Angular2 canActivate（）调用异步函数

时间：2016-07-17 20:05:18

标签： typescript angular angular2-routing

我正在尝试使用Angular2路由器防护来限制对我的应用中的某些页面的访问。我正在使用Firebase身份验证。为了检查用户是否使用Firebase登录，我必须使用回调调用.subscribe()对象上的FirebaseAuth。这是警卫的代码：

import { CanActivate, Router, ActivatedRouteSnapshot, RouterStateSnapshot } from '@angular/router';
import { AngularFireAuth } from "angularfire2/angularfire2";
import { Injectable } from "@angular/core";
import { Observable } from "rxjs/Rx";

@Injectable()
export class AuthGuard implements CanActivate {

    constructor(private auth: AngularFireAuth, private router: Router) {}

    canActivate(route:ActivatedRouteSnapshot, state:RouterStateSnapshot):Observable<boolean>|boolean {
        this.auth.subscribe((auth) => {
            if (auth) {
                console.log('authenticated');
                return true;
            }
            console.log('not authenticated');
            this.router.navigateByUrl('/login');
            return false;
        });
    }
}

当导航到具有防护功能的页面时，authenticated或not authenticated将打印到控制台（等待来自firebase的响应延迟一段时间后）。但是，导航永远不会完成。此外，如果我没有登录，我将被重定向到/login路由。因此，我遇到的问题是return true没有向用户显示请求的页面。我假设这是因为我正在使用回调，但我无法弄清楚如何做到这一点。有什么想法吗？

9 个答案:

答案 0 :(得分：81)

canActivate需要返回完成的Observable：

@Injectable()
export class AuthGuard implements CanActivate {

    constructor(private auth: AngularFireAuth, private router: Router) {}

    canActivate(route:ActivatedRouteSnapshot, state:RouterStateSnapshot):Observable<boolean>|boolean {
        return this.auth.map((auth) => {
            if (auth) {
                console.log('authenticated');
                return true;
            }
            console.log('not authenticated');
            this.router.navigateByUrl('/login');
            return false;
        }).first(); // this might not be necessary - ensure `first` is imported if you use it
    }
}

缺少return我使用map()代替subscribe()因为subscribe()返回Subscription而不是Observable

答案 1 :(得分：11)

canActivate可以返回Promise来解析boolean

答案 2 :(得分：7)

您可以使用Observable来处理异步逻辑部分。以下是我测试的代码：

import { Injectable } from '@angular/core';
import { CanActivate } from '@angular/router';
import { Observable } from 'rxjs/Observable';
import { DetailService } from './detail.service';

@Injectable()
export class DetailGuard implements CanActivate {

  constructor(
    private detailService: DetailService
  ) {}

  public canActivate(): boolean|Observable<boolean> {
    if (this.detailService.tempData) {
      return true;
    } else {
      console.log('loading...');
      return new Observable<boolean>((observer) => {
        setTimeout(() => {
          console.log('done!');
          this.detailService.tempData = [1, 2, 3];
          observer.next(true);
          observer.complete();
        }, 1000 * 5);
      });
    }
  }
}

答案 3 :(得分：5)

扩展最受欢迎的答案。 AngularFire2的Auth API有所改变。这是实现AngularFire2 AuthGuard的新签名：

import { Injectable } from '@angular/core';
import { Observable } from 'rxjs/Observable';
import { AngularFireAuth } from 'angularfire2/auth';
import { CanActivate, Router, ActivatedRouteSnapshot, RouterStateSnapshot } from '@angular/router';

@Injectable()
export class AuthGuardService implements CanActivate {

  constructor(
    private auth: AngularFireAuth,
    private router : Router
  ) {}

  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot):Observable<boolean>|boolean {
    return this.auth.authState.map(User => {
      return (User) ? true : false;
    });
  }
}

注意：这是一个相当天真的测试。您可以控制日志记录User实例，以查看是否要针对用户的某些更详细的方面进行测试。但至少应该帮助保护路线免受未登录用户的侵害。

答案 4 :(得分：3)

您可以返回true | false作为承诺。

import {Injectable} from '@angular/core';
import {ActivatedRouteSnapshot, CanActivate, Router, RouterStateSnapshot} from '@angular/router';
import {Observable} from 'rxjs';
import {AuthService} from "../services/authorization.service";

@Injectable()
export class AuthGuard implements CanActivate {
  constructor(private router: Router, private authService:AuthService) { }

  canActivate(
    next: ActivatedRouteSnapshot,
    state: RouterStateSnapshot): Observable<boolean> | Promise<boolean> | boolean {
  return new Promise((resolve, reject) => {
  this.authService.getAccessRights().then((response) => {
    let result = <any>response;
    let url = state.url.substr(1,state.url.length);
    if(url == 'getDepartment'){
      if(result.getDepartment){
        resolve(true);
      } else {
        this.router.navigate(['login']);
        resolve(false);
      }
    }

     })
   })
  }
}

答案 5 :(得分：3)

在AngularFire的最新版本中，以下代码有效（与最佳答案有关）。请注意“管道”方法的用法。

import { Injectable } from '@angular/core';
import {ActivatedRouteSnapshot, CanActivate, Router, RouterStateSnapshot} from '@angular/router';
import {AngularFireAuth} from '@angular/fire/auth';
import {map} from 'rxjs/operators';
import {Observable} from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class AuthGuardService implements CanActivate {

  constructor(private afAuth: AngularFireAuth, private router: Router) {
  }

  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean> | Promise<boolean> | boolean {
    return this.afAuth.authState.pipe(
      map(user => {
        if(user) {
          return true;
        } else {
          this.router.navigate(['/login']);
          return false;
        }
      })
    );
  }
}

答案 6 :(得分：2)

就我而言，我需要处理不同的行为取决于响应状态错误。这就是RxJS 6+对我而言的工作方式：

@Injectable()
export class AuthGuard implements CanActivate {

  constructor(private auth: AngularFireAuth, private router: Router) {}

  public canActivate(
    route: ActivatedRouteSnapshot,
    state: RouterStateSnapshot
  ): Observable<boolean> | boolean {
    return this.auth.pipe(
      tap({
        next: val => {
          if (val) {
            console.log(val, 'authenticated');
            return of(true); // or if you want Observable replace true with of(true)
          }
          console.log(val, 'acces denied!');
          return of(false); // or if you want Observable replace true with of(true)
        },
        error: error => {
          let redirectRoute: string;
          if (error.status === 401) {
            redirectRoute = '/error/401';
            this.router.navigateByUrl(redirectRoute);
          } else if (error.status === 403) {
            redirectRoute = '/error/403';
            this.router.navigateByUrl(redirectRoute);
          }
        },
        complete: () => console.log('completed!')
      })
    );
  }
}

在某些情况下，至少在tap operator的next部分，这可能不起作用。删除它并添加旧商品map，如下所示：

  public canActivate(
    route: ActivatedRouteSnapshot,
    state: RouterStateSnapshot
  ): Observable<boolean> | boolean {
    return this.auth.pipe(
      map((auth) => {
        if (auth) {
          console.log('authenticated');
          return true;
        }
        console.log('not authenticated');
        this.router.navigateByUrl('/login');
        return false;
      }),
      tap({
        error: error => {
          let redirectRoute: string;
          if (error.status === 401) {
            redirectRoute = '/error/401';
            this.router.navigateByUrl(redirectRoute);
          } else if (error.status === 403) {
            redirectRoute = '/error/403';
            this.router.navigateByUrl(redirectRoute);
          }
        },
        complete: () => console.log('completed!')
      })
    );
  }

答案 7 :(得分：0)

为了显示另一种实现方式。根据{{​​3}}，并在其他答案中提到，CanActivate的返回类型也可以是解析为布尔值的Promise。

注意：所示示例在Angular 11中实现，但适用于Angular 2+版本。

示例： 

import {
  Injectable
} from '@angular/core';
import {
  ActivatedRouteSnapshot,
  CanActivate,
  CanActivateChild,
  Router,
  RouterStateSnapshot,
  UrlTree
} from '@angular/router';
import {
  Observable
} from 'rxjs/Observable';
import {
  AuthService
} from './auth.service';

@Injectable()
export class AuthGuardService implements CanActivate, CanActivateChild {
  constructor(private authService: AuthService, private router: Router) {}

  canActivate(
    route: ActivatedRouteSnapshot, state: RouterStateSnapshot
  ): Observable < boolean | UrlTree > | Promise < boolean | UrlTree > | boolean | UrlTree {
    return this.checkAuthentication();
  }

  async checkAuthentication(): Promise < boolean > {
    // Implement your authentication in authService
    const isAuthenticate: boolean = await this.authService.isAuthenticated();
    return isAuthenticate;
  }

  canActivateChild(
    childRoute: ActivatedRouteSnapshot, state: RouterStateSnapshot
  ): Observable < boolean | UrlTree > | Promise < boolean | UrlTree > | boolean | UrlTree {
    return this.canActivate(childRoute, state);
  }
}

答案 8 :(得分：0)

<块引用>

使用异步等待...你等待承诺解决

async getCurrentSemester() {
    let boolReturn: boolean = false
    let semester = await this.semesterService.getCurrentSemester().toPromise();
    try {

      if (semester['statusCode'] == 200) {
        boolReturn = true
      } else {
        this.router.navigate(["/error-page"]);
        boolReturn = false
      }
    }
    catch (error) {
      boolReturn = false
      this.router.navigate(["/error-page"]);
    }
    return boolReturn
  }
<块引用>

这是我的授权 (@angular v7.2)

async canActivate(next: ActivatedRouteSnapshot, state: RouterStateSnapshot) {
    let security: any = null
    if (next.data) {
      security = next.data.security
    }
    let bool1 = false;
    let bool2 = false;
    let bool3 = true;

    if (this.webService.getCookie('token') != null && this.webService.getCookie('token') != '') {
      bool1 = true
    }
    else {
      this.webService.setSession("currentUrl", state.url.split('?')[0]);
      this.webService.setSession("applicationId", state.root.queryParams['applicationId']);
      this.webService.setSession("token", state.root.queryParams['token']);
      this.router.navigate(["/initializing"]);
      bool1 = false
    }
    bool2 = this.getRolesSecurity(next)
    if (security && security.semester) {
      // ----  watch this peace of code
      bool3 = await this.getCurrentSemester()
    }

    console.log('bool3: ', bool3);

    return bool1 && bool2 && bool3
  }
<块引用>

路线是

    { path: 'userEvent', component: NpmeUserEvent, canActivate: [AuthGuard], data: {  security: { semester: true } } },
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