fix(core): detect conventional middleware class nestjs#6586

Author: Clay Risser

packages/core/middleware/utils.ts

@@ -29,7 +29,7 @@ export const mapToClass = <T extends Function | Type<any>>(
   excludedRoutes: RouteInfoRegex[],
   httpAdapter: HttpServer,
 ) => {
-  if (isClass(middleware)) {
+  if (isMiddlewareClass(middleware)) {
     if (excludedRoutes.length <= 0) {
       return middleware;
     }
@@ -59,8 +59,17 @@ export const mapToClass = <T extends Function | Type<any>>(
   );
 };
 
-export function isClass(middleware: any): middleware is Type<any> {
-  return middleware.toString().substring(0, 5) === 'class';
+export function isMiddlewareClass(middleware: any): middleware is Type<any> {
+  const middlewareStr = middleware.toString();
+  if (middlewareStr.substring(0, 5) === 'class') {
+    return true;
+  }
+  const middlewareArr = middlewareStr.split(' ');
+  return (
+    middlewareArr[0] === 'function' &&
+    /[A-Z]/.test(middlewareArr[1]?.[0]) &&
+    typeof middleware.prototype?.use === 'function'
+  );
 }
 
 export function assignToken(metatype: Type<any>, token = uuid()): Type<any> {

packages/core/test/middleware/utils.spec.ts

@@ -5,7 +5,7 @@ import * as sinon from 'sinon';
 import {
   assignToken,
   filterMiddleware,
-  isClass,
+  isMiddlewareClass,
   isRouteExcluded,
   mapToClass,
 } from '../../middleware/utils';
@@ -63,15 +63,15 @@ describe('middleware utils', () => {
       });
     });
   });
-  describe('isClass', () => {
+  describe('isMiddlewareClass', () => {
     describe('when middleware is a class', () => {
       it('should returns true', () => {
-        expect(isClass(Test)).to.be.true;
+        expect(isMiddlewareClass(Test)).to.be.true;
       });
     });
     describe('when middleware is a function', () => {
       it('should returns false', () => {
-        expect(isClass(fnMiddleware)).to.be.false;
+        expect(isMiddlewareClass(fnMiddleware)).to.be.false;
       });
     });
   });