Feign【开启GIZP压缩】

SpringCloudFeign支持对请求和响应进行gzip压缩，以此来提高通信效率。

1、搭建gzip-demo工程

1.1、工程依赖：

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.RELEASE</version>
        <relativePath/>
</parent>

<properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Finchley.RELEASE</spring-cloud.version>
</properties>

<dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
</dependencyManagement>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!-- Spring Cloud OpenFeign的Starter的依赖 -->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

1.2、工程启动类：

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

@SpringBootApplication
@EnableFeignClients
public class FeignGzipApplication {

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

1.3、编写测试代码：

client接口：

import cn.springcloud.book.feign.config.HelloFeignServiceConfig;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

//https://api.caiyunapp.com/v2/TAkhjf8d1nlSlspN/121.6544,25.1552/forecast.json 彩云天气API
@FeignClient(name = "caiyunapp", url = "https://api.caiyunapp.com/v2/TAkhjf8d1nlSlspN/121.6544,25.1552", configuration = HelloFeignServiceConfig.class)
public interface HelloFeignService {

    @RequestMapping(value = "/forecast.json", method = RequestMethod.GET)
    ResponseEntity<byte[]> searchRepo();

}

config配置类：

import feign.Logger;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class HelloFeignServiceConfig {

    /**
     *
     * Logger.Level 的具体级别如下：
         NONE：不记录任何信息
         BASIC：仅记录请求方法、URL以及响应状态码和执行时间
         HEADERS：除了记录 BASIC级别的信息外，还会记录请求和响应的头信息
         FULL：记录所有请求与响应的明细，包括头信息、请求体、元数据
     * @return
     */
    @Bean
    Logger.Level feignLoggerLevel() {
        return Logger.Level.FULL;
    }

}

controller类：

import cn.springcloud.book.feign.service.HelloFeignService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class HelloFeignController {

    @Autowired
    private HelloFeignService helloFeignService;

    // 服务消费者对位提供的服务
    @GetMapping(value = "/search")
    public ResponseEntity<byte[]> searchGithubRepoByStr() {
        return helloFeignService.searchRepo();
    }

}

1.4、工程配置文件：

server:
  port: 8011
spring:
  application:
    name: ch4-1-gzip

logging:
     level:
       cn.springcloud.book.feign.service.HelloFeignService: debug

feign:
    compression:
        request:
            enabled: true
            mime-types: text/xml,application/xml,application/json # 配置压缩支持的MIME TYPE
            min-request-size: 2048  # 配置压缩数据大小的下限
        response:
            enabled: true # 配置响应GZIP压缩

2、启动工程

访问 http://localhost:8011/search

大功告成！！！

由于开启GZIP压缩之后，Feign之间的调用通过二进制协议进行传输，返回值需要修改为ResponseEntity<byte[]>才可以正常显示，否则会导致服务之间的调用结果乱码。

###提示：

提示1：SpringCloud Finchley.RC2版本中，开启Feign GZIP压缩时，会出现乱码，具体解决方案见：https://github.com/spring-cloud/spring-cloud-openfeign/issues/33

提示2：SpringCloud Finchley.M9版本中，开启Feign GZIP压缩会报错。具体解决方案见：https://github.com/spring-cloud/spring-cloud-openfeign/issues/14