feat: always set session-id cookie in example middleware

example/src/middleware.ts

@@ -1,40 +1,43 @@
 import { NextRequest, NextResponse } from "next/server";
+import { UNLEASH_API_PROXY_DEFINITIONS, UNLEASH_COOKIE_NAME } from "./utils";
 import { addBasePath } from "next/dist/client/add-base-path";
 import { flagsClient, evaluateFlags, randomSessionId } from "@unleash/nextjs";
-import { UNLEASH_API_PROXY_DEFINITIONS, UNLEASH_COOKIE_NAME } from "./utils";
 
 export const config = {
-  runtime: "experimental-edge",
-  matcher: "/ab",
+    runtime: "experimental-edge",
 };
 
-export default async function middleware(req: NextRequest) {
-  const sessionId =
-    req.cookies.get(UNLEASH_COOKIE_NAME)?.value || randomSessionId();
-
-  const context = { sessionId }; // You can extend context with other server-side properties
-
-  // Grab definitions from an endpoint cached on the edge
-  const protocol = req.url.startsWith("https") ? "https://" : "http://";
-  const host = req.headers.get("host");
-  const endpoint = addBasePath(UNLEASH_API_PROXY_DEFINITIONS);
-  const token = process.env.UNLEASH_RELAY_SECRET || "";
-  const definitionsUrl = `${protocol}${host}${endpoint}?token=${token}`;
-
-  // Make a request to the edge-cached endpoint
-  const definitions = await fetch(definitionsUrl).then((res) => res.json());
-
-  // Evaluate based on provided context
-  const evaluated = await evaluateFlags(definitions, context);
-
-  const variant = flagsClient(evaluated.toggles).getVariant("nextjs-example")
-    ?.payload?.value;
-
-  const newUrl = req.nextUrl.clone();
-  // Redirect to variant
-  newUrl.pathname = `/ab/${variant === "a" ? "a" : "b"}`;
-  const res = NextResponse.rewrite(newUrl);
-  res.cookies.set(UNLEASH_COOKIE_NAME, sessionId);
-
-  return res;
+export async function middleware(req: NextRequest) {
+    const sessionId =
+        req.cookies.get(UNLEASH_COOKIE_NAME)?.value || `${Math.floor(Math.random() * 1_000_000_000)}`;
+    let res: NextResponse;
+    if (req.nextUrl.pathname.startsWith('/ab')) {
+        const context = { sessionId }; // You can extend context with other server-side properties
+
+        // Grab definitions from an endpoint cached on the edge
+        const protocol = req.url.startsWith("https") ? "https://" : "http://";
+        const host = req.headers.get("host");
+        const endpoint = addBasePath(UNLEASH_API_PROXY_DEFINITIONS);
+        const token = process.env.UNLEASH_RELAY_SECRET || "";
+        const definitionsUrl = `${protocol}${host}${endpoint}?token=${token}`;
+
+        // Make a request to the edge-cached endpoint
+        const definitions = await fetch(definitionsUrl).then((res) => res.json());
+
+        // Evaluate based on provided context
+        const evaluated = await evaluateFlags(definitions, context);
+        const variant = flagsClient(evaluated.toggles).getVariant("nextjs-example")
+          ?.payload?.value;
+
+        const newUrl = req.nextUrl.clone();
+        // Redirect to variant
+        newUrl.pathname = `/ab/${variant === "a" ? "a" : "b"}`;
+        res = NextResponse.rewrite(newUrl);
+    }
+    else {
+        res = NextResponse.next();
+    }
+    res.cookies.set(UNLEASH_COOKIE_NAME, sessionId);
+    return res; 
 }
+