angular - TypeError : You provided an invalid object where a stream was expected. 您可以提供一个 Observable、Promise、Array 或 Iterable

Question

我正在尝试通过服务调用映射，但出现错误。看了subscribe is not defined in angular 2?它说为了订阅我们需要从运营商内部返回。我也有返回声明。

这是我的代码:

checkLogin(): Observable<boolean> {
  return this.service
    .getData()
    .map(
      (response) => {
        this.data = response;
        this.checkservice = true;
        return true;
      },
      (error) => {
        // debugger;
        this.router.navigate(["newpage"]);
        console.log(error);
        return false;
      }
    )
    .catch((e) => {
      return e;
    });
}

错误日志:

TypeError: You provided an invalid object where a stream was expected. You can provide an Observable, Promise, Array, or Iterable

Answer 1

在我的案例中，错误仅发生在端到端测试期间。这是由我的 AuthenticationInterceptor 中的 throwError 引起的。

我从错误的来源导入它，因为我使用了 WebStorm 的导入功能。我正在使用 RxJS 6.2。

错误:

import { throwError } from 'rxjs/internal/observable/throwError';

正确:

import { throwError } from 'rxjs';

这里是拦截器的完整代码:

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

@Injectable()
export class AuthenticationInterceptor implements HttpInterceptor {

  intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    const reqWithCredentials = req.clone({withCredentials: true});
    return next.handle(reqWithCredentials)
     .pipe(
        catchError(error => {
          if (error.status === 401 || error.status === 403) {
            // handle error
          }
          return throwError(error);
        })
     );
  }
}