RESTORATION

if pain could talk, what would it say?

// in the same component, or in a separate validator service
customerNumberExistsValidator(): AsyncValidatorFn {
  return (control: AbstractControl): Observable<ValidationErrors | null> => {

    // don't call the API if:
    //  - control is empty
    //  - sync validation already failed (e.g. pattern)
    if (!control.value || control.hasError('pattern')) {
      return of(null);
    }

    return this.customerService.checkCustomerNumber(control.value).pipe(
      map(result => {
        // result should be something like: { exists: boolean }
        return result.exists ? null : { customerNumberNotFound: true };
      }),
      catchError(() => of({ serverError: true })), // optional
      first() // complete the observable
    );
  };
}

Follow me @iamchloediamond on ALL social platforms! 🤳🏼💖

“Only dead fish go with the flow”
“Love many, Trust few, Always paddle your own canoe”

if pain could talk, what would it say?

RØRY