用于 500 个服务器错误的角度句柄

Question

如何修改我的http调用以处理(catch(500服务器错误。我尝试调用 API，但在函数的"err"部分收到"500(内部服务器错误"。如果可能的话，我希望能够抓住它，但不确定如何。有没有简单的方法可以做到这一点？

call_http() {
this.http.get<any>('/api/goes/here').subscribe(data => {
this.result = data;
},
err => {
console.log(err);
});
}

我没有使用任何标头、地图、错误处理程序等。这只是一个基本的调用。

Answer 1

如果要在使用服务进行后端调用时拦截错误HttpClient并且不要在每次调用中重复自己，则需要使用拦截器。

这是我们在应用程序中使用的，根据错误的类型：500、400、404、403，我们重定向、显示支付模式或仅显示 Toast 消息：

HTTP 状态错误代码：

export class HttpError{
static BadRequest = 400;
static Unauthorized = 401;
static Forbidden = 403;
static NotFound = 404;
static TimeOut = 408;
static Conflict = 409;
static InternalServerError = 500;
}

拦截器代码：

import {Injectable, Injector} from '@angular/core';
import {HttpErrorResponse, HttpEvent, HttpHandler, HttpInterceptor, HttpRequest} from '@angular/common/http'
import {Observable} from 'rxjs/Observable';
import {AuthorizationService} from "../authorization.service/authorization.service";
import {HttpError} from "./http-error";
import {Router} from "@angular/router";
import {Toaster} from "nw-style-guide/toasts";
@Injectable()
export class ErrorInterceptor implements HttpInterceptor {
// Regular dep. injection doesn't work in HttpInterceptor due to a framework issue (as of angular@5.2.9),
// use Injector directly (don't forget to add @Injectable() decorator to class).
constructor(private _injector: Injector) {}
intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
const logFormat = 'background: maroon; color: white';
return next.handle(req)
.do(event => {
}, exception => {
if (exception instanceof HttpErrorResponse) {
switch (exception.status) {
case HttpError.BadRequest:
console.error('%c Bad Request 400', logFormat);
break;
case HttpError.Unauthorized:
console.error('%c Unauthorized 401', logFormat);
window.location.href = '/login' + window.location.hash;
break;
case HttpError.NotFound:
//show error toast message
console.error('%c Not Found 404', logFormat);
const _toaster = this._injector.get(Toaster),
_router = this._injector.get(Router);
_toaster.show({
message: exception.error && exception.error.message ? exception.error.message :
exception.statusText,
typeId: 'error',
isDismissable: true
});
_router.navigate(['']);
break;
case HttpError.TimeOut:
// Handled in AnalyticsExceptionHandler
console.error('%c TimeOut 408', logFormat);
break;
case HttpError.Forbidden:
console.error('%c Forbidden 403', logFormat);
const _authService = this._injector.get(AuthorizationService);
_authService.showForbiddenModal();
break;
case HttpError.InternalServerError:
console.error('%c big bad 500', logFormat);
break;
}
}
});
}

}

您还需要将拦截器添加到引导应用的@NgModule提供程序中：

{
provide: HTTP_INTERCEPTORS,
useClass: ErrorInterceptor,
multi: true
},

根据您的需要修改代码 - 启动时 - 我们只是将内容记录到控制台。一旦你有了这个拦截器，它将处理通过HttpClient服务的所有后端请求。

Answer 2

您可以检查错误对象中的 http 状态代码并警告用户或执行其他操作

call_http() {
this.http.get<any>('/api/goes/here').subscribe(data => {
this.result = data;
},
err => {
console.log(err);
// check error status code is 500, if so, do some action
});
}

Answer 3

err => {
if(err.status==500)
console.log(err)
});

}

Answer 4

call_http() {
this.http.get<any>('/api/goes/here').pipe(
map(res => this.result = res),
catchError(err => do something with err)
).subscribe();
}

以上应该允许您捕获错误并执行任何您需要的操作。