From 1ee5266ce9a3e3bf661429e6bd6f5bddc1536664 Mon Sep 17 00:00:00 2001
From: capJavert <dev@kickass.website>
Date: Mon, 25 Nov 2024 21:48:43 +0100
Subject: [PATCH] feat: override traffic to cf

---
 packages/webapp/middleware.ts | 48 +++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 packages/webapp/middleware.ts

diff --git a/packages/webapp/middleware.ts b/packages/webapp/middleware.ts
new file mode 100644
index 0000000000..45f1d9c1d8
--- /dev/null
+++ b/packages/webapp/middleware.ts
@@ -0,0 +1,48 @@
+import { NextRequest, NextResponse } from 'next/server';
+
+const trafficPercentage = 10;
+
+const cfCookieName = 'cf-override';
+
+const isDev = process.env.NODE_ENV !== 'production';
+
+const middleware = async (req: NextRequest): Promise<NextResponse> => {
+  let cfCookie = req.cookies.get(cfCookieName)?.value;
+
+  const nextResponse = NextResponse.next();
+
+  if (typeof cfCookie === 'undefined') {
+    const shouldOverride = Math.random() < trafficPercentage / 100;
+
+    nextResponse.cookies.set(cfCookieName, shouldOverride ? 'true' : 'false', {
+      path: '/',
+      maxAge: 1 * 60 * 60,
+      secure: !isDev,
+      httpOnly: true,
+    });
+
+    cfCookie = 'true';
+  }
+
+  if (cfCookie === 'true') {
+    const cfUrl = new URL(
+      `${req.nextUrl.pathname}${req.nextUrl.search}`,
+      process.env.CF_OVERRIDE_URL,
+    );
+
+    if (!isDev) {
+      return NextResponse.rewrite(cfUrl, nextResponse);
+    }
+  }
+
+  return nextResponse;
+};
+
+export const config = {
+  matcher: [
+    '/((?!api|_next/static|_next/image|favicon|manifest.json|robots.txt|android-chrome).*)',
+    '/',
+  ],
+};
+
+export { middleware };