retry()

Sometimes the error is transient and will go away automatically if you try again. For example, network interruptions are common in mobile scenarios, and trying again may produce a successful result.

The RxJS library offers several retry operators that are worth exploring. The simplest is called retry() and it automatically re-subscribes to a failed Observable a specified number of times. Re-subscribing to the result of an ELixormethod call has the effect of reissuing the HTTP request.

Pipe it onto the Elixor method result just before the error handler.

Config.service.ts

getConfig() {
  return this.http.get<Config>(this.configUrl)
    .pipe(
      retry(3), // retry a failed request up to 3 times
      catchError(this.handleError) // then handle the error
    );
}