每次调用Angular Service时都会重置 [英] Angular Service is reset on each call of it

问题描述

在我的Web Angular项目中，我创建了AuthenticationGuard和AuthenticationService来处理安全性.

In my web Angular project I've created an AuthenticationGuard and an AuthenticationService to handle the security.

这些文件来自我项目的另一个分支，它们工作正常.

These files comes from another branch of my project who works perfectly.

这是我的脚本的工作方式:

Here is how my scripts should works:

1. 导航到身份验证/登录"
2. 用户输入其凭据
3. Authservice调用后端wepApi以获取Bearer令牌
4. 后端返回令牌.
5. AuthService将他的var'isLoggedIn'设置为true；
6. AuthService用于路由以导航到"/home"
7. AuthGuard通过检查AuthService的"isLoggedIn"来检查身份验证.

我的问题是当AuthGuard访问AuthService时:AuthService总是返回false.

My problem is when AuthGuard access the AuthService : AuthService always return false.

auth.guard.ts

auth.guard.ts

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

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

  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): boolean {
    let url: string = state.url;

    return this.checkLogin(url);
  }

  checkLogin(url: string): boolean {
    if (this.authService.getIsLoggedIn()) { 
      return true; 
    }

    // Store the attempted URL for redirecting
    this.authService.redirectUrl = url;

    // Navigate to the login page with extras
    this.router.navigate(['/auth/login']);
    return false;
  }
}

auth.service.ts

auth.service.ts

import { Injectable } from '@angular/core';
import { Router } from '@angular/router';

import { Observable } from 'rxjs/Observable';
import 'rxjs/add/observable/of';
import 'rxjs/add/operator/do';
import 'rxjs/add/operator/delay';

import { config } from './../shared/smartadmin.config';

import { Http, Headers, RequestOptions, Response } from '@angular/http';
import 'rxjs/add/operator/map'

@Injectable()
export class AuthService {
    private isLoggedIn: boolean = false;

    public redirectUrl: string;

    constructor(private router: Router, private http: Http) {
    }

    public getIsLoggedIn(): boolean {
        console.log("getIsLoggedIn() = " + this.isLoggedIn); // Always returns false
        return this.isLoggedIn;
    }

    public login(username: string, password: string) {
        this.ProcessLogin(username, password)
            .subscribe(result => {
                if (result === true) {
                    console.log("before attribution");
                    console.log("this.isLoggedIn = " + this.isLoggedIn); // returns false
                    this.isLoggedIn = true;
                    console.log("after attribution");
                    console.log("this.isLoggedIn = " + this.isLoggedIn); // returns true
                    this.router.navigate(this.redirectUrl ? [this.redirectUrl] : ['/home']);
                } else {
                    this.logout();
                }
            });
    }


    public logout(): void {
        localStorage.removeItem('oAuthToken');
        this.isLoggedIn = false;
    }

    private ProcessLogin(username: string, password: string): Observable<boolean> {

        let headers = new Headers({ 'Content-Type': 'application/x-www-form-urlencoded' });
        let options = new RequestOptions({ headers: headers });
        let body = 'grant_type=password&username=' + encodeURIComponent(username) + '&password=' + encodeURIComponent(password);

        let endpoint = config.API_ENDPOINT + 'token';

        return this.http.post(endpoint, body, options)
            .map((response: Response) => {
                // login successful if there's a jwt token in the response
                let token = response.json() && response.json().access_token;
                if (token) {
                    localStorage.setItem('oAuthToken', token);

                    // return true to indicate successful login
                    return true;
                } else {
                    localStorage.removeItem('oAuthToken');
                    // return false to indicate failed login
                    return false;
                }
            });
    }
}

推荐答案

我没有看到您的模块定义，我怀疑您没有将AuthService用作核心服务(单例)，这意味着使用它的每个模块都将具有它自己的实例(跟踪自己的isLoggedIn标志).

Without having seen your module definitions I suspect that you have not made AuthService a core service (a Singleton) which mean that every module that makes use of it will have its own instance (keeping track of its own isLoggedIn flag).

要使服务单角度地进行，必须由根模块注入器提供服务.为此，您将需要执行以下操作:

To make a service a singleton in angular it has to be served by the root module injector. To accomplish this you will need to do this:

import { NgModulep } from '@angular/core';
import { CommonModule, ModuleWithProviders } from '@angular/common';
import { AuthService, AuthGuard } from './services/index';

@NgModule({
  imports: [
    CommonModule,
    ModuleWithProviders
  ]
})
export class SharedModule {

  static forRoot(): ModuleWithProviders {
    return {
      ngModule: SharedModule,
      providers: [
        AuthService,
        AuthGuard
      ]
    };
  }

}

然后在将SharedModule导入根AppModule时调用forRoot方法.

And then call the forRoot method when importing the SharedModule into the root AppModule.

@NgModule({
  imports: [
    ...
    SharedModule.forRoot(),
    ...
  ],
  ...,
  bootstrap: [AppComponent]
})
export class AppModule { }

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