令牌刷新后的Angular 4 Interceptor重试请求

Question

您好我正在尝试通过刷新令牌并重试请求来弄清楚如何实现新的角度拦截器并处理401 unauthorized错误。这是我一直关注的指南：https://ryanchenkie.com/angular-authentication-using-the-http-client-and-http-interceptors

我成功缓存了失败的请求并可以刷新令牌，但我无法弄清楚如何重新发送先前失败的请求。我也想让这个与我目前正在使用的解析器一起使用。

token.interceptor.ts

return next.handle( request ).do(( event: HttpEvent<any> ) => {
        if ( event instanceof HttpResponse ) {
            // do stuff with response if you want
        }
    }, ( err: any ) => {
        if ( err instanceof HttpErrorResponse ) {
            if ( err.status === 401 ) {
                console.log( err );
                this.auth.collectFailedRequest( request );
                this.auth.refreshToken().subscribe( resp => {
                    if ( !resp ) {
                        console.log( "Invalid" );
                    } else {
                        this.auth.retryFailedRequests();
                    }
                } );

            }
        }
    } );

authentication.service.ts

cachedRequests: Array<HttpRequest<any>> = [];

public collectFailedRequest ( request ): void {
    this.cachedRequests.push( request );
}

public retryFailedRequests (): void {
    // retry the requests. this method can
    // be called after the token is refreshed
    this.cachedRequests.forEach( request => {
        request = request.clone( {
            setHeaders: {
                Accept: 'application/json',
                'Content-Type': 'application/json',
                Authorization: `Bearer ${ this.getToken() }`
            }
        } );
        //??What to do here
    } );
}

上面的retryFailedRequests（）文件是我无法弄清楚的。如何重新发送请求并在重试后通过解析程序将其提供给路由？

如果有帮助，这是所有相关代码：https://gist.github.com/joshharms/00d8159900897dc5bed45757e30405f9

Answer 1

我的最终解决方案。适用于并行请求。

export class AuthInterceptor implements HttpInterceptor {

    authService;
    refreshTokenInProgress = false;

    tokenRefreshedSource = new Subject();
    tokenRefreshed$ = this.tokenRefreshedSource.asObservable();

    constructor(private injector: Injector, private router: Router, private snackBar: MdSnackBar) {}

    addAuthHeader(request) {
        const authHeader = this.authService.getAuthorizationHeader();
        if (authHeader) {
            return request.clone({
                setHeaders: {
                    "Authorization": authHeader
                }
            });
        }
        return request;
    }

    refreshToken() {
        if (this.refreshTokenInProgress) {
            return new Observable(observer => {
                this.tokenRefreshed$.subscribe(() => {
                    observer.next();
                    observer.complete();
                });
            });
        } else {
            this.refreshTokenInProgress = true;

            return this.authService.refreshToken()
               .do(() => {
                    this.refreshTokenInProgress = false;
                    this.tokenRefreshedSource.next();
                });
        }
    }

    logout() {
        this.authService.logout();
        this.router.navigate(["login"]);
    }

    intercept(request: HttpRequest<any>, next: HttpHandler): Observable<any> {
        this.authService = this.injector.get(AuthService);

        // Handle request
        request = this.addAuthHeader(request);

        // Handle response
        return next.handle(request).catch(error => {

            if (error.status === 401) {
                return this.refreshToken()
                    .switchMap(() => {
                        request = this.addAuthHeader(request);
                        return next.handle(request);
                    })
                    .catch(() => {
                        this.logout();
                        return Observable.empty();
                    });
            }

            return Observable.throw(error);
        });
    }
}

Answer 2

我遇到了类似的问题，我认为收集/重试逻辑过于复杂。相反，我们可以使用catch运算符来检查401，然后监视令牌刷新，并重新运行请求：

return next.handle(this.applyCredentials(req))
  .catch((error, caught) => {
    if (!this.isAuthError(error)) {
      throw error;
    }
    return this.auth.refreshToken().first().flatMap((resp) => {
      if (!resp) {
        throw error;
      }
      return next.handle(this.applyCredentials(req));
    });
  }) as any;

...

private isAuthError(error: any): boolean {
  return error instanceof HttpErrorResponse && error.status === 401;
}

Answer 3

使用最新版本的Angular（7.0.0）和rxjs（6.3.3），这就是我创建功能齐全的Auto Session Recovery拦截器的方式，从而确保如果并发请求失败并返回401，那么它也只能命中令牌刷新API一次，然后使用switchMap和Subject将失败的请求传递给请求的响应。下面是我的拦截器代码的样子。我已经省略了身份验证服务和存储服务的代码，因为它们是非常标准的服务类。

import {
  HttpErrorResponse,
  HttpEvent,
  HttpHandler,
  HttpInterceptor,
  HttpRequest
} from "@angular/common/http";
import { Injectable } from "@angular/core";
import { Observable, Subject, throwError } from "rxjs";
import { catchError, switchMap } from "rxjs/operators";

import { AuthService } from "../auth/auth.service";
import { STATUS_CODE } from "../error-code";
import { UserSessionStoreService as StoreService } from "../store/user-session-store.service";

@Injectable()
export class SessionRecoveryInterceptor implements HttpInterceptor {
  constructor(
    private readonly store: StoreService,
    private readonly sessionService: AuthService
  ) {}

  private _refreshSubject: Subject<any> = new Subject<any>();

  private _ifTokenExpired() {
    this._refreshSubject.subscribe({
      complete: () => {
        this._refreshSubject = new Subject<any>();
      }
    });
    if (this._refreshSubject.observers.length === 1) {
      this.sessionService.refreshToken().subscribe(this._refreshSubject);
    }
    return this._refreshSubject;
  }

  private _checkTokenExpiryErr(error: HttpErrorResponse): boolean {
    return (
      error.status &&
      error.status === STATUS_CODE.UNAUTHORIZED &&
      error.error.message === "TokenExpired"
    );
  }

  intercept(
    req: HttpRequest<any>,
    next: HttpHandler
  ): Observable<HttpEvent<any>> {
    if (req.url.endsWith("/logout") || req.url.endsWith("/token-refresh")) {
      return next.handle(req);
    } else {
      return next.handle(req).pipe(
        catchError((error, caught) => {
          if (error instanceof HttpErrorResponse) {
            if (this._checkTokenExpiryErr(error)) {
              return this._ifTokenExpired().pipe(
                switchMap(() => {
                  return next.handle(this.updateHeader(req));
                })
              );
            } else {
              return throwError(error);
            }
          }
          return caught;
        })
      );
    }
  }

  updateHeader(req) {
    const authToken = this.store.getAccessToken();
    req = req.clone({
      headers: req.headers.set("Authorization", `Bearer ${authToken}`)
    });
    return req;
  }
}

根据@ anton-toshik的评论，我认为在书面形式中解释此代码的功能是个好主意。您可以在我的文章here中阅读有关该代码的解释和理解（它如何工作以及为什么起作用？）。希望对您有所帮助。

Answer 4

Andrei Ostrovski的最终解决方案非常有效，但如果刷新令牌也已过期（假设您正在进行api调用以刷新），则无法正常工作。经过一番挖掘，我意识到刷新令牌API调用也被拦截器截获。我必须添加一个if语句来处理这个问题。

 intercept( request: HttpRequest<any>, next: HttpHandler ):Observable<any> {
   this.authService = this.injector.get( AuthenticationService );
   request = this.addAuthHeader(request);

   return next.handle( request ).catch( error => {
     if ( error.status === 401 ) {

     // The refreshToken api failure is also caught so we need to handle it here
       if (error.url === environment.api_url + '/refresh') {
         this.refreshTokenHasFailed = true;
         this.authService.logout();
         return Observable.throw( error );
       }

       return this.refreshAccessToken()
         .switchMap( () => {
           request = this.addAuthHeader( request );
           return next.handle( request );
         })
         .catch((err) => {
           this.refreshTokenHasFailed = true;
           this.authService.logout();
           return Observable.throw( err );
         });
     }

     return Observable.throw( error );
   });
 }

Answer 5

基于this example，这是我的作品

@Injectable({
    providedIn: 'root'
})
export class AuthInterceptor implements HttpInterceptor {

    constructor(private loginService: LoginService) { }

    /**
     * Intercept request to authorize request with oauth service.
     * @param req original request
     * @param next next
     */
    intercept(req: HttpRequest<any>, next: HttpHandler): Observable<any> {
        const self = this;

        if (self.checkUrl(req)) {
            // Authorization handler observable
            const authHandle = defer(() => {
                // Add authorization to request
                const authorizedReq = req.clone({
                    headers: req.headers.set('Authorization', self.loginService.getAccessToken()
                });
                // Execute
                return next.handle(authorizedReq);
            });

            return authHandle.pipe(
                catchError((requestError, retryRequest) => {
                    if (requestError instanceof HttpErrorResponse && requestError.status === 401) {
                        if (self.loginService.isRememberMe()) {
                            // Authrozation failed, retry if user have `refresh_token` (remember me).
                            return from(self.loginService.refreshToken()).pipe(
                                catchError((refreshTokenError) => {
                                    // Refresh token failed, logout
                                    self.loginService.invalidateSession();
                                    // Emit UserSessionExpiredError
                                    return throwError(new UserSessionExpiredError('refresh_token failed'));
                                }),
                                mergeMap(() => retryRequest)
                            );
                        } else {
                            // Access token failed, logout
                            self.loginService.invalidateSession();
                            // Emit UserSessionExpiredError
                            return throwError(new UserSessionExpiredError('refresh_token failed')); 
                        }
                    } else {
                        // Re-throw response error
                        return throwError(requestError);
                    }
                })
            );
        } else {
            return next.handle(req);
        }
    }

    /**
     * Check if request is required authentication.
     * @param req request
     */
    private checkUrl(req: HttpRequest<any>) {
        // Your logic to check if the request need authorization.
        return true;
    }
}

您可能想要检查用户是否启用Remember Me以使用刷新令牌进行重试，或者只是重定向到注销页面。

Fyi，LoginService有以下方法：
  - getAccessToken（）：string - 返回当前access_token
  - isRememberMe（）：boolean - 检查用户是否有refresh_token
  - refreshToken（）：Observable / Promise - 使用access_token向新的refresh_token请求oauth服务器   - invalidateSession（）：void - 删除所有用户信息并重定向到注销页面

Answer 6

我必须解决以下要求：

• ✅对于多个请求仅刷新一次令牌
• ✅如果refreshToken失败，请注销用户
• ✅如果用户在第一次刷新后出现错误，请注销
• ✅刷新令牌时将所有请求排队

结果，我收集了不同的选项，以刷新Angular中的令牌：

• Brute force solution和tokenRefreshed$ BehaviorSubject作为信号量
• 在catchError的RxJS运算符中使用caught parameter重试请求失败的请求

intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    let retries = 0;
    return this.authService.token$.pipe(
      map(token => req.clone({ setHeaders: { Authorization: `Bearer ${token}` } })),
      concatMap(authReq => next.handle(authReq)),
      // Catch the 401 and handle it by refreshing the token and restarting the chain
      // (where a new subscription to this.auth.token will get the latest token).
      catchError((err, restart) => {
        // If the request is unauthorized, try refreshing the token before restarting.
        if (err.status === 401 && retries === 0) {
          retries++;
    
          return concat(this.authService.refreshToken$, restart);
        }
    
        if (retries > 0) {
          this.authService.logout();
        }
    
        return throwError(err);
      })
    );
}

• 使用retryWhen RxJS operator

intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    return this.authService.token$.pipe(
      map(token => req.clone({ setHeaders: { Authorization: `Bearer ${token}` } })),
      concatMap(authReq => next.handle(authReq)),
      retryWhen((errors: Observable<any>) => errors.pipe(
        mergeMap((error, index) => {
          // any other error than 401 with {error: 'invalid_grant'} should be ignored by this retryWhen
          if (error.status !== 401) {
            return throwError(error);
          }
    
          if (index === 0) {
            // first time execute refresh token logic...
            return this.authService.refreshToken$;
          }
    
          this.authService.logout();
          return throwError(error);
        }),
        take(2)
        // first request should refresh token and retry,
        // if there's still an error the second time is the last time and should navigate to login
      )),
    );
}

所有这些选项都经过严格测试，可以在angular-refresh-token github repo中找到

Answer 7

理想情况下，您希望在发送请求之前检查isTokenExpired。如果过期则刷新令牌并在标头中添加刷新。

除此之外retry operator可能有助于您在401响应中刷新令牌的逻辑。

在您提出请求的服务中使用RxJS retry operator。它接受retryCount参数。 如果没有提供，它将无限期地重试序列。

在你的拦截器上响应刷新令牌并返回错误。当您的服务收回错误但现在正在使用重试操作符，因此它将重试请求，这次使用刷新的令牌（Interceptor使用刷新的令牌添加到标头中。）

import {HttpClient} from '@angular/common/http';
import { Injectable } from '@angular/core';
import { Observable } from 'rxjs/Rx';

@Injectable()
export class YourService {

  constructor(private http: HttpClient) {}

  search(params: any) {
    let tryCount = 0;
    return this.http.post('https://abcdYourApiUrl.com/search', params)
      .retry(2);
  }
}

Answer 8

To support ES6 syntax the solution needs to be bit modify and that is as following also included te loader handler on multiple request


        private refreshTokenInProgress = false;
        private activeRequests = 0;
        private tokenRefreshedSource = new Subject();
        private tokenRefreshed$ = this.tokenRefreshedSource.asObservable();
        private subscribedObservable$: Subscription = new Subscription();



 intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
        if (this.activeRequests === 0) {
            this.loaderService.loadLoader.next(true);
        }
        this.activeRequests++;

        // Handle request
        request = this.addAuthHeader(request);

        // NOTE: if the flag is true it will execute retry auth token mechanism ie. by using refresh token it will fetch new auth token and will retry failed api with new token
        if (environment.retryAuthTokenMechanism) {
            // Handle response
            return next.handle(request).pipe(
                catchError(error => {
                    if (this.authenticationService.refreshShouldHappen(error)) {
                        return this.refreshToken().pipe(
                            switchMap(() => {
                                request = this.addAuthHeader(request);
                                return next.handle(request);
                            }),
                            catchError(() => {
                                this.authenticationService.setInterruptedUrl(this.router.url);
                                this.logout();
                                return EMPTY;
                            })
                        );
                    }

                    return EMPTY;
                }),
                finalize(() => {
                    this.hideLoader();
                })
            );
        } else {
            return next.handle(request).pipe(
                catchError(() => {
                    this.logout();
                    return EMPTY;
                }),
                finalize(() => {
                    this.hideLoader();
                })
            );
        }
    }

    ngOnDestroy(): void {
        this.subscribedObservable$.unsubscribe();
    }

    /**
     * @description Hides loader when all request gets complete
     */
    private hideLoader() {
        this.activeRequests--;
        if (this.activeRequests === 0) {
            this.loaderService.loadLoader.next(false);
        }
    }

    /**
     * @description set new auth token by existing refresh token
     */
    private refreshToken() {
        if (this.refreshTokenInProgress) {
            return new Observable(observer => {
                this.subscribedObservable$.add(
                    this.tokenRefreshed$.subscribe(() => {
                        observer.next();
                        observer.complete();
                    })
                );
            });
        } else {
            this.refreshTokenInProgress = true;

            return this.authenticationService.getNewAccessTokenByRefreshToken().pipe(tap(newAuthToken => {
            this.authenticationService.updateAccessToken(newAuthToken.access_token);
            this.refreshTokenInProgress = false;
            this.tokenRefreshedSource.next();
        }));
        }
    }

    private addAuthHeader(request: HttpRequest<any>) {
        const accessToken = this.authenticationService.getAccessTokenOnly();
        return request.clone({
            setHeaders: {
                Authorization: `Bearer ${accessToken}`
            }
        });
    }

    /**
     * @todo move in common service or auth service once tested
     * logout and redirect to login
     */
    private logout() {
        this.authenticationService.removeSavedUserDetailsAndLogout();
    }

Answer 9

我根据失败请求的url创建了一个新请求，并发送了失败请求的相同主体。

 retryFailedRequests() {

this.auth.cachedRequests.forEach(request => {

  // get failed request body
  var payload = (request as any).payload;

  if (request.method == "POST") {
    this.service.post(request.url, payload).subscribe(
      then => {
        // request ok
      },
      error => {
        // error
      });

  }
  else if (request.method == "PUT") {

    this.service.put(request.url, payload).subscribe(
      then => {
       // request ok
      },
      error => {
        // error
      });
  }

  else if (request.method == "DELETE")

    this.service.delete(request.url, payload).subscribe(
      then => {
        // request ok
      },
      error => {
        // error
      });
});

this.auth.clearFailedRequests();        

}

Answer 10

在authentication.service.ts中，您应该将HttpClient注入为依赖

constructor(private http: HttpClient) { }

然后，您可以重新提交请求（在retryFailedRequests内），如下所示：

this.http.request(request).subscribe((response) => {
    // You need to subscribe to observer in order to "retry" your request
});