我正在尝试实现http-Interceptor,但实际上它不起作用,我也不明白为什么。代码如下,首先进行一些解释:
服务中的http.get无处可去(因此应该出现错误或?这是我要使用Interceptor进行的:记录生产错误。)
我以为算法尝试发送请求,然后拦截器跳入管道,然后点击和/或(?)终结函数处于活动状态,我在控制台上看到了一些东西。但是什么也没发生。
拦截器:
import { HttpInterceptor, HttpRequest, HttpHandler, HttpEvent } from '@angular/common/http';
import { Observable } from 'rxjs';
import { tap, finalize } from 'rxjs/operators';
export class HttpErrorInterceptor implements HttpInterceptor{
intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
console.log("INTERCEPT");
return next.handle(req).pipe(
tap(ev => {
console.log("TAP");
}),
finalize(() => {
console.log("FINALIZE");
})
);
}
}
app.module.ts
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { AppComponent } from './app.component';
import { HttpErrorInterceptor } from './http-error.interceptor';
import { HTTP_INTERCEPTORS, HttpClientModule } from '@angular/common/http';
@NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule,
HttpClientModule
],
providers: [{
provide: HTTP_INTERCEPTORS,
useClass: HttpErrorInterceptor,
multi: true
}],
bootstrap: [AppComponent]
})
export class AppModule { }
test.service.ts
import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';
@Injectable({
providedIn: 'root'
})
export class TestService {
private apiUrl = 'https://localhost:8080/api/users';
constructor(private http: HttpClient) { }
getUsers(): Observable<String[]> {
return this.http.get<String[]>(this.apiUrl)
}
}
和app.component.ts
import { Component } from '@angular/core';
import { TestService } from './test.service';
@Component({
selector: 'app-root',
templateUrl: './app.component.html',
styleUrls: ['./app.component.css']
})
export class AppComponent {
title = 'errorHandling';
constructor(private test: TestService){}
ngOnInit(){
console.log("INIT");
this.test.getUsers();
}
}
答案 0 :(得分:1)
您需要使用TestService getUsers()
方法调用subscribe。否则将无法拨打电话。
更改此行:
this.test.getUsers();
对此:
this.test.getUsers().subscribe();
检查文档here