场景
A服务
调用B服务
,并且在进入到B服务之前
,设置一个自定义
的hader值
可以传输 B 服务
中的一些内容
到 A 服务中获取
解决
创建FeignConfiguration
import feign.Logger;
import feign.RequestInterceptor;
import feign.RequestTemplate;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.http.HttpServletRequest;
import java.util.Enumeration;
@Configuration
public class FeignConfiguration implements RequestInterceptor {
/**
* 设置header传递,将当前服务的header信息传递到下游服务
*
* @param template
*/
@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 values = request.getHeader(name);
// 跳过 content-length
if ("content-length".equals(name)) {
continue;
}
template.header(name, values);
}
}
template.header("test-header", "123456");
}
}
}
配置@FeignClient,指定配置文件
@FeignClient(value = "b-service",
configuration = {FeignErrorDecoder.class}
)
public interface WageServiceFeign {
......
}
测试
在A服务
的feign配置文件通过template.header("test-header", "123456");
设置了一个header,我们在B服务的Controller中
,测试是否能够获取
还有一点别忘了,在yml文件配置熔断策略,SEMAPHORE,这能保障在一次链路请求中…(其实这里我还也还没搞清楚,后续再聊。。。)
hystrix:
command:
default:
execution:
isolation:
strategy: SEMAPHORE
thread:
timeoutInMilliseconds: 60000