An asynchronous method and its corresponding observable returning method

index.ts

getUsers = async () => new Promise((resolve, reject) => {
  if (someCondition) {
    someAsyncOperation()
    .then((result) => resolve(result))
    .catch((err) => reject(err))
  }
  else {
    someOtherAsyncOperation()
    .then((result) => resolve(result))
    .catch((err) => reject(err))
  }
}

getUsers$ = (): Observable<any> => new Observable((observer) => {
  if (someCondition) {
    someAsyncOperation()
    .then((result) => observer.next(result))
    .catch((err) => observer.error(err))
    .finally(() => observer.complete())
  }
  else {
    someOtherAsyncOperation()
    .then((result) => observer.next(result))
    .catch((err) => observer.error(err))
    .finally(() => observer.complete())
  }
}