How to get response headers from ajax post request

Question

I want to retrieve response headers sent by server. But i am getting empty object. I can see response headers in chrome dev tools, but can't get them from javascript.

(I am using isomorphic-fetch lib for xhr requests.)

        fetch("http://my.cors.url/postsomedata", {
            method: 'POST',
            headers: {
                Accept: 'application/json',
                'Content-Type': 'application/json',
            },
            body: JSON.stringify(myjsobject),
        })
        .then(response => response.headers)
        .then((headers) => {
            console.log(headers); // empty object
        })

This is not dublicate of How to get Response headers in AJAX I am not using jQuery.

Possible duplicate of [How to get Response headers in AJAX](http://stackoverflow.com/questions/34429628/how-to-get-response-headers-in-ajax) — Yosvel Quintero, Apr 19 '17 at 15:18
If you can't get it from `response.headers`, you can't get it. This smells like a CORS problem. — Kevin B, Apr 19 '17 at 15:19
because those are the dev tools. There's a lot of things in the dev tools that you can't access/do from javascript. — Kevin B, Apr 19 '17 at 15:25
perhaps it is related to this issue? https://github.com/matthew-andrews/isomorphic-fetch/issues/97 — Patrick Hund, Apr 19 '17 at 15:25

score 0 · Accepted Answer · answered Apr 21 '17 at 14:59

The problem was on my back-end server CORS configuration. I am using spring boot, so in order do pass custom headers into xhr response i need to configure spring boot application in following way

@Bean
public WebMvcConfigurer corsConfigurer() {
    return new WebMvcConfigurerAdapter() {
        @Override
        public void addCorsMappings(CorsRegistry registry) {
            registry.addMapping("/**").allowedMethods("GET", "POST", "PUT", "DELETE", "OPTIONS")
                    .exposedHeaders("MyHeader");
        }
    };
}

How to get response headers from ajax post request

1 Answers1