Implementing a Simple Micro‑Application Loader with Qiankun: Code Walkthrough and Sandbox Isolation

In this article we walk through a hands‑on implementation of a micro‑application loader inspired by Qiankun, focusing on how to fetch a remote HTML page, process its resources, and mount it into a host container.

We start by preparing two HTML files: a host page containing a container #container and buttons that call loadApp() and unloadApp() , and a simple micro‑app that includes Bootstrap and a login form.

The core of the loader is the loadMicroApp function:

const loadMicroApp = async (containerSelector, name, url) => {
  // fetch HTML
  const html = await (await fetch(url)).text();

  // parse template, scripts, styles
  const { template, scripts, styles } = processTpl(html);

  // embed external CSS as inline