[Angular & Web] Retrieve user data from Session

app.route(‘/api/user‘) ?.get(getUser);

import {Request, Response} from ‘express‘;import {sessionStore} from ‘./session-store‘;export function getUser(req: Request, res: Response) { ?// Get sessionid from cookies ?const sessionId = req.cookies[‘SESSIONID‘]; ?// get user according to the session id from the session storage ?const user = sessionStore.findUserBySessionId(sessionId); ?if (user) { ???// if there is user, send successful response ???res.status(200).json(user); ?} else { ???// if there is no user, send empty response ???res.sendStatus(204); ?}}

import {Session} from ‘./session‘;import {User} from ‘../src/app/model/user‘;class SessionStore { ?private sessions: {[key: string]: Session} = {}; ?createSession(sessionId: string, user: User) { ???this.sessions[sessionId] = new Session(sessionId, user); ?} ?findUserBySessionId(sessionId: string): User | undefined { ???const session = this.sessions[sessionId]; ???const isSessionValid = session && session.isValid(); ???return isSessionValid ? session.user : undefined; ?}}// We want only global singletonexport const sessionStore = new SessionStore();

import { Injectable } from ‘@angular/core‘;import {HttpClient} from ‘@angular/common/http‘;import {Observable} from ‘rxjs/Observable‘;import {User} from ‘../model/user‘;import {BehaviorSubject} from ‘rxjs/BehaviorSubject‘;import ‘rxjs/add/operator/map‘;import ‘rxjs/add/operator/shareReplay‘;import ‘rxjs/add/operator/filter‘;import ‘rxjs/add/operator/do‘;export const ANONYMOUS_USER: User = { ?id: undefined, ?email: ‘‘};@Injectable()export class AuthService { ?subject = new BehaviorSubject<User>(undefined); ?// filter out undefined user ?user$: Observable<User> = this.subject.asObservable().filter(user => !!user); ?isLoggedIn$: Observable<boolean> = this.user$.map(user => !!user.id); ?isLoggedOut$: Observable<boolean> = this.isLoggedIn$.map(isLoggedIn => !isLoggedIn); ?constructor(private http: HttpClient) { ???this.http.get<User>(‘/api/user‘) ?????// when there is valid session id, emit the user$ ?????.subscribe((user) => this.subject.next(user ? user : ANONYMOUS_USER)); ?} ?signUp(email: string, password: string) { ???return this.http.post<User>(‘/api/signup‘, { ?????email, ?????password ???}).shareReplay() ?????.do((user) => this.subject.next(user)); ?}}