107. Check for logged in user (#12)

support-portal-frontend/package-lock.json

@@ -371,6 +371,14 @@
       "integrity": "sha512-H71nDOOL8Y7kWRLqf6Sums+01Q5msqBW2KhDUTemh1tvY04eSkSXrK0uj/4mmY0Xr16/3zyZmsrxN7CKuRbNRg==",
       "dev": true
     },
+    "@auth0/angular-jwt": {
+      "version": "5.0.2",
+      "resolved": "https://registry.npmjs.org/@auth0/angular-jwt/-/angular-jwt-5.0.2.tgz",
+      "integrity": "sha512-rSamC9mu+gUxoR86AXcIo+KD7xRIro+/iu1F2Ld85YAZEVKlpB5vYG+g0yGaEOqjtQWP/i0H6fi6XMGPVHSYYQ==",
+      "requires": {
+        "tslib": "^2.0.0"
+      }
+    },
     "@babel/code-frame": {
       "version": "7.14.5",
       "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.14.5.tgz",

support-portal-frontend/package.json

@@ -18,6 +18,7 @@
     "@angular/platform-browser": "~12.2.0",
     "@angular/platform-browser-dynamic": "~12.2.0",
     "@angular/router": "~12.2.0",
+    "@auth0/angular-jwt": "^5.0.2",
     "rxjs": "~6.6.0",
     "tslib": "^2.3.0",
     "zone.js": "~0.11.4"

support-portal-frontend/src/app/service/authentication.service.ts

@@ -4,6 +4,7 @@ import {HttpClient, HttpErrorResponse, HttpResponse} from "@angular/common/http"
 import {UserLogin} from "../dto/user-login";
 import {Observable} from "rxjs";
 import {User} from "../model/user";
+import {JwtHelperService} from "@auth0/angular-jwt";
 
 const USER_STORAGE_KEY = "user";
 const JWT_TOKEN_STORAGE_KEY = "jwt-token";
@@ -18,6 +19,9 @@ export class AuthenticationService {
   private loggedInUser: string | null;
   private storage = localStorage;
 
+  //first install this module: `npm install @auth0/angular-jwt`
+  private jwtHelper: JwtHelperService = new JwtHelperService();
+
   constructor(private httpClient: HttpClient) {
   }
 
@@ -61,4 +65,19 @@ export class AuthenticationService {
     return this.token;
   }
 
+  public isLoggedIn(): boolean {
+    this.loadToken();
+    if (this.token != null && this.token !== '') {
+      let subject = this.jwtHelper.decodeToken(this.token).sub;
+      if (subject != null || '') {
+        if (!this.jwtHelper.isTokenExpired(this.token!)) {
+          this.loggedInUser = subject;
+          return true;
+        }
+      }
+    }
+    this.logout()
+    return false;
+  }
+
 }