我需要在用户登录后为每个后续请求设置一些授权头。
为特定请求设置头信息，
import {Headers} from 'angular2/http';
var headers = new Headers();
headers.append(headerName, value);
// HTTP POST using these headers
this.http.post(url, data, {
headers: headers
})
// do something with the response
参考
但是，以这种方式为每个请求手动设置请求头是不可行的。
我如何设置头设置一旦用户登录，也删除注销这些头?
当前回答
为了回答你的问题，你可以提供一个服务来包装Angular的原始Http对象。如下所述。
import {Injectable} from '@angular/core';
import {Http, Headers} from '@angular/http';
@Injectable()
export class HttpClient {
constructor(private http: Http) {}
createAuthorizationHeader(headers: Headers) {
headers.append('Authorization', 'Basic ' +
btoa('username:password'));
}
get(url) {
let headers = new Headers();
this.createAuthorizationHeader(headers);
return this.http.get(url, {
headers: headers
});
}
post(url, data) {
let headers = new Headers();
this.createAuthorizationHeader(headers);
return this.http.post(url, data, {
headers: headers
});
}
}
而不是注入Http对象，你可以注入这个对象(HttpClient)。
import { HttpClient } from './http-client';
export class MyComponent {
// Notice we inject "our" HttpClient here, naming it Http so it's easier
constructor(http: HttpClient) {
this.http = httpClient;
}
handleSomething() {
this.http.post(url, data).subscribe(result => {
// console.log( result );
});
}
}
我还认为可以通过提供自己的类来扩展Http类，从而为Http类使用多个提供者……请看这个链接:http://blog.thoughtram.io/angular2/2015/11/23/multi-providers-in-angular-2.html。
其他回答
经过一些调查，我发现最后也是最简单的方法是扩展我喜欢的BaseRequestOptions。 以下是我尝试过但由于某些原因放弃的方法: 1. 扩展BaseRequestOptions，并在constructor()中添加动态头。如果我登录，它不能工作。它只创建一次。所以它不是动态的。 2. 扩展Http。与上面的原因相同，我不能在构造函数()中添加动态头文件。如果我重写request(..)方法，并设置报头，像这样:
request(url: string|Request, options?: RequestOptionsArgs): Observable<Response> {
let token = localStorage.getItem(AppConstants.tokenName);
if (typeof url === 'string') { // meaning we have to add the token to the options, not in url
if (!options) {
options = new RequestOptions({});
}
options.headers.set('Authorization', 'token_value');
} else {
url.headers.set('Authorization', 'token_value');
}
return super.request(url, options).catch(this.catchAuthError(this));
}
你只需要重写这个方法，而不是重写所有的get/post/put方法。
3.我的首选解决方案是扩展BaseRequestOptions和覆盖merge():
@Injectable()
export class AuthRequestOptions extends BaseRequestOptions {
merge(options?: RequestOptionsArgs): RequestOptions {
var newOptions = super.merge(options);
let token = localStorage.getItem(AppConstants.tokenName);
newOptions.headers.set(AppConstants.authHeaderName, token);
return newOptions;
}
}
这个merge()函数将被每个请求调用。
为了回答你的问题，你可以提供一个服务来包装Angular的原始Http对象。如下所述。
import {Injectable} from '@angular/core';
import {Http, Headers} from '@angular/http';
@Injectable()
export class HttpClient {
constructor(private http: Http) {}
createAuthorizationHeader(headers: Headers) {
headers.append('Authorization', 'Basic ' +
btoa('username:password'));
}
get(url) {
let headers = new Headers();
this.createAuthorizationHeader(headers);
return this.http.get(url, {
headers: headers
});
}
post(url, data) {
let headers = new Headers();
this.createAuthorizationHeader(headers);
return this.http.post(url, data, {
headers: headers
});
}
}
而不是注入Http对象，你可以注入这个对象(HttpClient)。
import { HttpClient } from './http-client';
export class MyComponent {
// Notice we inject "our" HttpClient here, naming it Http so it's easier
constructor(http: HttpClient) {
this.http = httpClient;
}
handleSomething() {
this.http.post(url, data).subscribe(result => {
// console.log( result );
});
}
}
我还认为可以通过提供自己的类来扩展Http类，从而为Http类使用多个提供者……请看这个链接:http://blog.thoughtram.io/angular2/2015/11/23/multi-providers-in-angular-2.html。
对于Angular 5及以上版本，我们可以使用HttpInterceptor泛化请求和响应操作。 这有助于我们避免重复:
1)通用报头
2)指定响应类型
3)查询请求
import { Injectable } from '@angular/core';
import {
HttpRequest,
HttpHandler,
HttpEvent,
HttpInterceptor,
HttpResponse,
HttpErrorResponse
} from '@angular/common/http';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/do';
@Injectable()
export class AuthHttpInterceptor implements HttpInterceptor {
requestCounter: number = 0;
constructor() {
}
intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
request = request.clone({
responseType: 'json',
setHeaders: {
Authorization: `Bearer token_value`,
'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8'
}
});
return next.handle(request).do((event: HttpEvent<any>) => {
if (event instanceof HttpResponse) {
// do stuff with response if you want
}
}, (err: any) => {
if (err instanceof HttpErrorResponse) {
// do stuff with response error if you want
}
});
}
}
我们可以使用这个AuthHttpInterceptor类作为HttpInterceptors的提供者:
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { AppComponent } from './app.component';
import { AppRoutingModule } from './app.routing-module';
import { AuthHttpInterceptor } from './services/auth-http.interceptor';
import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
@NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule,
AppRoutingModule,
HttpClientModule,
BrowserAnimationsModule,
],
providers: [
{
provide: HTTP_INTERCEPTORS,
useClass: AuthHttpInterceptor,
multi: true
}
],
exports: [],
bootstrap: [AppComponent]
})
export class AppModule {
}
const headers = new HttpHeaders()
.set('content-type', 'application/json')
.set('x-functions-key', '');
return this.http.get<Person[]>(baseUrl, {
headers: headers,
});
使用append方法将新值附加到现有值集
headers.append('Access-Control-Allow-Origin', '*')
虽然我很晚才回，但也许能帮到别人。当使用@NgModule时，要向所有请求注入头文件，可以这样做:
(我在Angular 2.0.1中进行了测试)
/**
* Extending BaseRequestOptions to inject common headers to all requests.
*/
class CustomRequestOptions extends BaseRequestOptions {
constructor() {
super();
this.headers.append('Authorization', 'my-token');
this.headers.append('foo', 'bar');
}
}
现在在@NgModule中执行以下操作:
@NgModule({
declarations: [FooComponent],
imports : [
// Angular modules
BrowserModule,
HttpModule, // This is required
/* other modules */
],
providers : [
{provide: LocationStrategy, useClass: HashLocationStrategy},
// This is the main part. We are telling Angular to provide an instance of
// CustomRequestOptions whenever someone injects RequestOptions
{provide: RequestOptions, useClass: CustomRequestOptions}
],
bootstrap : [AppComponent]
})
