Angular7 equivalent of C# attribute decorator

user_11675260 0
Viewed 227

I have a api method with an Authorize attribute that checks permissions

[Authorize(ReadIndexes)]
public async Task<IActionResult> GetIndexes ()
{
  ...
}

Is there an equivalent way to decorate a method to check for permissions in Angular so the api call is not carried out if the permissions are not present

##????##
getIndexes(): Observable<Index[]> {
  // dont want to check in the method like below
  if(checkPerms("ReadIndexes")===true){
    ...
  }
}
angular typescript ecmascript-6 javascript c#
2 Answers

There are decorator but you have to write logic for the decorator

Example using decorator is component

@Component({
    selector: "thingy",
    template: `foo`
})
class MyComponent {
}

This is a blog post how you can write custom decorator

user_114871960

Yes you can use the HttpInterceptor in Angular where you can check authorization like 

import {Injectable} from '@angular/core';
import {HttpInterceptor, HttpRequest, HttpHandler, HttpEvent} from '@angular/common/http';
import {Observable, from} from 'rxjs';
import {switchMap} from 'rxjs/operators';

import {AuthService} from './auth.service';


@Injectable()
export class BearerInterceptor implements HttpInterceptor {

  constructor(protected authService: AuthService) {}

  public intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    return from(this.authService.isLoggedIn())
      .pipe(
        switchMap(isLoggedIn => {
          if (isLoggedIn) {
            return this.authService.addTokenToHeader(req.headers)
              .pipe(
                switchMap(headersWithBearer => {
                  const requestWithBearer = req.clone({headers: headersWithBearer});
                  return next.handle(requestWithBearer);
                })
              );
          }

          return next.handle(req);
        })
      );
  }
}
user_13048800
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