise<void> => {
  // 1. 加载组件
  const Component = await loadComponent(component);
  
  // 2. 绑定事件
  bindEvents(element);
  
  // 3. 激活组件
  await Component(element, getProps(element));
};

// 事件绑定
function bindEvents(element: Element): void {
  const eventElements = element.querySelectorAll('[on\\:*]');
  
  eventElements.forEach(target => {
    const events = Array.from(target.attributes)
      .filter(attr => attr.name.startsWith('on:'))
      .map(attr => ({
        type: attr.name.slice(3),
        handler: attr.value,
      }));
    
    events.forEach(({ type, handler }) => {
      target.addEventListener(type, createEventHandler(handler));
    });
  });
}

// 事件处理器创建
function createEventHandler(qrl: string): EventListener {
  return async (event: Event) => {
    const handler = await loadQRL(qrl);
    handler(event);
  };
}

DOM 预加载策略

// packages/core/src/prefetch/prefetch.ts
export const prefetchResources = (urls: string[]): void => {
  urls.forEach(url => {
    // 预加载脚本
    const link = document.createElement('link');
    link.rel = 'preload';
    link.href = url;
    link.as = 'script';
    document.head.appendChild(link);
  });
};

// 组件预加载
export const prefetchComponents = (components: string[]): void => {
  components.forEach(component => {
    const qrl = createQRL(component, '', '');
    prefetchQRL(qrl);
  });
};

// IntersectionObserver 预加载
export const observeViewport = (element: Element, callback: () => void): void => {
  const observer = new IntersectionObserver((entries) => {
    entries.forEach(entry => {
      if (entry.isIntersecting) {
        callback();
        observer.unobserve(entry.target);
      }
    });
  });
  
  observer.observe(element);
};

性能优化策略

// 记忆化组件
export const memo = <P extends object>(
  Component: ComponentType<P>,
  areEqual: (prevProps: P, nextProps: P) => boolean
): ComponentType<P> => {
  return function MemoizedComponent(props: P) {
    const prevPropsRef = useRef<P>();
    
    if (!prevPropsRef.current || !areEqual(prevPropsRef.current, props)) {
      prevPropsRef.current = props;
    }
    
    return <Component {...prevPropsRef.current} />;
  };
};

包大小优化

// packages/core/src/bundle/size.ts
export const optimizeBundle = (bundle: string): string => {
  // 1. 移除未使用代码
  const unusedCode = findUnusedCode(bundle);
  
  // 2. 压缩和混淆
  const compressed = compress(bundle);
  
  // 3. 代码分割
  const chunks = splitIntoChunks(compressed);
  
  // 4. Tree shaking
  const shaken = treeShake(chunks);
  
  return shaken;
};

// 动态导入优化
export const dynamicImport = (path: string): Promise<any> => {
  // 使用 import() 的优化版本
  return import(/* webpackChunkName: "dynamic-[request]" */ path);
};

// 外部依赖优化
export const optimizeExternals = (externals: string[]): string[] => {
  return externals.filter(dep => {
    // 检查是否必须打包
    return isRequired(dep);
  });
};

加载性能优化

// packages/core/src/performance/load.ts
export const measureLoadTime = (): void => {
  const navigationTiming = performance.getEntriesByType('navigation')[0] as PerformanceNavigationTiming;
  
  console.log('FCP:', navigationTiming.responseStart - navigationTiming.fetchStart);
  console.log('LCP:', getLCP());
  console.log('CLS:', getCLS());
};

// 关键资源加载优化
export const optimizeCriticalResources = (): void => {
  // 1. 优化关键渲染路径
  deferNonCriticalScripts();
  
  // 2. 预加载关键资源
  preloadCriticalAssets();
  
  // 3. 优化字体加载
  optimizeFontLoading();
  
  // 4. 延迟加载非关键资源
  lazyLoadNonCriticalAssets();
};

function deferNonCriticalScripts(): void {
  // 延迟执行非关键脚本
  const scripts = document.querySelectorAll('script[data-defer]');
  
  scripts.forEach(script => {
    const newScript = document.createElement('script');
    newScript.textContent = script.textContent;
    script.parentNode?.replaceChild(newScript, script);
  });
}

运行时性能

// packages/core/src/performance/runtime.ts
export const measureRuntime = (): void => {
  const observer = new PerformanceObserver((list) => {
    for (const entry of list.getEntries()) {
      if (entry.duration > 50) {
        console.warn('Long task detected:', entry);
      }
    }
  });
  
  observer.observe({ entryTypes: ['longtask'] });
};

// 内存管理
export const optimizeMemory = (): void => {
  // 1. 及时清理事件监听器
  const eventListeners = new WeakSet<EventListener>();
  
  // 2. 使用对象池
  const objectPool = new Map<string, Array<any>>();
  
  // 3. 避免内存泄漏
  preventMemoryLeaks();
};

function preventMemoryLeaks(): void {
  // 避免闭包引用
  // 避免全局变量
  // 及时清理定时器
  // 避免不必要的对象创建
}

渲染性能优化

// packages/core/src/performance/render.ts
export const optimizeRendering = (): void => {
  // 1. 使用 requestAnimationFrame
  const rafCallbacks = new Set<() => void>();
  
  // 2. 批量渲染
  const batchRender = (callback: () => void): void => {
    rafCallbacks.add(callback);
    
    if (rafCallbacks.size === 1) {
      requestAnimationFrame(() => {
        const callbacks = Array.from(rafCallbacks);
        rafCallbacks.clear();
        
        callbacks.forEach(cb => cb());
      });
    }
  };
  
  // 3. 使用 OffscreenCanvas
  const useOffscreenCanvas = (element: Element): void => {
    const offscreen = element.transferControlToOffscreen();
    // 在离屏画布上渲染
  };
};

// 帧率优化
export const optimizeFrameRate = (): void => {
  let lastTime = performance.now();
  const frameRate = 60; // 目标帧率
  const frameInterval = 1000 / frameRate;
  
  const throttledRender = (callback: () => void): void => {
    const now = performance.now();
    const elapsed = now - lastTime;
    
    if (elapsed > frameInterval) {
      lastTime = now;
      callback();
    }
  };
};

内存优化

// packages/core/src/memory/memory.ts
export class MemoryPool<T> {
  private pool: T[] = [];
  private creator: () => T;
  private resetter: (item: T) => void;
  
  constructor(creator: () => T, resetter: (item: T) => void) {
    this.creator = creator;
    this.resetter = resetter;
  }
  
  acquire(): T {
    return this.pool.pop() || this.creator();
  }
  
  release(item: T): void {
    this.resetter(item);
    this.pool.push(item);
  }
  
  size(): number {
    return this.pool.length;
  }
}

// 对象池使用示例
const elementPool = new MemoryPool<Element>(
  () => document.createElement('div'),
  (element) => {
    element.innerHTML = '';
    element.className = '';
  }
);

// 内存监控
export const monitorMemory = (): void => {
  const memoryInfo = performance.memory;
  
  if (memoryInfo) {
    console.log('Memory usage:', {
      used: memoryInfo.usedJSHeapSize,
      total: memoryInfo.totalJSHeapSize,
      limit: memoryInfo.jsHeapSizeLimit,
    });
  }
};

缓存策略

// packages/core/src/cache/cache.ts
interface CacheEntry<T> {
  value: T;
  timestamp: number;
  ttl?: number;
}

class Cache<T> {
  private cache = new Map<string, CacheEntry<T>>();
  
  set(key: string, value: T, ttl?: number): void {
    this.cache.set(key, {
      value,
      timestamp: Date.now(),
      ttl,
    });
  }
  
  get(key: string): T | null {
    const entry = this.cache.get(key);
    
    if (!entry) {
      return null;
    }
    
    if (entry.ttl && Date.now() - entry.timestamp > entry.ttl) {
      this.cache.delete(key);
      return null;
    }
    
    return entry.value;
  }
  
  has(key: string): boolean {
    return this.get(key) !== null;
  }
  
  delete(key: string): void {
    this.cache.delete(key);
  }
  
  clear(): void {
    this.cache.clear();
  }
}

// 组件缓存
const componentCache = new Cache<Component>();

export const cachedComponent = <P>(
  loader: () => Promise<ComponentType<P>>,
  key?: string
): ComponentType<P> => {
  return function CachedComponent(props: P) {
    const [Component, setComponent] = useState<ComponentType<P>>(() => null);
    
    useEffect(() => {
      const cached = componentCache.get(key || '');
      if (cached) {
        setComponent(cached);
      } else {
        loader().then(Component => {
          componentCache.set(key || '', Component);
          setComponent(Component);
        });
      }
    }, [key]);
    
    if (!Component) {
      return <div>Loading...</div>;
    }
    
    return <Component {...props} />;
  };
};

最佳实践

调试技巧

// 性能调试
export const debugPerformance = (): void => {
  // 启用性能标记
  performance.mark('qwik-start');
  
  // 测量组件渲染时间
  const renderTime = measureRender();
  console.log('Component render time:', renderTime);
  
  // 监控内存使用
  monitorMemory();
  
  performance.mark('qwik-end');
  performance.measure('qwik-total', 'qwik-start', 'qwik-end');
};

// 状态调试
export const debugState = (state: any): void => {
  console.group('State Debug');
  console.log('State:', state);
  console.log('State type:', typeof state);
  console.log('State size:', JSON.stringify(state).length);
  console.groupEnd();
};

// 组件调试
export const debugComponent = (component: Component): void => {
  const start = performance.now();
  
  const result = component();
  
  const end = performance.now();
  console.log(`Component render took ${end - start}ms`);
  
  return result;
};

开发工具

// packages/dev-tools/src/index.ts
export const devTools = {
  // 组件检查器
  inspectComponent: (element: Element) => {
    console.log('Component info:', {
      name: element.getAttribute('data-component'),
      props: getProps(element),
      state: getState(element),
      listeners: getListeners(element),
    });
  },
  
  // 性能分析器
  profilePerformance: () => {
    console.profile('Qwik Performance');
    // ... 性能测量代码
    console.profileEnd();
  },
  
  // 网络监控
  monitorNetwork: () => {
    const originalFetch = window.fetch;
    
    window.fetch = async (...args) => {
      const start = performance.now();
      const result = await originalFetch(...args);
      const end = performance.now();
      
      console.log(`Network request: ${args[0]}`, {
        duration: end - start,
        status: result.status,
      });
      
      return result;
    };
  },
};

// VSCode 插件
export const vscodeExtension = {
  activate: (context: ExtensionContext) => {
    // 注册命令
    const disposable = commands.registerCommand('qwik.inspect', () => {
      // 组件检查逻辑
    });
    
    context.subscriptions.push(disposable);
  },
};

部署策略

// packages/deploy/src/index.ts
export const deploy = async (options: DeployOptions): Promise<void> => {
  const { platform, config } = options;
  
  switch (platform) {
    case 'vercel':
      await deployToVercel(config);
      break;
    case 'netlify':
      await deployToNetlify(config);
      break;
    case 'cloudflare':
      await deployToCloudflare(config);
      break;
    default:
      throw new Error(`Unsupported platform: ${platform}`);
  }
};

// Vercel 部署
async function deployToVercel(config: VercelConfig): Promise<void> {
  const output = await exec('npx vercel', {
    env: {
      ...process.env,
      VERCEL_TOKEN: config.token,
    },
  });
  
  console.log('Vercel deployment:', output);
}

// 部署优化
export const optimizeDeployment = (config: BuildConfig): BuildConfig => {
  return {
    ...config,
    // 优化构建输出
    minify: true,
    treeShake: true,
    splitChunks: true,
    // 启用缓存
    cache: true,
    // 优化图片
    images: {
      formats: ['webp', 'avif'],
      quality: 80,
    },
  };
};

总结

参考资料

• 官方文档: https://qwik.builder.io/
• 源码仓库: https://github.com/QwikDev/qwik
• 设计文档: https://qwik.builder.io/docs/getting-started/design/
• 核心包源码: https://github.com/QwikDev/qwik/tree/main/packages/core
• Qwik 原理: https://qwik.builder.io/docs/advanced/qwik-principles/
• 性能优化: https://qwik.builder.io/docs/getting-started/performance/