feat(@nestjs/core): Add RouterModule to the core

packages/common/test/utils/shared.utils.spec.ts

@@ -88,10 +88,20 @@ describe('Shared utils', () => {
     it('should returns same path', () => {
       expect(validatePath('/nope')).to.be.eql('/nope');
     });
-    it('should returns empty path', () => {
-      expect(validatePath('')).to.be.eql('');
-      expect(validatePath(null)).to.be.eql('');
-      expect(validatePath(undefined)).to.be.eql('');
+    it('should remove all trailing slashes at the end of the path', () => {
+      expect(validatePath('path/')).to.be.eql('/path');
+      expect(validatePath('path///')).to.be.eql('/path');
+      expect(validatePath('/path/path///')).to.be.eql('/path/path');
+    });
+    it('should replace all slashes with only one slash', () => {
+      expect(validatePath('////path/')).to.be.eql('/path');
+      expect(validatePath('///')).to.be.eql('/');
+      expect(validatePath('/path////path///')).to.be.eql('/path/path');
+    });
+    it('should returns / for empty path', () => {
+      expect(validatePath('')).to.be.eql('/');
+      expect(validatePath(null)).to.be.eql('/');
+      expect(validatePath(undefined)).to.be.eql('/');
     });
   });
   describe('isNil', () => {

packages/common/utils/shared.utils.ts

@@ -21,7 +21,11 @@ export const isPlainObject = (fn: any): fn is object => {
   );
 };
 export const validatePath = (path?: string): string =>
-  path ? (path.charAt(0) !== '/' ? '/' + path : path) : '';
+  path
+    ? path.startsWith('/')
+      ? ('/' + path.replace(/\/+$/, '')).replace(/\/+/g, '/')
+      : '/' + path.replace(/\/+$/, '')
+    : '/';
 export const isFunction = (fn: any): boolean => typeof fn === 'function';
 export const isString = (fn: any): fn is string => typeof fn === 'string';
 export const isConstructor = (fn: any): boolean => fn === 'constructor';

packages/core/router/interfaces/routes.interface.ts

@@ -0,0 +1,25 @@
+import { Type } from '@nestjs/common';
+
+/**
+ * Defines the Routes Tree
+ * - `path` - a string describe the Module path which will be applied
+ * to all it's controllers and childs
+ * - `module` - the parent Module.
+ * - `children` - an array of child Modules.
+ */
+export interface Route {
+  path: string;
+  module?: Type<any>;
+  children?: Routes | Type<any>[];
+}
+
+/**
+ * Defines the Routes Tree
+ * - `path` - a string describe the Module path which will be applied
+ * to all it's controllers and childs
+ * - `module` - the parent Module.
+ * - `children` - an array of child Modules.
+ *
+ * @publicapi
+ */
+export type Routes = Route[];

packages/core/router/router-explorer.ts

@@ -89,7 +89,11 @@ export class RouterExplorer {
     prefix?: string,
   ): string {
     let path = Reflect.getMetadata(PATH_METADATA, metatype);
-    if (prefix) path = prefix + this.validateRoutePath(path);
+    if (prefix) {
+      path = prefix + this.validateRoutePath(path);
+      // Override the metadata with the new path
+      Reflect.defineMetadata(PATH_METADATA, path, metatype);
+    }
     return this.validateRoutePath(path);
   }
 

packages/core/router/router.module.ts

@@ -0,0 +1,36 @@
+import { Module, DynamicModule } from '@nestjs/common';
+import { validatePath } from '@nestjs/common/utils/shared.utils';
+import { MODULE_PATH } from '@nestjs/common/constants';
+import { Routes } from './interfaces/routes.interface';
+import { flatRoutes } from './utils/flat-routes.util';
+
+/**
+ * A Utility Module to Organize your Routes,
+ *
+ * @publicApi
+ */
+@Module({})
+export class RouterModule {
+  /**
+   * takes an array of modules and organize them in hierarchy way
+   * @param {Routes} routes Array of Routes
+   * @publicapi
+   */
+  static register(routes: Routes): DynamicModule {
+    RouterModule.buildPathMap(routes);
+    return {
+      module: RouterModule,
+    };
+  }
+
+  private static buildPathMap(routes: Routes) {
+    const flattenRoutes = flatRoutes(routes);
+    flattenRoutes.forEach(route => {
+      Reflect.defineMetadata(
+        MODULE_PATH,
+        validatePath(route.path),
+        route.module,
+      );
+    });
+  }
+}

packages/core/router/utils/flat-routes.util.ts

@@ -0,0 +1,28 @@
+import { Routes } from '../interfaces/routes.interface';
+import { validatePath } from '@nestjs/common/utils/shared.utils';
+
+export function flatRoutes(routes: Routes, result = []) {
+  routes.forEach(element => {
+    if (element.module && element.path) {
+      result.push(element);
+    }
+    if (element.children) {
+      const childrenRef = element.children as Routes;
+      childrenRef.forEach(child => {
+        if (!(typeof child === 'string') && child.path) {
+          child.path = validatePath(
+            validatePath(element.path) + validatePath(child.path),
+          );
+        } else {
+          result.push({ path: element.path, module: child });
+        }
+      });
+      return flatRoutes(childrenRef, result);
+    }
+  });
+  result.forEach(route => {
+    // clean up
+    delete route.children;
+  });
+  return result;
+}

packages/core/test/router/router.module.spec.ts

@@ -0,0 +1,74 @@
+import { RouterModule } from '../../router/router.module';
+import { Module, Controller } from '@nestjs/common';
+import { MODULE_PATH } from '@nestjs/common/constants';
+import { Test } from '@nestjs/testing';
+import { INestApplication } from '@nestjs/common';
+import { Routes } from '../../router/interfaces/routes.interface';
+import { expect } from 'chai';
+
+describe('RouterModule', () => {
+  let app: INestApplication;
+
+  @Controller('/parent-controller')
+  class ParentController {}
+  @Controller('/child-controller')
+  class ChildController {}
+  @Controller('no-slash-controller')
+  class NoSlashController {}
+
+  class UnknownController {}
+  @Module({ controllers: [ParentController] })
+  class ParentModule {}
+
+  @Module({ controllers: [ChildController] })
+  class ChildModule {}
+
+  @Module({})
+  class AuthModule {}
+  @Module({})
+  class PaymentsModule {}
+
+  @Module({ controllers: [NoSlashController] })
+  class NoSlashModule {}
+
+  const routes1: Routes = [
+    {
+      path: 'parent',
+      module: ParentModule,
+      children: [
+        {
+          path: 'child',
+          module: ChildModule,
+        },
+      ],
+    },
+  ];
+
+  const routes2: Routes = [
+    { path: 'v1', children: [AuthModule, PaymentsModule] },
+  ];
+
+  @Module({
+    imports: [ParentModule, ChildModule, RouterModule.register(routes1)],
+  })
+  class MainModule {}
+
+  @Module({
+    imports: [AuthModule, PaymentsModule, RouterModule.register(routes2)],
+  })
+  class AppModule {}
+
+  it('should add Path Metadata to all Routes', () => {
+    const parentPath = Reflect.getMetadata(MODULE_PATH, ParentModule);
+    const childPath = Reflect.getMetadata(MODULE_PATH, ChildModule);
+    expect(parentPath).to.be.equal('/parent');
+    expect(childPath).to.be.equal('/parent/child');
+  });
+
+  it('should add paths even we omitted the module key', () => {
+    const authPath = Reflect.getMetadata(MODULE_PATH, AuthModule);
+    const paymentPath = Reflect.getMetadata(MODULE_PATH, PaymentsModule);
+    expect(authPath).to.be.equal('/v1');
+    expect(paymentPath).to.be.equal('/v1');
+  });
+});

packages/core/test/router/utils/flat-routes.spec.ts

@@ -0,0 +1,87 @@
+import { expect } from 'chai';
+import { flatRoutes } from '../../../router/utils/flat-routes.util';
+import { Module } from '@nestjs/common';
+describe('FlatRoutes', () => {
+  it('should flat all Routes, and we could also ommit the path', () => {
+    @Module({})
+    class ParentModule {}
+    @Module({})
+    class ChildModule {}
+    @Module({})
+    class ChildChildModule {}
+    @Module({})
+    class ChildModule2 {}
+    @Module({})
+    class ParentChildModule {}
+    @Module({})
+    class ChildChildModule2 {}
+    @Module({})
+    class AuthModule {}
+    @Module({})
+    class CatsModule {}
+    @Module({})
+    class DogsModule {}
+
+    @Module({})
+    class AuthModule2 {}
+    @Module({})
+    class CatsModule2 {}
+    @Module({})
+    class CatsModule3 {}
+    @Module({})
+    class AuthModule3 {}
+    const routes = [
+      {
+        path: '/parent',
+        module: ParentModule,
+        children: [
+          {
+            path: '/child',
+            module: ChildModule,
+            children: [
+              { path: '/child2', module: ChildModule2 },
+              {
+                path: '/parentchild',
+                module: ParentChildModule,
+                children: [
+                  {
+                    path: '/childchild',
+                    module: ChildChildModule,
+                    children: [
+                      { path: '/child2child', module: ChildChildModule2 },
+                    ],
+                  },
+                ],
+              },
+            ],
+          },
+        ],
+      },
+      { path: '/v1', children: [AuthModule, CatsModule, DogsModule] },
+      { path: '/v2', children: [AuthModule2, CatsModule2] },
+      { path: '/v3', children: [AuthModule3, CatsModule3] },
+    ];
+    const expectedRoutes = [
+      { path: '/parent', module: ParentModule },
+      { path: '/parent/child', module: ChildModule },
+      { path: '/parent/child/child2', module: ChildModule2 },
+      { path: '/parent/child/parentchild', module: ParentChildModule },
+      {
+        path: '/parent/child/parentchild/childchild',
+        module: ChildChildModule,
+      },
+      {
+        path: '/parent/child/parentchild/childchild/child2child',
+        module: ChildChildModule2,
+      },
+      { path: '/v1', module: AuthModule },
+      { path: '/v1', module: CatsModule },
+      { path: '/v1', module: DogsModule },
+      { path: '/v2', module: AuthModule2 },
+      { path: '/v2', module: CatsModule2 },
+      { path: '/v3', module: AuthModule3 },
+      { path: '/v3', module: CatsModule3 },
+    ];
+    expect(flatRoutes(routes)).to.be.eql(expectedRoutes);
+  });
+});