Astro Info

Astro                    v4.7.1
Node                     v18.17.1
System                   macOS (x64)
Package Manager          npm
Output                   hybrid
Adapter                  @astrojs/vercel/serverless
Integrations             @astrojs/tailwind
                         @astrojs/react
                         auto-import
                         @astrojs/code-snippets
                         @astrojs/mdx
                         astro:db
                         @astrojs/db/file-url
                         @astrojs/sitemap

If this issue only occurs in one browser, which browser is a problem?

No response

Describe the Bug

At the moment, I am using the hybrid mode of Astro.
I want to redirect requests to my homepage when a certain cookie is part of the request.
When I try to read the cookies from the request to the homepage in middleware, I get back undefined.

import { defineMiddleware } from "astro:middleware";

// `context` and `next` are automatically typed
export const onRequest = defineMiddleware(async (context, next) => {
  const response = await next();
  const featureFlagOverrideCookie = context.cookies.get(
    "vercel-flag-overrides",
  )?.value;
  console.log(featureFlagOverrideCookie); // returns undefined
  if (featureFlagOverrideCookie && context.url.pathname === "/") {
    const decryptedFlags = (await decrypt(featureFlagOverrideCookie)) as {
      newFeature: boolean;
    };
    if (decryptedFlags.newFeature) {
      return context.redirect("/homepage-alternative-feature-flag");
    }
  }
  return response;
});

My homepage is statically rendered.
Once I add export const prerender = true to my homepage, I am able to read the cookies correctly.
I thought it was strange that the behaviour of middleware is dependent on the page you're trying to access?
I would expect to be able to intercept the request to static pages too and read cookies/headers from them.
If this is not possible for technical reason, I couldn't really find this in the documentation, so maybe then it could be made clearer there?

What's the expected result?

Either updated docs on what you can/can't read in middleware, or a fix to be able to read the cookies/headers when requesting a static page.

Link to Minimal Reproducible Example

https://github.com/thomasledoux1/website-thomas-astro/tree/feature-flags-vercel-toolbar

Participation

• I am willing to submit a pull request for this issue.