Here is my CanActivate guard clause implementation in TypeScript. However, when I try to compile this code, I encounter the following error:
A function that does not return 'void' or 'any' must have a return value
canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot):boolean {
this.appService.isValidUser().subscribe({
next: (data) => data.authenticated, // will return true or false
error: (err) => false
});
}
What might be causing this error?
Ensure canActivate returns an Observable, rather than a Subscription. Invoking .subscribe() will result in a Subscription, hence the usage of .map().
To manage errors, implement .catch()
canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean> {
return this.appService.checkUserValidity()
.map(data => data.authenticated)
.catch(_ => Observable.of([false]));
}
Remember to import all necessary operators
import 'rxjs/add/observable/of';
import 'rxjs/add/operator/catch';
import 'rxjs/add/operator/map';
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