问题描述
我正在尝试在我的应用程序中实现身份验证保护. IE;只有经过身份验证的用户才能访问我的应用的某些路由.我正在此处给出提示.
I'm trying to implement an auth guard in my app. ie; Only authenticated users can access certain routes of my app. I'm following the tut given here.
用户登录后,我将AuthService中的布尔值更改为true,以指示使用已登录.需要在应用程序的整个生命周期中保留该值.
Once the user is logged in I change a boolean value in my AuthService to true to indicate that the use has logged in. Which needs to be retained through out the life of app.
在源代码下方给出:
auth-guard.service.ts
import { Injectable } from '@angular/core';
import {
CanActivate, Router,
ActivatedRouteSnapshot,
RouterStateSnapshot
} from '@angular/router';
import { AuthService } from './auth.service';
@Injectable()
export class AuthGuardService 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 {
console.log('Auth Guard Service: ' + this.authService.isLoggedIn);
if (this.authService.isLoggedIn) { return true; }
// Store the attempted URL for redirecting
this.authService.redirectUrl = url;
// Navigate to the login page with extras
this.router.navigate(['/admin', 'admin-login']);
return false;
}
}
auth.service.ts
import { Injectable } from '@angular/core';
import { Http } from '@angular/http';
import { User } from '../user/shared/user.model';
import { ServiceBase } from '../../core/service.base';
import { appConfig } from '../../core/app.config';
@Injectable()
export class AuthService extends ServiceBase {
public isLoggedIn: boolean = false;
redirectUrl: string;
apiUrl: string;
constructor(private http: Http) {
super();
this.apiUrl = appConfig.apiBaseUrl + '/users/signin';
}
signin(user: User, successCallback, errorCallback) {
return this.http.post(this.apiUrl, user).subscribe(
res => {
this.isLoggedIn = true;
successCallback(res);
},
err => {
//this.isLoggedIn = false;
errorCallback(err);
}
);
}
}
login.component.ts
import { Component, OnInit } from '@angular/core';
import { FormGroup, FormBuilder, FormControl, Validators } from '@angular/forms';
import { Router } from '@angular/router';
import { User } from '../../user/shared/user.model';
import { AuthService } from '../auth.service';
@Component({
moduleId: module.id,
templateUrl: 'login.component.html'
})
export class AdminLoginComponent implements OnInit{
user: User;
userLoginForm: FormGroup;
constructor(
private formBuilder: FormBuilder,
private authService: AuthService,
private router: Router){
this.user = new User();
}
ngOnInit(){
this.buildLoginForm();
}
buildLoginForm() {
...
}
login() {
if(!this.userLoginForm.valid) return false;
this.authService.signin(this.user,
response => {
console.log('Login Component: ' + this.authService.isLoggedIn);
this.router.navigate(['/admin', 'products']);
},
response => {}
);
}
}
控制台输出
XHR finished loading: POST "http://localhost:3000/api/users/signin".
login.component.ts:40 Login Component: true
auth-guard.service.ts:23 Auth Guard Service: false
app.module.ts
import { NgModule } from '@angular/core';
...
import { AuthGuardService } from './auth/auth-guard.service';
import { AuthService } from './auth/auth.service';
@NgModule({
imports: [
...
AdminRoutingModule
],
exports: [
],
declarations: [
...
AdminLoginComponent,
...
],
providers: [
AuthGuardService,
AuthService,
...
],
bootstrap:[]
})
export class AdminModule {}
我在这里做错了什么?任何帮助,将不胜感激.
What am I doing wrong here? Any help would be appreciated.
推荐答案
如ranakrunal9所述,如果您在组件或指令处提供服务,则会为每个此类组件实例获得一个新实例.
As mentioned by ranakrunal9, if you provide a service at a component or directive, you get a new instance for each of such a component instance.
您还为延迟加载的模块(已加载loadChildren
)获得了一个新实例.延迟加载的模块具有自己的根范围,并且如果该延迟加载的模块中提供了服务,则该模块中的组件和服务将获得注入的服务的不同实例.
You also get a new instance for lazy loaded modules (loaded with loadChildren
). Lazy loaded modules get their own root scope and components and services within this module will get a different instance of a service injected if that service is provided within that lazy loaded module.
要确保整个应用程序只有一个实例,请仅在AppModule
或AppModule
直接或间接使用imports: [...]
加载的模块中提供它.
To ensure you only have a single instance for your whole application, provide it only in your AppModule
or a module loaded by AppModule
directly or indirectly using imports: [...]
.
另请参见 https://stackoverflow.com/a/40981772/217408
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