feat(core): middleware runs once for matching route

integration/hello-world/e2e/middleware-run-match-route.ts

@@ -0,0 +1,103 @@
+import {
+  Controller,
+  Get,
+  INestApplication,
+  Injectable,
+  MiddlewareConsumer,
+  NestMiddleware,
+  Module,
+} from '@nestjs/common';
+import { Test } from '../../../packages/testing';
+import * as request from 'supertest';
+import { expect } from 'chai';
+
+/**
+ * Number of times that the middleware was executed.
+ */
+let triggerCounter = 0;
+@Injectable()
+class Middleware implements NestMiddleware {
+  use(req, res, next) {
+    triggerCounter++;
+    next();
+  }
+}
+
+@Controller()
+class TestController {
+  @Get('/test')
+  testA() {}
+
+  @Get('/:id')
+  testB() {}
+
+  @Get('/:id/test')
+  testC() {}
+
+  @Get('/:id/:nested')
+  testD() {}
+}
+
+@Module({
+  controllers: [TestController],
+})
+class TestModule {
+  configure(consumer: MiddlewareConsumer) {
+    consumer.apply(Middleware).forRoutes(TestController);
+  }
+}
+
+describe('Middleware (run on route match)', () => {
+  let app: INestApplication;
+
+  beforeEach(async () => {
+    triggerCounter = 0;
+    app = (
+      await Test.createTestingModule({
+        imports: [TestModule],
+      }).compile()
+    ).createNestApplication();
+
+    await app.init();
+  });
+
+  it(`forRoutes(TestController) should execute middleware once when request url is equal match`, () => {
+    return request(app.getHttpServer())
+      .get('/test')
+      .expect(200)
+      .then(() => {
+        expect(triggerCounter).to.be.eq(1);
+      });
+  });
+
+  it(`forRoutes(TestController) should execute middleware once when request url is not equal match`, () => {
+    return request(app.getHttpServer())
+      .get('/1')
+      .expect(200)
+      .then(() => {
+        expect(triggerCounter).to.be.eq(1);
+      });
+  });
+
+  it(`forRoutes(TestController) should execute middleware once when request url is not of nested params`, () => {
+    return request(app.getHttpServer())
+      .get('/1/test')
+      .expect(200)
+      .then(() => {
+        expect(triggerCounter).to.be.eq(1);
+      });
+  });
+
+  it(`forRoutes(TestController) should execute middleware once when request url is of nested params`, () => {
+    return request(app.getHttpServer())
+      .get('/1/abc')
+      .expect(200)
+      .then(() => {
+        expect(triggerCounter).to.be.eq(1);
+      });
+  });
+
+  afterEach(async () => {
+    await app.close();
+  });
+});

packages/core/middleware/builder.ts

@@ -59,7 +59,8 @@ export class MiddlewareBuilder implements MiddlewareConsumer {
     ): MiddlewareConsumer {
       const { middlewareCollection } = this.builder;
 
-      const forRoutes = this.getRoutesFlatList(routes);
+      const flattedRoutes = this.getRoutesFlatList(routes);
+      const forRoutes = this.removeOverlappedRoutes(flattedRoutes);
       const configuration = {
         middleware: filterMiddleware(
           this.middleware,
@@ -82,5 +83,25 @@ export class MiddlewareBuilder implements MiddlewareConsumer {
         .flatten()
         .toArray();
     }
+
+    private removeOverlappedRoutes(routes: RouteInfo[]) {
+      const regexMatchParams = /(:[^\/]*)/g;
+      const wildcard = '([^/]*)';
+      const routesWithRegex = routes
+        .filter(route => route.path.indexOf(':') >= 0)
+        .map(route => ({
+          path: route.path,
+          regex: new RegExp(
+            '^(' + route.path.replace(regexMatchParams, wildcard) + ')$',
+            'g',
+          ),
+        }));
+      return routes.filter(route => {
+        const routeMatch = routesWithRegex.find(
+          v => route.path !== v.path && route.path.match(v.regex),
+        );
+        if (routeMatch === undefined) return route;
+      });
+    }
   };
 }