fix: require serverMiddleware object with path and handler (#4656)

packages/server/src/server.js

@@ -176,7 +176,17 @@ export default class Server {
     // Resolve handler setup as string (path)
     if (typeof handler === 'string') {
       try {
-        handler = this.nuxt.resolver.requireModule(middleware.handler || middleware)
+        const requiredModuleFromHandlerPath = this.nuxt.resolver.requireModule(handler)
+
+        // In case the "handler" is not derived from an object but is a normal string, another object with
+        // path and handler could be the result
+
+        // If the required module has handler, treat the module as new "middleware" object
+        if (requiredModuleFromHandlerPath.handler) {
+          middleware = requiredModuleFromHandlerPath
+        }
+
+        handler = requiredModuleFromHandlerPath.handler || requiredModuleFromHandlerPath
       } catch (err) {
         if (!this.options.dev) {
           throw err[0]

test/fixtures/module/modules/middleware/midd3.js

@@ -0,0 +1,7 @@
+export default {
+  path: '/midd3',
+  handler(req, res) {
+    res.write('Be creative when writing test strings! Hey Mama :wave:')
+    res.end()
+  }
+}

test/fixtures/module/nuxt.config.js

@@ -12,7 +12,10 @@ export default {
     },
     ['./modules/template', { baz: 'ping' }]
   ],
-  serverMiddleware: ['./modules/middleware/midd2'],
+  serverMiddleware: [
+    './modules/middleware/midd2',
+    '~/modules/middleware/midd3'
+  ],
   hooks(hook) {
     hook('ready', (nuxt) => {
       nuxt.__ready_called__ = true

test/unit/module.test.js

@@ -54,6 +54,11 @@ describe('module', () => {
     expect(response).toBe('It works!')
   })
 
+  test('serverMiddleware with path', async () => {
+    const response = await rp(url('/midd3'))
+    expect(response).toBe('Be creative when writing test strings! Hey Mama :wave:')
+  })
+
   test('Hooks - Use external middleware before render', async () => {
     const response = await rp(url('/use-middleware'))
     expect(response).toBe('Use external middleware')