astro/.changeset/pink-ligers-share.md

astro
minor

Adds experimental rewriting in Astro with a new rewrite() function and the middleware next() function.

The feature is available via an experimental flag in astro.config.mjs:

export default defineConfig({
  experimental: {
    rewriting: true
  }
})

When enabled, you can use rewrite() to render another page without changing the URL of the browser in Astro pages and endpoints.

---
// src/pages/dashboard.astro
if (!Astro.props.allowed) {
	return Astro.rewrite("/")
}
---

// src/pages/api.js
export function GET(ctx) {
  if (!ctx.locals.allowed) {
    return ctx.rewrite("/")
  }
}

The middleware next() function now accepts a parameter with the same type as the rewrite() function. For example, with next("/"), you can call the next middleware function with a new Request.

// src/middleware.js
export function onRequest(ctx, next) {
  if (!ctx.cookies.get("allowed")) {
    return next("/") // new signature
  }
  return next();
}

NOTE: please read the RFC to understand the current expectations of the new APIs.