How to define global static header on Spring Boot Feign Client - spring-boot

Question

I have a spring boot app and want to create a Feign client which has a statically defined header value (for auth, but not basic auth). I found the #Headers annotation but it doesn't seem to work in the realm of Spring Boot. My suspicion is this has something to do with it using the SpringMvcContract.
Here's the code I want to work:
#FeignClient(name = "foo", url = "http://localhost:4444/feign")
#Headers({"myHeader:value"})
public interface LocalhostClient {
But it does not add the headers.
I made a clean spring boot app with my attempts and posted to github here: github example
The only way I was able to make it work was to define the RequestInterceptor as a global bean, but I don't want to do that because it would impact other clients.

Answer 1

You can also achieve this by adding header to individual methods as follows:
#RequestMapping(method = RequestMethod.GET, path = "/resource", headers = {"myHeader=value"})
Using #Headers with dynamic values in Feign client + Spring Cloud (Brixton RC2) discusses a solution for dynamic values using #RequestHeader.

Answer 2

You can set a specific configuration class on your feign interface and define a RequestInterceptor bean in there. For example:
#FeignClient(name = "foo", url = "http://localhost:4444/feign",
configuration = FeignConfiguration.class)
public interface LocalhostClient {
}
#Configuration
public class FeignConfiguration {
#Bean
public RequestInterceptor requestTokenBearerInterceptor() {
return new RequestInterceptor() {
#Override
public void apply(RequestTemplate requestTemplate) {
// Do what you want to do
}
};
}
}

Answer 3

You could specify that through the application.yml file:
feign:
client:
config:
default:
defaultRequestHeaders:
Authorization:
- Basic 3ncond2dS3cr2t
otherHeader:
- value
Note that this will be applicable to all your Feign Clients if it happened that you're using more than one. If that's the case, you could add a section per client instead of adding this to the default section.

Answer 4

Try this
#Component
public class AuthFeignInterceptor implements RequestInterceptor {
#Override
public void apply(RequestTemplate template) {
final RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
if (requestAttributes != null) {
final HttpServletRequest httpServletRequest = ((ServletRequestAttributes) requestAttributes).getRequest();
template.header("Header_name","Value");
}
}
}