[FIXED] Spring boot - corrupt authorization header value after RestTemplate.exchange()

Issue

I'm having a weird problem, i'm using tokens on Microservice enviroment, I need to call another service with the token already generated.

Call to other service on a Client class... There is the method.

return restTemplate.exchange(URL_REST_METHOD,
                HttpMethod.GET,
                httpEntity, //HEADER OK
                SubscriptionDto.class,
                subscriptionId);

To do things easy, I get the previous request, get the token and added to current request.

public class HeaderLoginInterceptor implements ClientHttpRequestInterceptor {

    @Override
    public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
        HttpServletRequest previousRequest = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
        if(previousRequest.getHeader(AUTHORIZATION) != null){
            request.getHeaders().add(AUTHORIZATION, previousRequest.getHeader(AUTHORIZATION));
        }
        return execution.execute(request, body);
    }

}

I attach this interceptor to the Bean RestTemplate

@Bean
public RestTemplate restTemplate() {
    RestTemplate restTemplate = new RestTemplate();

    List<ClientHttpRequestInterceptor> interceptors
            = restTemplate.getInterceptors();
    if (CollectionUtils.isEmpty(interceptors)) {
        interceptors = new ArrayList<>();
    }
    interceptors.add(new HeaderLoginInterceptor());
    restTemplate.setInterceptors(interceptors);
    return restTemplate;
}

The weird thing, after the execution, I see a defect on Authorization header:

Correct one:

---

Bearer  eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzUxMiJ9.eyJhdWQiOiJBZGlkYXMgQ2hhbGxlbmdlIiwic3...

---

Weird after:

Bearer  eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzUxMiJ9.eyJhdWQiOiJBZGlkYXMgQ2hhbGxlbmdlIiwic3...

---

I try adding the token directly before call exchange method, same result.

HttpServletRequest previousRequest = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
HttpHeaders headers = new HttpHeaders();
headers.addAll((MultiValueMap<String, String>) previousRequest.getHeaderNames());
HttpEntity<?> httpEntity = new HttpEntity<>(new HttpHeaders());

---

In both cases, after call method restTemplate.exchange(...) it corrupts.

Any ideas?

Thanks a lot

Solution

After a lot of research, the problem is related to charset of RestTemplate.

If I add this line on @Bean configuration, the problem is solved:

@Bean
public RestTemplate restTemplate() {
    RestTemplate restTemplate = new RestTemplate();
    /*** THE SAVERY LINE ***/
    restTemplate.getMessageConverters().add(0, new StringHttpMessageConverter(Charset.forName("UTF-8")));
    /*** ***/
    List<ClientHttpRequestInterceptor> interceptors
            = restTemplate.getInterceptors();
    if (CollectionUtils.isEmpty(interceptors)) {
        interceptors = new ArrayList<>();
    }
    interceptors.add(new HeaderLoginInterceptor());
    restTemplate.setInterceptors(interceptors);
    return restTemplate;
}

After that, works normally.

Answered By - Ignacio Escursell