Add comprehensive security-headers e2e test suite

app/backend/test/security-headers.e2e-spec.ts

@@ -0,0 +1,239 @@
+import { INestApplication, VersioningType } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { Test, TestingModule } from '@nestjs/testing';
+import request from 'supertest';
+import {
+  buildCorsOptions,
+  createCorsOriginValidator,
+  createHelmetMiddleware,
+  createRateLimiter,
+} from '../src/common/security/security.module';
+import { RedisService } from '@liaoliaots/nestjs-redis';
+import RedisMock from 'ioredis-mock';
+import { Controller, Get, HttpCode } from '@nestjs/common';
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+@Controller()
+class TestController {
+  @Get('health')
+  @HttpCode(200)
+  getHealth() {
+    return { status: 'OK' };
+  }
+
+  @Get()
+  @HttpCode(200)
+  getRoot() {
+    return { message: 'OK' };
+  }
+}
+
+const createTestApp = async (): Promise<INestApplication> => {
+  const mockRedisInstance = new RedisMock();
+  const moduleFixture: TestingModule = await Test.createTestingModule({
+    imports: [
+      // ConfigModule is loaded via forRoot in the test; no need to import it
+      // here since ConfigModule.forRoot is already configured in the test.
+    ],
+    controllers: [TestController],
+    providers: [
+      {
+        provide: ConfigService,
+        useValue: {
+          get: jest.fn(<T = any>(key: string, defaultValue?: T): T | undefined => {
+            if (key === 'NODE_ENV') return (process.env.NODE_ENV ?? 'test') as unknown as T;
+            if (key === 'CORS_ORIGINS') return (process.env.CORS_ORIGINS ?? 'http://localhost:3000') as unknown as T;
+            if (key === 'CORS_ALLOW_CREDENTIALS') return (process.env.CORS_ALLOW_CREDENTIALS ?? 'false') as unknown as T;
+            if (key === 'RATE_LIMIT_LIMIT' || key === 'API_RATE_LIMIT') return '1000' as unknown as T;
+            if (key === 'RATE_LIMIT_WINDOW_MS' || key === 'THROTTLE_TTL') return '60000' as unknown as T;
+            return defaultValue;
+          }),
+        },
+      },
+      {
+        provide: RedisService,
+        useValue: {
+          getOrThrow: () => mockRedisInstance,
+        },
+      },
+    ],
+  }).compile();
+
+  const app = moduleFixture.createNestApplication();
+  app.getHttpAdapter().getInstance().disable('x-powered-by');
+
+  const configService = app.get(ConfigService);
+  app.use(createHelmetMiddleware(configService));
+  app.use(createCorsOriginValidator(configService));
+  app.enableCors(buildCorsOptions(configService));
+  app.use(createRateLimiter(configService, app.get(RedisService)));
+
+  app.setGlobalPrefix('api');
+  app.enableVersioning({
+    type: VersioningType.URI,
+    defaultVersion: '1',
+    prefix: 'v',
+  });
+
+  await app.init();
+  return app;
+};
+
+// Required security headers and their expected values (regex patterns)
+// These are derived from buildHelmetOptions in security.module.ts
+const REQUIRED_PRODUCTION_HEADERS: Record<string, RegExp | string> = {
+  'strict-transport-security': /max-age=31536000; includeSubDomains; preload/,
+  'x-content-type-options': 'nosniff',
+  'x-frame-options': 'DENY',
+  'referrer-policy': 'strict-origin-when-cross-origin',
+  'cross-origin-resource-policy': 'same-origin',
+  'cross-origin-opener-policy': 'same-origin',
+  'x-dns-prefetch-control': 'off',
+  'x-permitted-cross-domain-policies': 'none',
+  'content-security-policy': /default-src 'self'/,
+};
+
+// Headers that should be present in development mode too
+const REQUIRED_DEV_HEADERS: Record<string, RegExp | string> = {
+  'x-content-type-options': 'nosniff',
+  'x-frame-options': 'DENY',
+  'referrer-policy': 'strict-origin-when-cross-origin',
+  'cross-origin-resource-policy': 'same-origin',
+  'x-dns-prefetch-control': 'off',
+  'x-permitted-cross-domain-policies': 'none',
+};
+
+// Headers that MUST be absent in development mode
+const ABSENT_DEV_HEADERS = [
+  'strict-transport-security',
+  'content-security-policy',
+  'cross-origin-opener-policy',
+];
+
+const setEnv = (vars: Record<string, string | undefined>) => {
+  for (const [key, value] of Object.entries(vars)) {
+    if (value === undefined) {
+      delete process.env[key];
+    } else {
+      process.env[key] = value;
+    }
+  }
+};
+
+// ---------------------------------------------------------------------------
+// Tests
+// ---------------------------------------------------------------------------
+
+describe('Security Headers (e2e)', () => {
+  let originalEnv: Record<string, string | undefined>;
+
+  beforeAll(() => {
+    originalEnv = {
+      NODE_ENV: process.env.NODE_ENV,
+      CORS_ORIGINS: process.env.CORS_ORIGINS,
+      CORS_ALLOW_CREDENTIALS: process.env.CORS_ALLOW_CREDENTIALS,
+    };
+  });
+
+  afterAll(() => {
+    setEnv(originalEnv);
+  });
+
+  describe('Production mode', () => {
+    let app: INestApplication;
+
+    beforeAll(async () => {
+      setEnv({
+        NODE_ENV: 'production',
+        CORS_ORIGINS: 'https://api.chainforge.app',
+        CORS_ALLOW_CREDENTIALS: 'false',
+      });
+      app = await createTestApp();
+    });
+
+    afterAll(async () => {
+      await app.close();
+    });
+
+    it('should include all required security headers with correct values', async () => {
+      const response = await request(app.getHttpServer()).get('/api/v1/health');
+
+      for (const [header, expected] of Object.entries(REQUIRED_PRODUCTION_HEADERS)) {
+        expect(response.headers[header]).toBeDefined();
+        if (expected instanceof RegExp) {
+          expect(response.headers[header]).toMatch(expected);
+        } else {
+          expect(response.headers[header]).toBe(expected);
+        }
+      }
+    });
+
+    it('should NOT include the x-powered-by header', async () => {
+      const response = await request(app.getHttpServer()).get('/api/v1/health');
+      expect(response.headers['x-powered-by']).toBeUndefined();
+    });
+
+    it('should include report-uri in Content-Security-Policy header', async () => {
+      const response = await request(app.getHttpServer()).get('/api/v1/health');
+      const csp = response.headers['content-security-policy'] as string;
+      expect(csp).toBeDefined();
+      // The CSP report-uri directive tells the browser where to send violation reports
+      expect(csp).toContain('/api/v1/csp-report');
+    });
+
+    it('should include preload directive in Strict-Transport-Security', async () => {
+      const response = await request(app.getHttpServer()).get('/api/v1/health');
+      const hsts = response.headers['strict-transport-security'] as string;
+      expect(hsts).toBeDefined();
+      expect(hsts).toContain('preload');
+      expect(hsts).toContain('includeSubDomains');
+      expect(hsts).toContain('max-age=31536000');
+    });
+  });
+
+  describe('Development mode', () => {
+    let app: INestApplication;
+
+    beforeAll(async () => {
+      setEnv({
+        NODE_ENV: 'development',
+        CORS_ORIGINS: 'http://localhost:3000',
+        CORS_ALLOW_CREDENTIALS: 'false',
+      });
+      app = await createTestApp();
+    });
+
+    afterAll(async () => {
+      await app.close();
+    });
+
+    it('should include dev-appropriate security headers', async () => {
+      const response = await request(app.getHttpServer()).get('/api/v1/health');
+
+      for (const [header, expected] of Object.entries(REQUIRED_DEV_HEADERS)) {
+        expect(response.headers[header]).toBeDefined();
+        if (expected instanceof RegExp) {
+          expect(response.headers[header]).toMatch(expected);
+        } else {
+          expect(response.headers[header]).toBe(expected);
+        }
+      }
+    });
+
+    it('should NOT include production-only headers in dev mode', async () => {
+      const response = await request(app.getHttpServer()).get('/api/v1/health');
+
+      for (const header of ABSENT_DEV_HEADERS) {
+        expect(response.headers[header]).toBeUndefined();
+      }
+    });
+
+    it('should not include x-powered-by header', async () => {
+      const response = await request(app.getHttpServer()).get('/api/v1/health');
+      expect(response.headers['x-powered-by']).toBeUndefined();
+    });
+  });
+});