How to set respond header values in Spring Boot rest service method?

I was looking for an answer, and I don't like to have to create a response entity. I found the solution on the spring-forums, so credits to the writer.

In short, you can request the response in the method-declaration, so this can be populated.

A simple example:

@RequestMapping(value="/car/{carId}", method = RequestMethod.Get)
@ResponseBody
public Car getCarById(@PathVariable("carId") String Id, HttpServletResponse response) {

    response.setHeader("X-Special-Header", myCar.getEcoLabel());
    //get the car
    return myCar;
}

Hope this helps others as well.

http://forum.spring.io/forum/spring-projects/web-services/102652-setting-header-values-with-spring-rest-controller

To set Response Header there are multiple ways:

1. As mentioned by @Matias Elorriaga, you can use this to add header to single response.
2. Or, To add header to all responses you can also add java Filters.

import java.io.IOException;

import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Component;

@javax.servlet.annotation.WebFilter(urlPatterns = {"/*"})
@Component
public class ResponseHeaderFilter implements javax.servlet.Filter {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletResponse res = (HttpServletResponse) response;
        res.setHeader("My-Custom-Header", "Header-Value-Here");
        chain.doFilter(request, response);
    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    @Override
    public void destroy() {
    }
}

3. Or, In Spring 5, you can also have WebFilter to add headers to all responses.

import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import org.springframework.web.server.WebFilter;
import org.springframework.web.server.WebFilterChain;

@Component
public class ResponseHeaderWebFilter implements WebFilter {

    @Override
    public Mono filter(ServerWebExchange exchange, WebFilterChain chain) {
        exchange.getResponse().getHeaders().add("My-Custom-Header", "My-Value-Here");
        return chain.filter(exchange);
    }
}