spring cloud微服务中多线程下，子线程通过feign调用其它服务，请求头token等丢失

在Spring Cloud微服务架构中，当在多线程环境下，子线程通过Feign客户端调用其他服务时，传递的请求头（例如：token）可能会丢失。这通常是因为默认情况下，Feign的请求作用域是基于线程安全的，但子线程可能没有继承父线程的请求头信息。

为了解决这个问题，你可以使用Feign的配置选项来确保请求头可以在子线程中传递。你可以通过实现Feign.Builder定制器并配置它来实现这一点。以下是一个示例代码：

@Configuration
public class FeignConfig {
 
    @Bean
    public Contract feignContract() {
        return new feign.Contract.Default();
    }
 
    @Bean
    public BasicAuthRequestInterceptor basicAuthRequestInterceptor() {
        return new BasicAuthRequestInterceptor("user", "password");
    }
 
    @Bean
    public feign.Request.Options requestOptions() {
        return new feign.Request.Options(10000, 60000);
    }
 
    @Bean
    public Feign.Builder feignBuilder() {
        return Feign.builder()
                .requestInterceptor(new RequestInterceptor() {
                    @Override
                    public void apply(RequestTemplate template) {
                        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
                        if (attributes != null) {
                            HttpServletRequest request = attributes.getRequest();
                            Enumeration<String> headerNames = request.getHeaderNames();
                            if (headerNames != null) {
                                while (headerNames.hasMoreElements()) {
                                    String name = headerNames.nextElement();
                                    String value = request.getHeader(name);
                                    template.header(name, value);
                                }
                            }
                        }
                    }
                })
                .contract(feignContract())
                .requestInterceptor(new SpringSecurityFeignRequestInterceptor())
                .options(requestOptions());
    }
}
 
public class SpringSecurityFeignRequestInterceptor implements RequestInterceptor {
    @Override
    public void apply(RequestTemplate template) {
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        if (attributes != null) {
            HttpServletRequest request = attributes.getRequest();
            Enumeration<String> headerNames = re