Question

在 Observable 中调用 Promise

2021-10-21

184

angular typescript firebase angularfire

我想要实现的目标是能够从 getEmployees() 函数异步调用 getToken() 承诺，但不使 getEmployees() 函数异步。

请提供任何想法，并提前致谢。

employee.service

async getToken(): Promise < string > {
  return await this._auth._token();
}

getEmployees(): Observable < EmpleadoTarjeta[] > {

  const promiseSource = from(new Promise(async (resolve) => {
    await this.getToken().then(tokenUser => resolve(tokenUser));
  }));
  let token: any;
  promiseSource.subscribe(tokenPromise => token = tokenPromise);
  const httpHeaders: HttpHeaders = new HttpHeaders({
    tokenJPA: token,
  });

  console.log(token);
  return this._httpClient
    .get<EmpleadoTarjeta[]>('API', { headers: httpHeaders }
    )
    .pipe(
      map(response => response.map(item => new EmpleadoTarjeta(item))),
      tap((empleados) => {
        this._empleados.next(empleados);
      })
    );
}

_auth.service

async _token(): Promise<string> {
    const auth = getAuth();
    return auth.currentUser.getIdTokenResult(true).then(async token => token.token);
}

更新

getEmpleados(): Observable<EmpleadoTarjeta[]> {
 // const token: any = from(this.getToken()).toPromise().then(tokenUser  
=> tokenUser);
const promiseSource: any = from(this.getToken());
const httpHeaders: HttpHeaders = new HttpHeaders({
  tokenJPA: promiseSource.subscribe((tokenPromise: any) => {
    console.log(tokenPromise);
    return tokenPromise;
  }),
});

return this._httpClient
  .get<EmpleadoTarjeta[]>('http://localhost:5001/journeypadel/us-central1/fxManager_Empleados-empleadosRegistrados', { headers: httpHeaders }
  )
  .pipe(
    map(response => response.map(item => new EmpleadoTarjeta(item))),
    tap((empleados) => {
      this._empleados.next(empleados);
    })
  );
}

我按照这种方式做了，但没有成功

Answer 1

您可以将其用作：

const promiseSource = from(this.getToken());

更新

getEmpleados(): Observable<EmpleadoTarjeta[]> {
  return from(this.getToken())
    .pipe(
      map((tokenUser) => new HttpHeaders({
        tokenJPA: tokenUser
      })),
      switchMap((httpHeaders) => this._httpClient
        .get<EmpleadoTarjeta[]>(
          'http://localhost:5001/journeypadel/us-central1/fxManager_Empleados-empleadosRegistrados',
          { headers: httpHeaders }
        )
        .pipe(
          map(response => response.map(item => new EmpleadoTarjeta(item))),
          tap((empleados) => {
            this._empleados.next(empleados);
          })
        ))
    );
}