Passing header request header information between services through feign

The problem background

paas When an exception log alarm occurs in the service , Need to be in paas Correspondence in service header Print out the information , Because the interface requests saas service , therefore saas call paas You need to put hearer Pass on the past .

terms of settlement

newly added Feign Configuration class , Realization RequestInterceptor Interface apply Method .

@Slf4j
public class FeignConfig implements RequestInterceptor {

    @Override
    public void apply(RequestTemplate requestTemplate) {
        HttpServletRequest httpServletRequest = this.getHttpServletRequest();
        log.info("RequestTemplate.headers:" + JSON.toJSONString(requestTemplate.headers()));
        if (null != httpServletRequest) {
            Map<String, String> headers = getHeaders(httpServletRequest);
            for (Map.Entry<String, String> entry : headers.entrySet()) {
                requestTemplate.header(entry.getKey(), entry.getValue());
            }
        }
    }

    private HttpServletRequest getHttpServletRequest() {
        try {
            return ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    private Map<String, String> getHeaders(HttpServletRequest request) {
        Map<String, String> map = new LinkedHashMap<>();
        Enumeration<String> enumeration = request.getHeaderNames();
        if (enumeration != null) {
            while (enumeration.hasMoreElements()) {
                String key = enumeration.nextElement();
                String value = request.getHeader(key);
                map.put(key, value);
            }
        }
        return map;
    }
}