feign 配置使用

简介：feign是springcloud的一个重要组件，主要功能就是服务调用，既可以用于微服务之间调用，也可以rest调用
 

启用

pom文件 添加依赖

  <dependency>
      <groupId>org.springframework.cloudgroupId>
      <artifactId>spring-cloud-starter-openfeignartifactId>
  dependency>

启动类上添加注解 @EnableFeignClients

 

微服务调用

目标：调用微服务里用户服务的获取用户信息接口
步骤：

• 新建一个 interface 接口类
• 注解上填写接口的url
• 方法的写法类似于controller
• 配置 application

IUserService 接口

import com.njc.java.entity.base.ResponseEntity;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;

@FeignClient(value = "user-service", url = "${api.user}")
public interface IUserService {

    @RequestMapping(value = "/user/info", method = RequestMethod.GET)
    ResponseEntity<RespDTO> getUserInfo();

}

application.yml

api:
  user: user-service:8888

rest 调用类似，把 application.yml 修改 url 即可

api:
  user: http://192.168.188.1:8888

 

传参

Header传参

@RequestMapping(value = "/user", method = RequestMethod.GET)
ResponseEntity<RespDTO> userInfo(@RequestHeader(name = "Authorization") String token);

 

URL传参

@RequestMapping(value = "/user/{pernr}", method = RequestMethod.GET)
NjcResponseEntity<UserInfoRespDTO> userInfo( @PathVariable("pernr") String pernr);

 

Params传参

@GetMapping(value = "/user")
NjcResponseEntity<String> userInfo(@SpringQueryMap ReqDTO reqDTO);

 

Body传参

@GetMapping(value = "/user")
NjcResponseEntity<String> userInfo(@RequestBody ReqDTO reqDTO);

 

统一传参

场景举例：IUserService 在调用时，所有接口都需要在 Header 加 token

• 配置 configuration 实现 RequestInterceptor

import feign.RequestInterceptor;
import feign.RequestTemplate;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.http.HttpServletRequest;

public class FeignConfig implements RequestInterceptor {

    @Override
    public void apply(RequestTemplate requestTemplate) {
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        HttpServletRequest request = attributes.getRequest();
        
        //添加token
        requestTemplate.header("Authorization", request.getHeader("Authorization"));
    }
}

• 接口添加 configuration

@FeignClient(url = "${api.user.url}", name = "user-service", configuration = FeignConfig.class)
public interface IUserService {

    @GetMapping(value = "/user/user/{userId}")
    ResponseEntity<UserSimpleInfoRespDTO> getUserInfo(@PathVariable(value = "userId") Long userId);

}

 

日志打印

设置 config

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

@Configuration
public class FeignConfig {

    @Bean
    public Logger.Level feignLogLevel(){
        /* 设置feign客户端的日志打印级别为FULL */
        return Logger.Level.BASIC;
    }

    @Bean
    Logger feignLogger() {
        return new NjcFeignLogger();
    }
}

import cn.hutool.core.io.FileUtil;
import com.alibaba.fastjson.JSON;
import feign.*;
import feign.Response;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import java.io.*;
import java.util.*;
import static feign.Util.decodeOrDefault;
import static java.nio.charset.StandardCharsets.UTF_8;

/**
 * Feign请求日志处理类

 * 所有通过Feign请求的外部接口都会被监控
 */
@Slf4j
public class NjcFeignLogger extends Logger {

    private static final ThreadLocal<Map<String, String>> logContext = new ThreadLocal<>();

    private static final String PATH = "path";

    private static final String METHOD = "method";

    private static final String REQUEST_BODY = "body";

    private static final String HEADER = "header";

    private static final String TIME = "time";

    /**
     * 构建headers字符串
     */
    private String builderHeaders(Map<String, Collection<String>> headersMap) {
        StringBuilder headers = new StringBuilder();
        Iterator<Map.Entry<String, Collection<String>>> iterator = headersMap.entrySet().stream().iterator();
        while (iterator.hasNext()) {
            Map.Entry<String, Collection<String>> next = iterator.next();
            ArrayList<String> values = new ArrayList<>(next.getValue());
            headers.append(next.getKey())
                    .append(":")
                    .append(values.size() == 1 ? values.get(0) : JSON.toJSONString(values))
                    .append(iterator.hasNext() ? "|" : "");
        }
        return headers.toString();
    }

    /**
     * 请求拦截
     */
    @Override
    protected void logRequest(String configKey, Level logLevel, Request request) {
        Map<String, String> map = new HashMap<>(3);
        map.put(PATH, request.url());
        map.put(TIME, System.currentTimeMillis() + "");
        map.put(METHOD, request.httpMethod().name());
        map.put(HEADER, builderHeaders(request.headers()));
        String body = request.body() == null ? null : request.charset() == null ? null : new String(request.body(), request.charset());
        //文件上传不打印请求日志
        if (StringUtils.contains(request.url(), "/helper/common/file/upload")) {
            body = null;
        }
        map.put(REQUEST_BODY, body);
        logContext.set(map);
    }


    /**
     * 响应拦截
     */
    @Override
    protected feign.Response logAndRebufferResponse(
            String configKey, Level logLevel, Response response, long elapsedTime) throws IOException {
        Map<String, String> request = logContext.get();
        logContext.remove();
        // 返回参数
        byte[] bodyData = streamToByteArray(response.body().asInputStream());
        if (null != bodyData && bodyData.length > 0) {
            String responseBody = decodeOrDefault(bodyData, UTF_8, "Binary data");
            log(request, response.status(), responseBody.replaceAll("\\s*|\t|\r|\n", ""));
            return response.toBuilder().body(bodyData).build();
        }
        log(request, response.status(), null);
        return response;
    }

    /**
     * 异常拦截
     */
    @Override
    protected IOException logIOException(String configKey, Level logLevel, IOException ioe, long elapsedTime) {
        Map<String, String> request = logContext.get();
        log.info("Feign-Error -> \npath -> {}\nmethod -> {}\nheaders -> {}\nrequest -> {}\n",
                request.get(PATH), request.get(METHOD), request.get(HEADER), request.get(REQUEST_BODY)
        );
        logContext.remove();
        return ioe;
    }

    /**
     * 日志打印
     *
     * @param request
     * @param responseStatus
     * @param responseBody
     */
    private void log(Map<String, String> request, Integer responseStatus, String responseBody) {
        log.info("\n" +
                        "\npath     -> {}" +
                        "\ntime     -> {}" +
                        "\nmethod   -> {}" +
                        "\nstatus   -> {}" +
                        "\nheaders  -> {}" +
                        "\nrequest  -> {}" +
                        "\nresponse -> {}",
                request.get(PATH),
                (System.currentTimeMillis() - Long.parseLong(request.get(TIME))) + "ms",
                request.get(METHOD),
                responseStatus,
                request.get(HEADER),
                request.get(REQUEST_BODY),
                responseBody
        );
    }

    @Override
    protected void log(String configKey, String format, Object... args) {
        if (log.isInfoEnabled()) {
            log.info(String.format(methodTag(configKey) + format, args));
        }
    }



    /**
     * 输入流转byte[]
     *
     * @param inStream 文件流内容
     * @return
     */
    public static byte[] streamToByteArray(InputStream inStream) {
        if (inStream == null) {
            return null;
        }
        byte[] in2b = null;
        BufferedInputStream in = new BufferedInputStream(inStream);
        ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
        int rc = 0;
        try {
            while ((rc = in.read()) != -1) {
                swapStream.write(rc);
            }
            in2b = swapStream.toByteArray();
        } catch (IOException e) {
            log.warn("streamToByteArray exception inStream:[{}]", inStream, e);
        } finally {
            closeIo(inStream, in, swapStream);
        }
        return in2b;
    }


    /**
     * 关闭流
     */
    public static void closeIo(Closeable... closeable) {
        if (null == closeable || closeable.length <= 0) {
            return;
        }
        for (Closeable cb : closeable) {
            try {
                if (null == cb) {
                    continue;
                }
                cb.close();
            } catch (IOException e) {
                throw new RuntimeException(
                        FileUtil.class.getName(), e);
            }
        }
    }
}

打印结果如下