实现 ionic 的本机 HTTP 拦截器时出现打字稿错误

Posted 2023-03-13

【中文标题】实现 ionic 的本机 HTTP 拦截器时出现打字稿错误

【英文标题】：Typescript error while implementing ionic's native HTTP interceptor

【发布时间】：2020-12-26 13:49:17

【问题描述】：

当我遇到一些 CORS 问题时，我正在将已经工作的 Angular 10 网络应用程序修改为离子原生应用程序。由于我无法在 BE 上更改任何内容，因此我遇到了 Ionic 的原生 HTTP 插件。

我按照 Angular 在 how to make an interceptor 和这篇解释 how to implement both HttpClient and Ionic's native HTTP 的文章中的说明进行操作，但遇到了新问题。

使用文章中的代码，TS 抱怨这一行：

headers: nativeHttpResponse.headers

(property) headers?: HttpHeaders
Type ' [key: string]: string; ' is missing the following properties from type 'HttpHeaders': headers, normalizedNames, lazyInit, lazyUpdate, and 12 more.ts(2740)
http.d.ts(3406, 9): The expected type comes from property 'headers' which is declared here on type ' body?: any; headers?: HttpHeaders; status?: number; statusText?: string; url?: string; '

这是整个 native-http.interceptor.ts：

import  Injectable  from "@angular/core";
import 
  HttpInterceptor,
  HttpRequest,
  HttpHandler,
  HttpEvent,
  HttpResponse,
 from "@angular/common/http";
import  Observable, from  from "rxjs";
import  Platform  from "@ionic/angular";
import  HTTP  from "@ionic-native/http/ngx";

type HttpMethod =
  | "get"
  | "post"
  | "put"
  | "patch"
  | "head"
  | "delete"
  | "upload"
  | "download";

@Injectable()
export class NativeHttpInterceptor implements HttpInterceptor 
  constructor(private nativeHttp: HTTP, private platform: Platform) 

  public intercept(
    request: HttpRequest<any>,
    next: HttpHandler
  ): Observable<HttpEvent<any>> 
    if (!this.platform.is("cordova")) 
      return next.handle(request);
    

    return from(this.handleNativeRequest(request));
  

  private async handleNativeRequest(
    request: HttpRequest<any>
  ): Promise<HttpResponse<any>> 
    const headerKeys = request.headers.keys();
    const headers = ;

    headerKeys.forEach((key) => 
      headers[key] = request.headers.get(key);
    );

    try 
      await this.platform.ready();

      const method = <HttpMethod>request.method.toLowerCase();

      // console.log(‘— Request url’);
      // console.log(request.url)
      // console.log(‘— Request body’);
      // console.log(request.body);

      const nativeHttpResponse = await this.nativeHttp.sendRequest(
        request.url,
        
          method: method,
          data: request.body,
          headers: headers,
          serializer: "json",
        
      );

      let body;

      try 
        body = JSON.parse(nativeHttpResponse.data);
       catch (error) 
        body =  response: nativeHttpResponse.data ;
      

      const response = new HttpResponse(
        body: body,
        status: nativeHttpResponse.status,
        headers: nativeHttpResponse.headers,  <--------
        url: nativeHttpResponse.url,
      );

      // console.log(‘— Response success’)
      // console.log(response);

      return Promise.resolve(response);
     catch (error) 
      if (!error.status) 
        return Promise.reject(error);
      

      const response = new HttpResponse(
        body: JSON.parse(error.error),
        status: error.status,
        headers: error.headers,
        url: error.url,
      );

      return Promise.reject(response);
    
  

这是我的app.module.ts 的样子：

import  BrowserModule  from '@angular/platform-browser';
import  NgModule  from '@angular/core';
import  RouterModule  from '@angular/router';
import  FormsModule, ReactiveFormsModule  from '@angular/forms';
import  BrowserAnimationsModule  from '@angular/platform-browser/animations';
import  IonicModule  from '@ionic/angular';
import  HTTP  from '@ionic-native/http/ngx';

import  CoreModule  from './core/core.module';
import  SharedModule  from './shared/shared.module';
import  AppComponent  from './app.component';
import  PageNotFoundComponent  from './shared/page-not-found/page-not-found.component';
import  appRoutes  from './app.routes';


@NgModule(
  imports: [
    BrowserModule,
    BrowserAnimationsModule,
    FormsModule,
    ReactiveFormsModule,
    SharedModule,
    CoreModule,
    RouterModule.forRoot(
      appRoutes
    ),
    IonicModule.forRoot()
  ],
  providers: [HTTP],
  declarations: [
    AppComponent,
    PageNotFoundComponent
  ],
  bootstrap: [AppComponent]
)
export class AppModule  

这是我的core.module.ts（我想在其中使用拦截器）的样子：

import  NgModule  from "@angular/core";
import  CommonModule  from "@angular/common";
import  HTTP_INTERCEPTORS, HttpClientModule  from "@angular/common/http";

import  NativeHttpInterceptor  from "./service/native-http.interceptor";
import  AuthService  from "./service/auth.service";
import  ApiService  from "./service/api.service";
import  AuthGuardService  from "./service/auth-guard.service";
import  AuthInterceptor  from "./service/auth-interceptor";
import  WindowRef  from "./service/window-ref-service";

@NgModule(
  imports: [CommonModule, HttpClientModule],
  providers: [
    
      provide: HTTP_INTERCEPTORS,
      useClass: NativeHttpInterceptor,
      multi: true,
    ,
    AuthService,
    ApiService,
    AuthGuardService,
    WindowRef,
    
      provide: HTTP_INTERCEPTORS,
      useClass: AuthInterceptor,
      multi: true,
    ,
  ],
)
export class CoreModule 

【问题讨论】：

这只是一个设计糟糕的API，所以你需要写new HttpResponse( headers: new HttpHeaders(...), ...)。此类 API 的设计者应该受到谴责。

@AluanHaddad 是的，headers: new HttpHeaders(nativeHttpResponse.headers) 通过了 TS 检查。谢谢

【参考方案1】：

Angular 的 HttpRequest 有一个设计笨拙的 API。具体来说，它的构造函数需要 Angular 的 HttpHeaders 的实例，而不是接受标头对象。

因此，在您的情况下，正确的代码是

const response = new HttpResponse(
  body,
  status: nativeHttpResponse.status,
  headers: new HttpHeaders(nativeHttpResponse.headers),
  url: nativeHttpResponse.url
);

我认为这是糟糕的 API 设计简单明了。它偏离了常用的对应API，例如fetch，增加了耦合，并且不是远程惯用的，同时迫使您编写样板。相比之下，Ionic Native 团队采用了正确的方法，将标头指定为对象。