Added an HTTP interceptor [#328]

 * Attaches the authentication token if one is currently held.

comixed-web/src/app/app.constants.ts

@@ -0,0 +1,21 @@
+/*
+ * ComiXed - A digital comic book library management application.
+ * Copyright (C) 2020, The ComiXed Project
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses>
+ */
+
+export const HTTP_AUTHORIZATION_HEADER = 'Authorization';
+export const HTTP_REQUESTED_WITH_HEADER = 'X-Requested-With';
+export const HTTP_XML_REQUEST = 'XMLHttpRequest';

comixed-web/src/app/app.module.ts

@@ -21,11 +21,15 @@ import { NgModule } from '@angular/core';
 import { AppRoutingModule } from './app-routing.module';
 import { AppComponent } from './app.component';
 import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
+import { HTTP_INTERCEPTORS } from '@angular/common/http';
+import { HttpInterceptor } from '@app/interceptors/http.interceptor';
 
 @NgModule({
   declarations: [AppComponent],
   imports: [BrowserModule, AppRoutingModule, BrowserAnimationsModule],
-  providers: [],
+  providers: [
+    [{ provide: HTTP_INTERCEPTORS, useClass: HttpInterceptor, multi: true }]
+  ],
   bootstrap: [AppComponent]
 })
 export class AppModule {}

comixed-web/src/app/interceptors/http.interceptor.spec.ts

@@ -0,0 +1,119 @@
+/*
+ * ComiXed - A digital comic book library management application.
+ * Copyright (C) 2020, The ComiXed Project
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses>
+ */
+
+import { TestBed } from '@angular/core/testing';
+import { HttpInterceptor } from './http.interceptor';
+import { LoggerModule } from '@angular-ru/logger';
+import { TokenService } from '@app/core';
+import { CoreModule } from '@app/core/core.module';
+import { AUTHENTICATION_TOKEN } from '@app/core/core.fixtures';
+import {
+  HttpClientTestingModule,
+  HttpTestingController,
+  TestRequest
+} from '@angular/common/http/testing';
+import { Injectable } from '@angular/core';
+import { Observable } from 'rxjs';
+import { HTTP_INTERCEPTORS, HttpClient } from '@angular/common/http';
+import {
+  HTTP_AUTHORIZATION_HEADER,
+  HTTP_REQUESTED_WITH_HEADER,
+  HTTP_XML_REQUEST
+} from '@app/app.constants';
+
+const TEST_REQUEST_URL = 'http://localhost';
+
+@Injectable()
+class TestService {
+  constructor(private http: HttpClient) {}
+
+  request(): Observable<any> {
+    return this.http.get(TEST_REQUEST_URL);
+  }
+}
+
+describe('HttpInterceptor', () => {
+  let interceptor: HttpInterceptor;
+  let tokenService: jasmine.SpyObj<TokenService>;
+  let httpMock: HttpTestingController;
+  let testService: TestService;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      imports: [CoreModule, HttpClientTestingModule, LoggerModule.forRoot()],
+      providers: [
+        { provide: HTTP_INTERCEPTORS, useClass: HttpInterceptor, multi: true },
+        TestService,
+        {
+          provide: TokenService,
+          useValue: {
+            hasAuthToken: jasmine.createSpy('TokenService.hasAuthToken()'),
+            getAuthToken: jasmine.createSpy('TokenService.getAuthToken()')
+          }
+        }
+      ]
+    });
+
+    tokenService = TestBed.inject(TokenService) as jasmine.SpyObj<TokenService>;
+    httpMock = TestBed.inject(HttpTestingController);
+    testService = TestBed.inject(TestService);
+  });
+
+  describe('when no authentication token is present', () => {
+    let req: TestRequest;
+
+    beforeEach(() => {
+      tokenService.hasAuthToken.and.returnValue(false);
+      testService.request().subscribe(() => {});
+      req = httpMock.expectOne(TEST_REQUEST_URL);
+    });
+
+    it('does not contain an authorization header', () => {
+      expect(req.request.headers.get(HTTP_AUTHORIZATION_HEADER)).toBeNull();
+    });
+
+    it('attaches a requested with header', () => {
+      expect(req.request.headers.get(HTTP_REQUESTED_WITH_HEADER)).toEqual(
+        HTTP_XML_REQUEST
+      );
+    });
+  });
+
+  describe('when an authentication token is present', () => {
+    let req: TestRequest;
+
+    beforeEach(() => {
+      tokenService.hasAuthToken.and.returnValue(true);
+      tokenService.getAuthToken.and.returnValue(AUTHENTICATION_TOKEN);
+      testService.request().subscribe(() => {});
+      req = httpMock.expectOne(TEST_REQUEST_URL);
+    });
+
+    it('attaches the token as a request header', () => {
+      expect(req.request.headers.get(HTTP_AUTHORIZATION_HEADER)).toEqual(
+        `Bearer ${AUTHENTICATION_TOKEN}`
+      );
+    });
+
+    it('attaches a requested with header', () => {
+      expect(req.request.headers.get(HTTP_REQUESTED_WITH_HEADER)).toEqual(
+        HTTP_XML_REQUEST
+      );
+    });
+  });
+});

comixed-web/src/app/interceptors/http.interceptor.ts

@@ -0,0 +1,64 @@
+/*
+ * ComiXed - A digital comic book library management application.
+ * Copyright (C) 2020, The ComiXed Project
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses>
+ */
+
+import { Injectable } from '@angular/core';
+import { HttpEvent, HttpHandler, HttpRequest } from '@angular/common/http';
+import { Observable } from 'rxjs';
+import { LoggerService } from '@angular-ru/logger';
+import { TokenService } from '@app/core';
+import {
+  HTTP_AUTHORIZATION_HEADER,
+  HTTP_REQUESTED_WITH_HEADER,
+  HTTP_XML_REQUEST
+} from '@app/app.constants';
+import { retry, tap } from 'rxjs/operators';
+
+@Injectable()
+export class HttpInterceptor implements HttpInterceptor {
+  constructor(
+    private logger: LoggerService,
+    private tokenService: TokenService
+  ) {}
+
+  intercept(
+    request: HttpRequest<unknown>,
+    next: HttpHandler
+  ): Observable<HttpEvent<unknown>> {
+    let requestClone = request.clone({
+      headers: request.headers.set(HTTP_REQUESTED_WITH_HEADER, HTTP_XML_REQUEST)
+    });
+
+    this.logger.trace('Processing outgoing HTTP request');
+    if (this.tokenService.hasAuthToken()) {
+      this.logger.trace('Adding authentication token to request');
+      const token = this.tokenService.getAuthToken();
+      requestClone = requestClone.clone({
+        headers: requestClone.headers.set(
+          HTTP_AUTHORIZATION_HEADER,
+          `Bearer ${token}`
+        )
+      });
+    }
+    return next.handle(requestClone).pipe(
+      retry(3),
+      tap(response => {
+        this.logger.trace('Response received:', response);
+      })
+    );
+  }
+}