feature(@nestjs/core) make cors middleware customizable

Author: kamilmysliwiec

src/common/interfaces/external/cors-options.interface.ts

@@ -0,0 +1,15 @@
+export type CustomOrigin = (
+  requestOrigin: string,
+  callback: (err: Error | null, allow?: boolean) => void,
+) => void;
+
+export interface CorsOptions {
+  origin?: boolean | string | RegExp | (string | RegExp)[] | CustomOrigin;
+  methods?: string | string[];
+  allowedHeaders?: string | string[];
+  exposedHeaders?: string | string[];
+  credentials?: boolean;
+  maxAge?: number;
+  preflightContinue?: boolean;
+  optionsSuccessStatus?: number;
+}

src/common/interfaces/nest-application-options.interface.ts

@@ -1,9 +1,10 @@
 import { HttpsOptions } from './https-options.interface';
 import { LoggerService } from '../services/logger.service';
 import { NestApplicationContextOptions } from './nest-application-context-options.interface';
+import { CorsOptions } from './external/cors-options.interface';
 
 export interface NestApplicationOptions extends NestApplicationContextOptions {
-  cors?: boolean;
+  cors?: boolean | CorsOptions;
   bodyParser?: boolean;
   httpsOptions?: HttpsOptions;
 }

src/common/interfaces/nest-application.interface.ts

@@ -3,6 +3,7 @@ import { WebSocketAdapter } from './web-socket-adapter.interface';
 import { CanActivate } from './can-activate.interface';
 import { NestInterceptor } from './nest-interceptor.interface';
 import { INestApplicationContext } from './nest-application-context.interface';
+import { CorsOptions } from './external/cors-options.interface';
 
 export interface INestApplication extends INestApplicationContext {
   /**
@@ -49,7 +50,7 @@ export interface INestApplication extends INestApplicationContext {
    *
    * @returns void
    */
-  enableCors(): this;
+  enableCors(options?: CorsOptions): this;
 
   /**
    * A wrapper function around native `express.disable()` method.

src/core/nest-application.ts

@@ -22,6 +22,7 @@ import {
   isNil,
   isUndefined,
   validatePath,
+  isObject,
 } from '@nestjs/common/utils/shared.utils';
 import { MicroserviceConfiguration } from '@nestjs/common/interfaces/microservices/microservice-configuration.interface';
 import { ExpressAdapter } from './adapters/express-adapter';
@@ -37,6 +38,7 @@ import { MiddlewaresContainer } from './middlewares/container';
 import { NestApplicationContext } from './nest-application-context';
 import { HttpsOptions } from '@nestjs/common/interfaces/https-options.interface';
 import { NestApplicationOptions } from '@nestjs/common/interfaces/nest-application-options.interface';
+import { CorsOptions } from '@nestjs/common/interfaces/external/cors-options.interface';
 
 const { SocketModule } =
   optional('@nestjs/websockets/socket-module') || ({} as any);
@@ -83,10 +85,14 @@ export class NestApplication extends NestApplicationContext
   }
 
   public applyOptions() {
-    if (!this.appOptions) {
+    if (!this.appOptions || !this.appOptions.cors) {
       return undefined;
     }
-    this.appOptions.cors && this.enableCors();
+    const isCorsOptionsObj = isObject(this.appOptions.cors);
+    if (!isCorsOptionsObj) {
+      return this.enableCors();
+    }
+    this.enableCors(this.appOptions.cors as CorsOptions);
   }
 
   public createServer(): any {
@@ -215,8 +221,8 @@ export class NestApplication extends NestApplicationContext
     return this;
   }
 
-  public enableCors(): this {
-    this.express.use(cors());
+  public enableCors(options?: CorsOptions): this {
+    this.express.use(cors(options));
     return this;
   }