Route to local proxy when turbo proxy is running

packages/microfrontends/src/bin/check-proxy.ts

@@ -1,10 +1,11 @@
+import { localProxyIsRunning } from './local-proxy-is-running';
+
 export function displayLocalProxyInfo(port: number): void {
   // TODO(olszewski): this is really icky, but since withMicroFrontends is called by two separate processes
   // we can't rely on some shared state so we instead use env to store state
-  const { MFE_PROXY_MESSAGE_PRINTED, TURBO_TASK_HAS_MFE_PROXY } = process.env;
   if (
-    TURBO_TASK_HAS_MFE_PROXY === 'true' &&
-    MFE_PROXY_MESSAGE_PRINTED !== 'true'
+    localProxyIsRunning() &&
+    process.env.MFE_PROXY_MESSAGE_PRINTED !== 'true'
   ) {
     process.env.MFE_PROXY_MESSAGE_PRINTED = 'true';
     // eslint-disable-next-line no-console

packages/microfrontends/src/bin/local-proxy-is-running.ts

@@ -0,0 +1,3 @@
+export function localProxyIsRunning(): boolean {
+  return process.env.TURBO_TASK_HAS_MFE_PROXY === 'true';
+}

packages/microfrontends/src/next/config/index.ts

@@ -12,14 +12,6 @@ function typedEntries<T extends Record<string, unknown>>(
   return Object.entries(obj) as [keyof T, T[keyof T]][];
 }
 
-function isProduction(opts?: WithMicrofrontendsOptions): boolean {
-  if (opts?.isProduction) {
-    return opts.isProduction();
-  }
-
-  return process.env.VERCEL_ENV === 'production';
-}
-
 /**
  * Automatically configures your Next.js application to work with microfrontends.
  *
@@ -72,7 +64,6 @@ export function withMicrofrontends(
         next,
         microfrontend: microfrontends.config,
         opts: {
-          isProduction: isProduction(opts),
           supportPagesRouter: opts?.supportPagesRouter,
         },
       });

packages/microfrontends/src/next/config/transforms/build-id.test.ts

@@ -23,7 +23,6 @@ describe('withMicrofrontends: buildId', () => {
       app: childApp,
       microfrontend: microfrontends.config,
       opts: {
-        isProduction: true,
         supportPagesRouter: true,
       },
     });
@@ -52,7 +51,6 @@ describe('withMicrofrontends: buildId', () => {
       app: defaultApp,
       microfrontend: microfrontends.config,
       opts: {
-        isProduction: true,
         supportPagesRouter: true,
       },
     });
@@ -69,7 +67,6 @@ describe('withMicrofrontends: buildId', () => {
         app: defaultApp,
         microfrontend: microfrontends.config,
         opts: {
-          isProduction: true,
           supportPagesRouter: true,
         },
       }),
@@ -86,7 +83,6 @@ describe('withMicrofrontends: buildId', () => {
       app: childApp,
       microfrontend: microfrontends.config,
       opts: {
-        isProduction: true,
         supportPagesRouter: true,
       },
     });

packages/microfrontends/src/next/config/transforms/redirects.test.ts

@@ -14,7 +14,7 @@ describe('withMicrofrontends: redirects', () => {
   describe('local proxy running', () => {
     beforeEach(() => {
       process.env = { ...OLD_ENV };
-      process.env.TURBO_TASK_HAS_MFE_PROXY = '1';
+      process.env.TURBO_TASK_HAS_MFE_PROXY = 'true';
     });
 
     it('redirects when enabled non-prod', async () => {
@@ -30,7 +30,6 @@ describe('withMicrofrontends: redirects', () => {
         next: nextConfig,
         app,
         microfrontend: mfConfig,
-        opts: { isProduction: false },
       });
 
       expect(newConfig.redirects).toBeDefined();
@@ -61,7 +60,6 @@ describe('withMicrofrontends: redirects', () => {
         next: nextConfig,
         app,
         microfrontend: mfConfig,
-        opts: { isProduction: false },
       });
 
       expect(newConfig.redirects).toBeDefined();
@@ -101,7 +99,6 @@ describe('withMicrofrontends: redirects', () => {
         next: nextConfig,
         app,
         microfrontend: mfConfig,
-        opts: { isProduction: false },
       });
 
       expect(newConfig.redirects).toBeDefined();
@@ -125,6 +122,7 @@ describe('withMicrofrontends: redirects', () => {
     });
 
     it('no redirects prod', () => {
+      process.env.TURBO_TASK_HAS_MFE_PROXY = undefined;
       const mfConfig = MicrofrontendsServer.fromFile({
         filePath: join(fixtures, 'simple.jsonc'),
       }).config;
@@ -137,7 +135,6 @@ describe('withMicrofrontends: redirects', () => {
         next: nextConfig,
         app,
         microfrontend: mfConfig,
-        opts: { isProduction: true },
       });
 
       expect(newConfig.redirects).toBeUndefined();
@@ -163,7 +160,7 @@ describe('withMicrofrontends: redirects', () => {
     });
 
     it('no redirects if non dev env', () => {
-      process.env.VERCEL_ENV = 'staging';
+      process.env.TURBO_TASK_HAS_MFE_PROXY = undefined;
       const mfConfig = MicrofrontendsServer.fromFile({
         filePath: join(fixtures, 'simple.jsonc'),
       }).config;
@@ -181,8 +178,8 @@ describe('withMicrofrontends: redirects', () => {
       expect(newConfig.redirects).toBeUndefined();
     });
 
-    it('redirects if dev env', async () => {
-      process.env.VERCEL_ENV = 'development';
+    it('redirects if turbo is running mfe proxy', async () => {
+      process.env.TURBO_TASK_HAS_MFE_PROXY = 'true';
       const mfConfig = MicrofrontendsServer.fromFile({
         filePath: join(fixtures, 'simple.jsonc'),
       }).config;
@@ -231,7 +228,6 @@ describe('withMicrofrontends: redirects', () => {
         next: nextConfig,
         app,
         microfrontend: mfConfig,
-        opts: { isProduction: false },
       });
 
       expect(newConfig.redirects).toBeUndefined();

packages/microfrontends/src/next/config/transforms/redirects.ts

@@ -1,14 +1,11 @@
-import { routeToLocalProxy } from '../../utils/route-to-local-proxy';
+import { localProxyIsRunning } from '../../../bin/local-proxy-is-running';
 import type { TransformConfigInput, TransformConfigResponse } from './types';
 
 export function transform(args: TransformConfigInput): TransformConfigResponse {
-  const { next, microfrontend, opts } = args;
-  const isProduction = opts?.isProduction ?? false;
+  const { next, microfrontend } = args;
 
   const requireLocalProxyHeader =
-    routeToLocalProxy() &&
-    !isProduction &&
-    !process.env.MFE_DISABLE_LOCAL_PROXY_REWRITE;
+    localProxyIsRunning() && !process.env.MFE_DISABLE_LOCAL_PROXY_REWRITE;
 
   if (requireLocalProxyHeader) {
     // If local proxy is running, redirect all requests without the header set by the local proxy to the local proxy.

packages/microfrontends/src/next/config/transforms/rewrites.test.ts

@@ -37,7 +37,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: { isProduction: true },
     });
 
     expect(newConfig.env).toEqual({
@@ -77,7 +76,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: { isProduction: true },
     });
 
     expect(newConfig.env).toEqual({
@@ -136,7 +134,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: { isProduction: true },
     });
 
     expect(newConfig.env).toEqual({
@@ -209,7 +206,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: { isProduction: true },
     });
 
     expect(newConfig.env).toEqual({
@@ -257,7 +253,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: { isProduction: true },
     });
 
     expect(newConfig.env).toEqual({
@@ -305,7 +300,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: { isProduction: true },
     });
 
     expect(newConfig.env).toEqual({
@@ -349,7 +343,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: { isProduction: true },
     });
 
     expect(newConfig.rewrites).toBeDefined();
@@ -375,9 +368,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: {
-        isProduction: false,
-      },
     });
 
     expect(newConfig).toMatchObject({});
@@ -399,7 +389,6 @@ describe('withMicrofrontends: rewrites', () => {
       next: nextConfig,
       app,
       microfrontend: mfConfig,
-      opts: { isProduction: true },
     });
 
     expect(newConfig.rewrites).toBeDefined();

packages/microfrontends/src/next/config/transforms/types.ts

@@ -6,7 +6,11 @@ import type {
 } from '../../../config/microfrontends-config/isomorphic/application';
 
 export interface TransformConfigOptions {
-  isProduction: boolean;
+  /**
+   * @deprecated this is a no-op, and will be removed in a future version.
+   * It is not necessary to specify this option.
+   */
+  isProduction?: boolean;
   supportPagesRouter?: boolean;
   // Prefer the legacy behavior of using webpack.EnvironmentPlugin instead of
   // Next.js's `defineServer` option, even when Next.js is new enough to support it.

packages/microfrontends/src/next/config/transforms/webpack.test.ts

@@ -64,7 +64,6 @@ describe('transform function', () => {
           app: currentApplication,
           microfrontend: microfrontends.config,
           opts: {
-            isProduction: true,
             preferWebpackEnvironmentPlugin,
           },
         });
@@ -102,7 +101,6 @@ describe('transform function', () => {
           app: currentApplication,
           microfrontend: microfrontends.config,
           opts: {
-            isProduction: true,
             preferWebpackEnvironmentPlugin,
           },
         });
@@ -145,7 +143,6 @@ describe('transform function', () => {
           app: currentApplication,
           microfrontend: microfrontends.config,
           opts: {
-            isProduction: true,
             preferWebpackEnvironmentPlugin,
           },
         });

packages/microfrontends/src/next/config/types.ts

@@ -10,7 +10,11 @@ export interface WithMicrofrontendsOptions {
    * if it differs from the project name.
    */
   appName?: string;
-  isProduction?: () => boolean;
+  /**
+   * @deprecated this is a no-op, and will be removed in a future version.
+   * It is not necessary to specify this option.
+   */
+  isProduction?: boolean;
   debug?: boolean;
   skipTransforms?: TransformKeys[];
   /**

packages/microfrontends/src/next/middleware/middleware.test.ts

@@ -116,7 +116,7 @@ describe('runMicrofrontendsMiddleware', () => {
   });
 
   it('rewrites requests to local proxy if running', async () => {
-    process.env.TURBO_TASK_HAS_MFE_PROXY = '1';
+    process.env.TURBO_TASK_HAS_MFE_PROXY = 'true';
     modifyRouting(config.applications.docs, {
       group: 'flagged',
       paths: ['/docs/flagged'],
@@ -138,7 +138,7 @@ describe('runMicrofrontendsMiddleware', () => {
   });
 
   it('does not rewrites to local proxy if disabled', async () => {
-    process.env.TURBO_TASK_HAS_MFE_PROXY = '1';
+    process.env.TURBO_TASK_HAS_MFE_PROXY = 'true';
     modifyRouting(config.applications.docs, {
       group: 'flagged',
       paths: ['/docs/flagged'],
@@ -153,9 +153,8 @@ describe('runMicrofrontendsMiddleware', () => {
     expect(response).toBeUndefined();
   });
 
-  it('does not use flag value if in production', async () => {
-    process.env.TURBO_TASK_HAS_MFE_PROXY = '1';
-    process.env.VERCEL_ENV = 'production';
+  it('does not use flag value if the local proxy is not running', async () => {
+    process.env.TURBO_TASK_HAS_MFE_PROXY = undefined;
     modifyRouting(config.applications.docs, {
       group: 'flagged',
       paths: ['/docs/flagged'],
@@ -175,7 +174,7 @@ describe('runMicrofrontendsMiddleware', () => {
   });
 
   it('does not execute flag if flag value header present', async () => {
-    process.env.TURBO_TASK_HAS_MFE_PROXY = '1';
+    process.env.TURBO_TASK_HAS_MFE_PROXY = 'true';
     modifyRouting(config.applications.docs, {
       group: 'flagged',
       paths: ['/docs/flagged'],
@@ -195,7 +194,7 @@ describe('runMicrofrontendsMiddleware', () => {
   });
 
   it('does rewrites if flag value header true', async () => {
-    process.env.TURBO_TASK_HAS_MFE_PROXY = '1';
+    process.env.TURBO_TASK_HAS_MFE_PROXY = 'true';
     modifyRouting(config.applications.docs, {
       group: 'flagged',
       paths: ['/docs/flagged'],
@@ -219,7 +218,7 @@ describe('runMicrofrontendsMiddleware', () => {
   });
 
   it('does not rewrites if flag value header true and mismatched path', async () => {
-    process.env.TURBO_TASK_HAS_MFE_PROXY = '1';
+    process.env.TURBO_TASK_HAS_MFE_PROXY = 'true';
     modifyRouting(config.applications.docs, {
       group: 'flagged',
       paths: ['/docs/flagged'],

packages/microfrontends/src/next/middleware/middleware.ts

@@ -6,7 +6,7 @@ import { pathToRegexp } from 'path-to-regexp';
 import type { ChildApplication } from '../../config/microfrontends-config/isomorphic/application';
 import { getWellKnownClientData } from '../../config/well-known/endpoints';
 import type { WellKnownClientData } from '../../config/well-known/types';
-import { routeToLocalProxy } from '../utils/route-to-local-proxy';
+import { localProxyIsRunning } from '../../bin/local-proxy-is-running';
 import { MicrofrontendConfigIsomorphic } from '../../config/microfrontends-config/isomorphic';
 import type {
   MicrofrontendsMiddleware,
@@ -43,9 +43,9 @@ function getFlagHandler({
   return async (req: NextRequest): Promise<NextResponse | undefined> => {
     try {
       const pathname = req.nextUrl.pathname;
-
+      const localProxyRunning = localProxyIsRunning();
       // If the pattern doesn't match, we don't need to execute the flag
-      const flagValueFromHeader = routeToLocalProxy()
+      const flagValueFromHeader = localProxyRunning
         ? getMfeFlagHeader(req)
         : null;
       if (pattern.test(pathname) && (flagValueFromHeader ?? (await flagFn()))) {
@@ -63,7 +63,7 @@ function getFlagHandler({
             headers,
           },
         };
-        if (routeToLocalProxy()) {
+        if (localProxyRunning) {
           if (process.env.MFE_DEBUG) {
             // eslint-disable-next-line no-console
             console.log(