auth.service.ts

@Injectable()
export class AuthService {

    private token: string;
    private _user: BehaviorSubject<any>;
    private dataStore;
    user: Observable<any>;
    
    private init() {
        // create observable and subject
        this.dataStore = { user: {}};
        this._user = <BehaviorSubject<any>>new BehaviorSubject({});
        this.user = this._user.asObservable();
        this.setToken(''+this.storage.get('token'));
        this.setUser(this.storage.get('user'));
    }
     
    setUser(user) {
        this.dataStore.user = user;
        this._user.next(Object.assign({}, this.dataStore).user);
        this.storage.set('user', user);
    }

    getUser() {
        return this.dataStore.user;
    }

    logout() {
        this.setUser(undefined);
        this.storage.remove('token');
        this.storage.remove('user');
        this.router.navigate(['login']);
    }

}