[sitecore-jss-nextjs]: Unit test has been added and refactored

packages/sitecore-jss-nextjs/src/middleware/redirects-middleware.test.ts

@@ -1430,6 +1430,62 @@ describe('RedirectsMiddleware', () => {
       });
     });
 
+    it('should remove x-middleware-next header and redirect 301', async () => {
+      const siteName = 'foo';
+      const res = NextResponse.redirect('http://localhost:3000/found', {});
+      res.headers.set('x-middleware-next', '1');
+      res.cookies.set('sc_site', siteName);
+      const req = createRequest({
+        nextUrl: {
+          href: 'http://localhost:3000/not-found',
+          pathname: '/not-found',
+          locale: 'en',
+          search: '',
+          origin: 'http://localhost:3000',
+          clone() {
+            return Object.assign({}, req.nextUrl);
+          },
+        },
+      });
+
+      const { middleware, fetchRedirects, siteResolver } = createMiddleware({
+        pattern: 'not-found',
+        target: '/found',
+        redirectType: REDIRECT_TYPE_301,
+        isQueryStringPreserved: true,
+        locale: 'en',
+      });
+
+      const expected = NextResponse.redirect('http://localhost:3000/found', {
+        ...res,
+        status: 301,
+        headers: {},
+      });
+
+      const finalRes = await middleware.getHandler()(req, res);
+
+      validateDebugLog('redirects middleware start: %o', {
+        hostname: 'foo.net',
+        language: 'en',
+        pathname: '/not-found',
+      });
+
+      validateEndMessageDebugLog('redirects middleware end in %dms: %o', {
+        headers: {
+          location: 'http://localhost:3000/found',
+          'set-cookie': 'sc_site=foo; Path=/',
+        },
+        redirected: false,
+        status: 301,
+        url: '',
+      });
+
+      expect(siteResolver.getByHost).not.called.to.equal(true);
+      expect(siteResolver.getByName).to.be.calledWith(siteName);
+      expect(fetchRedirects).to.be.calledWith(siteName);
+      expect(finalRes.status).to.equal(expected.status);
+    });
+
     describe('should redirect to normalized path when nextjs specific "path" query string parameter is provided', () => {
       it('should return 301 redirect', async () => {
         const setCookies = () => {};

packages/sitecore-jss-nextjs/src/middleware/redirects-middleware.ts

@@ -143,38 +143,16 @@ export class RedirectsMiddleware extends MiddlewareBase {
         url.href = prepareNewURL.href;
       }
 
-      const normalizedHeaders = new Headers();
-
-      /**
-       * FIX for Netlify service
-       * Netlify doesn’t handle 301/302 redirects if Next.js sets the header x-middleware-next.
-       */
-      if (res?.headers) {
-        res.headers.forEach((value, key) => {
-          if (key.toLowerCase() !== 'x-middleware-next') {
-            normalizedHeaders.set(key, value);
-          }
-        });
-      }
-
       const redirectUrl = decodeURIComponent(url.href);
 
       /** return Response redirect with http code of redirect type **/
       switch (existsRedirect.redirectType) {
-        case REDIRECT_TYPE_301:
-          return NextResponse.redirect(redirectUrl, {
-            ...res,
-            status: 301,
-            statusText: 'Moved Permanently',
-            headers: normalizedHeaders,
-          });
-        case REDIRECT_TYPE_302:
-          return NextResponse.redirect(redirectUrl, {
-            ...res,
-            status: 302,
-            statusText: 'Found',
-            headers: normalizedHeaders,
-          });
+        case REDIRECT_TYPE_301: {
+          return this.createRedirectResponse(redirectUrl, res, 301, 'Moved Permanently');
+        }
+        case REDIRECT_TYPE_302: {
+          return this.createRedirectResponse(redirectUrl, res, 302, 'Found');
+        }
         case REDIRECT_TYPE_SERVER_TRANSFER: {
           return this.rewrite(redirectUrl, req, res || NextResponse.next());
         }
@@ -281,4 +259,30 @@ export class RedirectsMiddleware extends MiddlewareBase {
 
     return new URL(`${url.pathname}`, url.origin);
   }
+
+  /**
+   * Helper function to create a redirect response and remove the x-middleware-next header.
+   * @param {string} url The URL to redirect to.
+   * @param {Response} res The response object.
+   * @param {number} status The HTTP status code of the redirect.
+   * @param {string} statusText The status text of the redirect.
+   * @returns {NextResponse<unknown>} The redirect response.
+   */
+  private createRedirectResponse(
+    url: string,
+    res: Response | undefined,
+    status: number,
+    statusText: string
+  ): NextResponse {
+    const redirect = NextResponse.redirect(url, {
+      ...(res || {}),
+      status,
+      statusText,
+      headers: res?.headers,
+    });
+    if (res?.headers) {
+      redirect.headers.delete('x-middleware-next');
+    }
+    return redirect;
+  }
 }