index.html

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta http-equiv="X-UA-Compatible" content="IE=edge" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>小程序容器</title>
  <style>
    * {
      margin: 0;
    }

    body {
      min-height: 100vh;
    }
  </style>
</head>

<body>
  <script>
    // 默认打开首页
    if (!location.search) {
      location.href = location.href + "?path=pages/home/index&query=" + encodeURIComponent("a=1");
    }
  </script>
  <!-- 实现双进程间的通信机制 -->
  <script>
    let processChannel = {}; // 进程通道管理
    let processMessageQueue = []; // 进程事件池

    const params = new URLSearchParams(location.search);
    const query = Object.fromEntries(params.entries());

    document.write(`<iframe src="./service.html${location.search}" id="service" style="border: none; width: 0; height: 0;"></iframe>`);
    document.write(`<iframe src="./render.html?${params.get("query")}" id="${query.path}" style="border: none; width: 100%; height: 100%;"></iframe>`);

    function getRenderer(path) {
      const iframe = document.getElementById(path);
      return iframe.contentWindow;
    }

    function getService() {
      const iframe = document.getElementById("service");
      return iframe.contentWindow;
    }

    // 检测是否存在事件队列
    function checkProcessMessage(from, channel) {
      let matchMessage;
      if (from === "service") {
        matchMessage = processMessageQueue.filter((message) => message.from === from && message.path === channel);
      } else {
        matchMessage = processMessageQueue.filter((message) => message.from === from);
      }

      matchMessage.forEach((message) => {
        const { from, ...actionData } = message;
        processChannel[channel].postMessage(actionData);
      });

      processMessageQueue = processMessageQueue.filter((message) => !matchMessage.includes(message));
    }

    window.addEventListener("message", function (event) {
      const message = event.data;
      const { from, action, path } = message;
      if (action === "process_finished") {
        // 进程 ready
        if (from === "service") {
          // 主进程通道 ready
          processChannel["service"] = getService();
          // 确认是否存在来自渲染进程的事件队列
          // 如果有发送到 service
          checkProcessMessage("renderer", "service");
        } else {
          // 页面渲染进程通道 ready
          processChannel[path] = getRenderer(path);
          // 确认是否存在来自主进程的事件队列
          // 如果有且 等于 path 就发送给渲染进程 service
          checkProcessMessage("service", path);
        }
        return;
      }

      if (from === "service") {
        const { from, ...actionData } = message;
        // 主进程来的消息，发送到目标渲染进程
        if (processChannel[path]) {
          processChannel[path].postMessage(actionData);
        } else {
          processMessageQueue.push(message);
        }
      } else {
        const { from, ...actionData } = message;
        // 渲染进程来的消息，发送到逻辑层
        if (processChannel.service) {
          processChannel.service.postMessage(actionData);
        } else {
          processMessageQueue.push(message);
        }
      }
    });
  </script>
</body>

</html>