ResponseEntityExceptionHandler 为 401 异常返回空响应正文

Question

我正在尝试使用 RestTemplate 实现对身份验证服务器的 Rest 调用，并在服务器返回异常的情况下记录响应。为了做到这一点，我使用了 ResponseEntityExceptionHandler 来处理 HttpClientErrorException 和 HttpServerErrorException。

public Response sendRequest(Request requestBody, String url, HttpMethod httpMethod, Response responseBody) {
    RestTemplate restTemplate = new RestTemplate();
    HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<>(requestBody.getBody(),
            this.securityHeaders);
    ResponseEntity<? extends Response> response = restTemplate.exchange(url, httpMethod, request,
            responseBody.getClass());
    return response.getBody();
}

目前我的 ResponseEntityExceptionHandler 如下

@ControllerAdvice
public class RestResponseExceptionHandler extends ResponseEntityExceptionHandler {

private static Logger log = LoggerFactory.getLogger(RestResponseExceptionHandler.class);
private HttpHeaders headers = new HttpHeaders();

@ExceptionHandler(value = { HttpClientErrorException.class, HttpServerErrorException.class })
protected ResponseEntity<Object> handleConflict(HttpStatusCodeException ex, WebRequest request) {
    ErrorMessage responseBody = new ErrorMessage();
    try {
        JSONObject bodyOfException = new JSONObject(ex.getResponseBodyAsString());
        log.warn("{}| {}", ex.getStatusCode(), bodyOfException);
        responseBody.setErrorAndDescription(bodyOfException.optString("error"),
                bodyOfException.optString("error_description"));
    } catch (JSONException e) {
        log.error("{}| Bad authentication response body | Response Body | {}", ex.getStatusCode(),
                ex.getResponseBodyAsString());
    }

    return handleExceptionInternal(ex, responseBody, headers, ex.getStatusCode(), request);
}

}

但是，仅对于 HttpStatus 401 异常，我得到一个空的响应正文。

日志示例：

400| {"error_description":"Bad client credentials","error":"invalid_client"}

401| Bad authentication response body | Response Body | 

有谁知道我如何获得 401 异常的响应正文？

编辑：当使用邮递员调用身份验证服务器时，我得到非空 401 responseBody：

{
 "error": "invalid_token",
 "error_description": "Token was not recognised"
}

Answer 1

我终于能够记录 401 异常的响应正文。我添加了依赖项

org.apache.httpcomponents:httpclient

并配置了 Rest 模板请求工厂

    restTemplate.setRequestFactory(new HttpComponentsClientHttpRequestFactory());

显然，默认请求工厂 SimpleClientHttpRequestFactory 无法读取 401 Http 状态的响应正文。