I'm triggering a HTTP
request and I'm getting a valid response from it. The response also has a header X-Token
that I wish to read. I'm trying the below code to read the headers, however, I get null as a result
this.currentlyExecuting.request = this.http.request(reqParams.type, reqParams.url, {
body: reqParams.body,
responseType: 'json',
observe: 'response'
}).subscribe(
(_response: any) => {
// Also tried _response.headers.init();
const header = _response.headers.get('X-Token');
console.log(header);
onComplete(_response.body);
},
_error => {
onComplete({
code: -1,
message: Constants.WEBSERVICE_INTERNET_NOT_CONNNECTED
});
}
);
The response of the API
, when checked in Chrome inspect, shows the header is present.
This question is related to
angular
http
typescript
angular5
As Hrishikesh Kale has explained we need to pass the Access-Control-Expose-Headers.
Here how we can do it in the WebAPI/MVC environment:
protected void Application_BeginRequest()
{
if (HttpContext.Current.Request.HttpMethod == "OPTIONS")
{
//These headers are handling the "pre-flight" OPTIONS call sent by the browser
HttpContext.Current.Response.AddHeader("Access-Control-Allow-Methods", "GET, POST, OPTIONS");
HttpContext.Current.Response.AddHeader("Access-Control-Allow-Headers", "*");
HttpContext.Current.Response.AddHeader("Access-Control-Allow-Credentials", "true");
HttpContext.Current.Response.AddHeader("Access-Control-Allow-Origin", "http://localhost:4200");
HttpContext.Current.Response.AddHeader("Access-Control-Expose-Headers", "TestHeaderToExpose");
HttpContext.Current.Response.End();
}
}
Another way is we can add code as below in the webApiconfig.cs file.
config.EnableCors(new EnableCorsAttribute("", headers: "", methods: "*",exposedHeaders: "TestHeaderToExpose") { SupportsCredentials = true });
**We can add custom headers in the web.config file as below. *
<httpProtocol>
<customHeaders>
<add name="Access-Control-Expose-Headers" value="TestHeaderToExpose" />
</customHeaders>
</httpProtocol>
we can create an attribute and decore the method with the attribute.
Happy Coding !!
You can get data from post response Headers in this way (Angular 6):
import { HttpClient, HttpHeaders, HttpResponse } from '@angular/common/http';
const httpOptions = {
headers: new HttpHeaders({ 'Content-Type': 'application/json' }),
observe: 'response' as 'response'
};
this.http.post(link,body,httpOptions).subscribe((res: HttpResponse<any>) => {
console.log(res.headers.get('token-key-name'));
})
Angular 7 Service:
this.http.post(environment.urlRest + '/my-operation',body, { headers: headers, observe: 'response'});Component:
this.myService.myfunction().subscribe( (res: HttpResponse) => { console.log(res.headers.get('x-token')); } , error =>{ })
In my case in the POST
response I want to have the authorization header
because I was having the JWT Token
in it.
So what I read from this post is the header I we want should be added as an Expose Header
from the back-end.
So what I did was added the Authorization
header to my Exposed Header like this in my filter class
.
response.addHeader("Access-Control-Expose-Headers", "Authorization");
response.addHeader("Access-Control-Allow-Headers", "Authorization, X-PINGOTHER, Origin, X-Requested-With, Content-Type, Accept, X-Custom-header");
response.addHeader(HEADER_STRING, TOKEN_PREFIX + token); // HEADER_STRING == Authorization
And at my Angular Side
In the Component.
this.authenticationService.login(this.f.email.value, this.f.password.value)
.pipe(first())
.subscribe(
(data: HttpResponse<any>) => {
console.log(data.headers.get('authorization'));
},
error => {
this.loading = false;
});
At my Service Side.
return this.http.post<any>(Constants.BASE_URL + 'login', {username: username, password: password},
{observe: 'response' as 'body'})
.pipe(map(user => {
return user;
}));
You can get headers using below code
let main_headers = {}
this.http.post(url,
{email: this.username, password: this.password},
{'headers' : new HttpHeaders ({'Content-Type' : 'application/json'}), 'responseType': 'text', observe:'response'})
.subscribe(response => {
const keys = response.headers.keys();
let headers = keys.map(key => {
`${key}: ${response.headers.get(key)}`
main_headers[key] = response.headers.get(key)
}
);
});
later we can get the required header form the json object.
header_list['X-Token']
Try this simple code.
1. Components side code: to get both body and header property. Here there's a token in body and Authorization
in the header.
loginUser() {
this.userService.loginTest(this.loginCred).
subscribe(res => {
let output1 = res;
console.log(output1.body.token);
console.log(output1.headers.get('Authorization'));
})
}
2. Service side code: sending login data in the body and observe the response in Observable
any which be subscribed in the component side.
loginTest(loginCred: LoginParams): Observable<any> {
const header1= {'Content-Type':'application/json',};
const body = JSON.stringify(loginCred);
return this.http.post<any>(this.baseURL+'signin',body,{
headers: header1,
observe: 'response',
responseType: 'json'
});
}
You should use the new HttpClient
. You can find more information here.
http
.get<any>('url', {observe: 'response'})
.subscribe(resp => {
console.log(resp.headers.get('X-Token'));
});
Source: Stackoverflow.com