【SpringBoot】通過Feign調用傳遞Header中參數

如何通過Feign傳遞Header參數

 

問題描述

我們在SpringCloud中使用Feign請求另一個服務的Api接口時，有將Header中參數傳遞下去的需求，如果不做特殊處理，就會將Header中的參數丟失。

 

解決方案

 

方案一：通過 @RequestHeader(name = "headerName") 來傳遞

例如：Feign定義如下

 

@FeignClient(name = "service-name")
public interface XXXFeignClient {
    @RequestMapping(value = "/user/getUserTicket", method = RequestMethod.GET)
    String getUserTicket(@RequestParam("id") String id);
}

 

假設在服務service-name中的/user/getUserTicket接口需要從Header中取Referer數據，那么我們可以將上面代碼進行改造：

@FeignClient(name = "service-name")
public interface XXXFeignClient {
    @RequestMapping(value = "/user/getUserTicket", method = RequestMethod.GET)
    String getUserTicket(@RequestParam("id") String id, @RequestHeader(name = "Referer") String referer);
}

然后在調用的時候將referer參數傳遞進去即可，如

    public String getTicketById(@RequestParam("id") String id, HttpServletRequest request) {
        String referer = request.getHeader("Referer");
        return xxxFeignClient.getUserTicket(id, referer);
    }

 

方案二：通過實現 RequestInterceptor 接口

 首先，自定義實現RequestInterceptor接口的apply方法，如下

import org.springframework.stereotype.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 {
    @Override
    public void apply(RequestTemplate requestTemplate) {
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder
                .getRequestAttributes();
        HttpServletRequest request = attributes.getRequest();
        Enumeration<String> headerNames = request.getHeaderNames();
        if (headerNames != null) {
            while (headerNames.hasMoreElements()) {
                String name = headerNames.nextElement();
                String values = request.getHeader(name);
                requestTemplate.header(name, values);
            }
        }
    }
}

 然后將自定義的配置類配置到Feign中，就可以實現該Feign中接口Header參數的傳遞

    @FeignClient(value = "service-name" ,configuration = FeignConfiguration.class)
    public interface XXXFeignClient {
    }