Typescript angular guard canactivate

Question

I have some guard on route that looks like this

export class GuardService implements CanActivate {
  constructor(private router: Router, private apiService: InfoService) { }

  canActivate(route: ActivatedRouteSnapshot): Observable<boolean | UrlTree> {
    const { id, type } = route.params;

    if (Object.keys(CustomerType).includes(type)) {
      return this.apiService.get(id).pipe(
        map((overview) => {
          if (type === 'additional') {
            if (overview.main === null) {
              return this.navigate([etc])
            }
            return true;
          }
          return true;
        }),
        catchError(() => false)
      );
    } else {
      return false;
    }
  }
}

The problem is that I have so many conditions, and to many lines, maybe it can be made shorter? Thanks I dont know how to even start

Answer 1

Just reverse your first condition and merge the two as one in the map, it should act as before and be more comprehensible:

export class GuardService implements CanActivate {
    constructor(private router: Router, private apiService: InfoService) { }
  
    canActivate(route: ActivatedRouteSnapshot): Observable<boolean | UrlTree> {
      const { id, type } = route.params;
  
      if (!Object.keys(CustomerType).includes(type)) {
        return false;
      }
      
      return this.apiService.get(id).pipe(
        map((overview) => {
          if (type === 'additional' && overview.main === null) {
              return this.navigate([etc])
            }
            return true;
        }),
        catchError(() => false)
      );
    }
}

Answer 2

You can do it a little bit shorter but nor a huge difference

canActivate(route: ActivatedRouteSnapshot): Observable<boolean | UrlTree> {
    const { id, type } = route.params;

    if (!Object.keys(CustomerType).includes(type)) {
      return false;
    }

    return this.apiService.get(id).pipe(
        map((overview) => {
          if (type === 'additional' && overview.main === null) {
              return this.navigate([etc])
          }
          return true;
        }),
        catchError(() => false)
    );
}