Merge pull request nestjs#6573 from MyAeroCode/lutz-feat/route-injection

feat(core): support route injection

Author: kamilmysliwiec

packages/core/router/router-explorer.ts

@@ -124,22 +124,23 @@ export class RouterExplorer {
     prototype: object,
     methodName: string,
   ): RoutePathProperties {
-    const targetCallback = prototype[methodName];
-    const routePath = Reflect.getMetadata(PATH_METADATA, targetCallback);
+    const instanceCallback = instance[methodName];
+    const prototypeCallback = prototype[methodName];
+    const routePath = Reflect.getMetadata(PATH_METADATA, prototypeCallback);
     if (isUndefined(routePath)) {
       return null;
     }
     const requestMethod: RequestMethod = Reflect.getMetadata(
       METHOD_METADATA,
-      targetCallback,
+      prototypeCallback,
     );
     const path = isString(routePath)
       ? [addLeadingSlash(routePath)]
       : routePath.map(p => addLeadingSlash(p));
     return {
       path,
       requestMethod,
-      targetCallback,
+      targetCallback: instanceCallback,
       methodName,
     };
   }

packages/core/test/router/router-explorer.spec.ts

@@ -109,55 +109,133 @@ describe('RouterExplorer', () => {
       const instanceProto = Object.getPrototypeOf(instance);
 
       const route = routerBuilder.exploreMethodMetadata(
-        new TestRoute(),
+        instance,
         instanceProto,
         'getTest',
       );
 
       expect(route.path).to.eql(['/test']);
       expect(route.requestMethod).to.eql(RequestMethod.GET);
+      expect(route.targetCallback).to.eq(instance.getTest);
     });
 
     it('should method return expected object which represent single route with alias', () => {
       const instance = new TestRouteAlias();
       const instanceProto = Object.getPrototypeOf(instance);
 
       const route = routerBuilder.exploreMethodMetadata(
-        new TestRouteAlias(),
+        instance,
         instanceProto,
         'getTest',
       );
 
       expect(route.path).to.eql(['/test']);
       expect(route.requestMethod).to.eql(RequestMethod.GET);
+      expect(route.targetCallback).to.eq(instance.getTest);
     });
 
     it('should method return expected object which represent multiple routes', () => {
       const instance = new TestRoute();
       const instanceProto = Object.getPrototypeOf(instance);
 
       const route = routerBuilder.exploreMethodMetadata(
-        new TestRoute(),
+        instance,
         instanceProto,
         'getTestUsingArray',
       );
 
       expect(route.path).to.eql(['/foo', '/bar']);
       expect(route.requestMethod).to.eql(RequestMethod.GET);
+      expect(route.targetCallback).to.eq(instance.getTestUsingArray);
     });
 
     it('should method return expected object which represent multiple routes with alias', () => {
       const instance = new TestRouteAlias();
       const instanceProto = Object.getPrototypeOf(instance);
 
       const route = routerBuilder.exploreMethodMetadata(
-        new TestRouteAlias(),
+        instance,
         instanceProto,
         'getTestUsingArray',
       );
 
       expect(route.path).to.eql(['/foo', '/bar']);
       expect(route.requestMethod).to.eql(RequestMethod.GET);
+      expect(route.targetCallback).to.eq(instance.getTestUsingArray);
+    });
+
+    describe('when new implementation is injected into router', () => {
+      it('should method return changed impl of single route', () => {
+        const instance = new TestRoute();
+        const instanceProto = Object.getPrototypeOf(instance);
+
+        const newImpl = function () {};
+        instance.getTest = newImpl;
+
+        const route = routerBuilder.exploreMethodMetadata(
+          instance,
+          instanceProto,
+          'getTest',
+        );
+
+        expect(route.targetCallback).to.eq(newImpl);
+        expect(route.path).to.eql(['/test']);
+        expect(route.requestMethod).to.eql(RequestMethod.GET);
+      });
+
+      it('should method return changed impl of single route which alias applied', () => {
+        const instance = new TestRouteAlias();
+        const instanceProto = Object.getPrototypeOf(instance);
+
+        const newImpl = function () {};
+        instance.getTest = newImpl;
+
+        const route = routerBuilder.exploreMethodMetadata(
+          instance,
+          instanceProto,
+          'getTest',
+        );
+
+        expect(route.targetCallback).to.eq(newImpl);
+        expect(route.path).to.eql(['/test']);
+        expect(route.requestMethod).to.eql(RequestMethod.GET);
+      });
+
+      it('should method return changed impl of multiple routes', () => {
+        const instance = new TestRoute();
+        const instanceProto = Object.getPrototypeOf(instance);
+
+        const newImpl = function () {};
+        instance.getTestUsingArray = newImpl;
+
+        const route = routerBuilder.exploreMethodMetadata(
+          instance,
+          instanceProto,
+          'getTestUsingArray',
+        );
+
+        expect(route.targetCallback).to.eq(newImpl);
+        expect(route.path).to.eql(['/foo', '/bar']);
+        expect(route.requestMethod).to.eql(RequestMethod.GET);
+      });
+
+      it('should method return changed impl of multiple routes which alias applied', () => {
+        const instance = new TestRouteAlias();
+        const instanceProto = Object.getPrototypeOf(instance);
+
+        const newImpl = function () {};
+        instance.getTestUsingArray = newImpl;
+
+        const route = routerBuilder.exploreMethodMetadata(
+          instance,
+          instanceProto,
+          'getTestUsingArray',
+        );
+
+        expect(route.targetCallback).to.eq(newImpl);
+        expect(route.path).to.eql(['/foo', '/bar']);
+        expect(route.requestMethod).to.eql(RequestMethod.GET);
+      });
     });
   });