typescript - fetch api not returning the Location header

Question

Here are my headers copied from chrome Version 52.0.2743.82 (64-bit) (have yet to determine whether this is isolated to chrome)

Request URL:http://localhost:8080/users
Request Method:POST
Status Code:201 
Remote Address:[::1]:8080

Response Headers
view parsed
HTTP/1.1 201
Access-Control-Allow-Origin: http://localhost:9000
Vary: Origin
Access-Control-Allow-Credentials: true
X-Application-Context: application:xenoterracide,development
Location: http://localhost:8080/users/17
X-Content-Type-Options: nosniff
X-XSS-Protection: 1; mode=block
Cache-Control: no-cache, no-store, max-age=0, must-revalidate
Pragma: no-cache
Expires: 0
X-Frame-Options: DENY
Content-Length: 0
Date: Thu, 18 Aug 2016 13:51:19 GMT

Request Headers
view parsed
POST /users HTTP/1.1
Host: localhost:8080
Connection: keep-alive
Content-Length: 92
Pragma: no-cache
Cache-Control: no-cache
accept: application/json
Origin: http://localhost:9000
User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.82 Safari/537.36
content-type: application/json
DNT: 1
Referer: http://localhost:9000/
Accept-Encoding: gzip, deflate
Accept-Language: en-US,en;q=0.8

here's how I'm creating the fetch client

import 'isomorphic-fetch';
import { Router, RouterConfiguration } from 'aurelia-router';
import { Logger } from 'aurelia-logging';
import { Container, LogManager, autoinject } from 'aurelia-framework';
import { Route } from './main/Route';
import { HttpClient } from 'aurelia-fetch-client';

@autoinject
export class App {
router: Router;
private log: Logger = LogManager.getLogger( App );

constructor( container: Container ) {
    let client: HttpClient = new HttpClient;
    client.configure( config => {
        config.useStandardConfiguration()
            .withBaseUrl( 'http://localhost:8080/' )
            .withDefaults( {
                credentials: 'include',
                headers: {
                    Accept: 'application/json'
                }
            } );
    } );
    container.registerSingleton( HttpClient, () => client );
}

this is my service code

@autoinject
export class RegistrationSvc {
private log: Logger = LogManager.getLogger( RegistrationSvc.name );

constructor( private client: HttpClient ) {
}

register( user: RegisterUser ): Promise<any> {
    let basic = user.email + ':' + user.passwordCredentials.password;
    let log = this.log;
    log.debug( `registering ${ basic }` );

    return this.client.fetch( 'users', {
        method: 'post',
        body: json( user )
    } ).then( response => {
        let location = response.headers.get( "Location" );
        log.debug( `location ${ location }` );
    } );

I ran this in chromes's console

response.headers.forEach( v => console.log( v ) );
VM783:1 no-cache
VM783:1 no-cache, no-store, max-age=0, must-revalidate
VM783:1 0
undefined

... where are the rest of my headers? why are they missing?

Answer 1

By default the only headers you will be able to get to in your JavaScript from a fetch response are:

• Cache-Control
• Content-Language
• Content-Type
• Expires
• Last-Modified
• Pragma

To expose others, send a Access-Control-Expose-Headers header in the response, with the value either being an explicit list of just the headers you want to expose, or * to expose them all.