How to return true value dynamically in AuthGuard?

Question

I have an auth guard with multiple condition and I want to return true value dynamically. How can I do that? Below is my code

auth.guard.ts

canLoad(route: Route, segments: UrlSegment[]): Observable<boolean>|Promise<boolean>|boolean {
    const isSuperAdmin = this.authService.getAuth().role === 'SUPERADMIN';
    const isAdmin = this.authService.getAuth().role === 'ADMIN';
    if (!isAdmin || !isSuperAdmin) {
      this.router.navigate(['/notifications']);
    }
    return true;  //how can I return true dynamically?
}

Answer 1

you can define a boolean variable and change it accordingly:

like this:

    canLoad(route: Route, segments: UrlSegment[]): Observable<boolean>|Promise<boolean>|boolean {

        let dynamicReturn = false;

          const isSuperAdmin = this.authService.getAuth().role === 'SUPERADMIN';
            const isAdmin = this.authService.getAuth().role === 'ADMIN';
            if (!isAdmin || !isSuperAdmin) {

              //change dynamicReturn value accordingly
              dynamicReturn = true
              this.router.navigate(['/notifications']);
            }
            return dynamicReturn ;  //how can I return true dynamically?
        }

Answer 2

I suggest its not [AuthGuard] call it as [AuthorizeGuard] since you are dealing with Application user roles.

you can use something similar like this

import { Injectable } from '@angular/core';
import { CanActivateChild, ActivatedRouteSnapshot, RouterStateSnapshot, UrlTree, Router } from '@angular/router';
import { Observable } from 'rxjs';
import { AuthorizationService } from './authorization.service';
@Injectable({
    providedIn: 'root'
})
export class AuthorizeGuard implements CanActivateChild {


    constructor(private authorizeService: AuthorizationService, private router: Router) {
    }
    canActivateChild(
        route: ActivatedRouteSnapshot,
        state: RouterStateSnapshot): boolean {

        if (this.hasPermissions(route.data.roles)) {
            return true;
        } else {
            this.router.navigate(['/']);
        }
    }

    private hasPermissions(allowedRoles: string[]): boolean {
        const idxArray: number[] = [];
        allowedRoles.forEach((role: string) => {
            const idx: number = this.authorizeService.permissions.indexOf(role);
            if (idx !== -1) {
                idxArray.push(idx);
            }
        });
        if (idxArray.length > 0) {
            return true;
        } else {
            return false;
        }
    }


}

AuthorizationService is using for retrieve login user permissions from API.in my scenario its an Array list.

If login user doesn't have required permission from the array its throw Boolean false.