There are two solutions for the feign call header of microservices to be discarded (with source code)

The problem background

In the use of springcloud The micro service feign Invocation time , Will automatically header Throw it away automatically , But basically every service has an overall situation globalId, It can clear the call link , There are two solutions
matters needing attention ：

• You can use the code of the article to create your own project , You can also download the source code for reference

Solution 1

1 It can be used in every remote call , Use @RequestHeader Annotations reseal request headers

    @GetMapping("/mem1")
    String mem1(String res, @RequestHeader String globalId);

Solution 2

1 have access to springcloud Provided feign Interceptor RequestInterceptor, Intercept the request header and reseal

Solution code example

1 feign Interceptor configuration class

package com.lanran.feignheader.config;

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;

/** * @Description: feign Interceptor function ,  solve header Lost problems  * @Created: IDEA2021 * @author:  Blue dye  * @createTime: 2022-07-02 21:10 **/

@Configuration
public class FeignConfig {
    

    @Bean("requestInterceptor")
    public RequestInterceptor requestInterceptor() {
    

        RequestInterceptor requestInterceptor = new RequestInterceptor() {
    
            @Override
            public void apply(RequestTemplate template) {
    
                //1、 Use RequestContextHolder Get the request data just came in 
                ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();

                if (requestAttributes != null) {
    
                    // Old request 
                    HttpServletRequest request = requestAttributes.getRequest();

                    if (request != null) {
    
                        //2、 Synchronization request header data （ Mainly cookie）
                        // Put the old request cookie Put the value on the new request , Make a synchronization 
                        String cookie = request.getHeader("Cookie");
                        template.header("Cookie", cookie);
                    }
                }
            }
        };
        return requestInterceptor;
    }

}

2 Request test interface

package com.lanran.feignheader.controller;

import com.lanran.feignheader.feign.MemFeign;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;

/** * @Author suolong * @Date 2022/7/22 10:58 * @Version 2.0 */
@RestController
public class FeignController {
    

    @Autowired
    MemFeign memFeign;


    @GetMapping("/test1")
    public String test1() {
    
        // Get the request header information of the current thread ( solve Feign Asynchronous call lost request header problem )
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
        // Each thread shares the previous request data 
        RequestContextHolder.setRequestAttributes(requestAttributes);
        String a = memFeign.mem1("a", "dsahjkdhsakj54646");
        System.out.println(a);
        return "success";
    }

    @GetMapping("/test2")
    public String test2() {
    
        // Get the request header information of the current thread ( solve Feign Asynchronous call lost request header problem )
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
        // Before invoking the microservice , Each thread shares the previous request data 
        RequestContextHolder.setRequestAttributes(requestAttributes);
        String a = memFeign.mem2("a");
        System.out.println(a);
        return "success";
    }


}

3 feign call

package com.lanran.feignheader.feign;

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestHeader;

/** * @Author suolong * @Date 2022/7/22 10:59 * @Version 2.0 */
@FeignClient("mem")
public interface MemFeign {
    

    @GetMapping("/mem1")
    String mem1(String res, @RequestHeader String globalId);


    @GetMapping("/mem2")
    String mem2(String res);

}

4 Start class , Turn on feign

package com.lanran.feignheader;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.openfeign.EnableFeignClients;


@EnableFeignClients
@SpringBootApplication
public class FeignHeaderApplication {
    

    public static void main(String[] args) {
    
        SpringApplication.run(FeignHeaderApplication.class, args);
    }

}

5 Dependency import

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.lanran</groupId>
    <artifactId>feignHeader</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>feignHeader</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
            <version>2.2.0.RELEASE</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

6 Example of overall catalog

summary

Before always can't get to the end

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