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Spring-Cloud-网关服务-zuul-三-动态路由

jiezi

zuul 动态路由

网关服务是流量的唯一入口。不能随便停服务。所以动态路由就显得尤为必要。

数据库动态路由基于事件刷新机制热修改 zuul 的路由属性。

DiscoveryClientRouteLocator

可以看到 DiscoveryClientRouteLocator 是默认的刷新的核心处理类。


// 重新加载路由信息方法 protected 方法。需要子方法重新方法。protected LinkedHashMap<String, ZuulRoute> locateRoutes() 

// 触发刷新的方法  RefreshableRouteLocator 接口
 public void refresh() {this.doRefresh();
    }

而这俩个方法都是继承与 SimpleRouteLocator 类，并进行了重新操作。其实官方的方法注释说明了。如果需要动态读取加载映射关系。则需要子类重写这俩个方法。
进行具体的实现

首先 pom jar 包导入 需要连接 mysql 数据库 

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <!-- jdbc -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

路由实体 ZuulRouteEntity

package com.xian.cloud.entity;

import lombok.Data;

import java.io.Serializable;
import java.util.Date;

/**
 * <Description> 路由实体类
 *
 * @author xianliru@100tal.com
 * @version 1.0
 * @createDate 2019/10/30 15:00
 */
@Data
public class ZuulRouteEntity implements Serializable {
    private static final long serialVersionUID = 1L;

    /**
     * router Id
     */
    private Integer id;
    /**
     * 路由路径
     */
    private String path;
    /**
     * 服务名称
     */
    private String serviceId;
    /**
     * url 代理
     */
    private String url;
    /**
     * 转发去掉前缀
     */
    private String stripPrefix;
    /**
     * 是否重试
     */
    private String retryable;
    /**
     * 是否启用
     */
    private String enabled;
    /**
     * 敏感请求头
     */
    private String sensitiveheadersList;
    /**
     * 创建时间
     */
    private Date createTime;
    /**
     * 更新时间
     */
    private Date updateTime;
    /**
     * 删除标识（0- 正常,1- 删除）*/
    private String delFlag;
}

新建 DiscoveryRouteLocator 类 父类 接口 都不变化 


package com.xian.cloud.router;


import com.google.common.base.Strings;
import com.google.common.collect.Sets;
import com.xian.cloud.entity.ZuulRoute;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.netflix.zuul.filters.RefreshableRouteLocator;
import org.springframework.cloud.netflix.zuul.filters.SimpleRouteLocator;
import org.springframework.cloud.netflix.zuul.filters.ZuulProperties;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.util.StringUtils;

import java.util.*;

/**
 * <Description>
 *
 * @author xianliru@100tal.com
 * @version 1.0
 * @createDate 2019/10/30 18:57
 */
@Slf4j
public class DiscoveryRouteLocator extends SimpleRouteLocator implements RefreshableRouteLocator {

    private ZuulProperties properties;

    private JdbcTemplate jdbcTemplate;

    public DiscoveryRouteLocator(String servletPath, ZuulProperties properties, JdbcTemplate jdbcTemplate) {super(servletPath, properties);
        this.properties = properties;
        this.jdbcTemplate = jdbcTemplate;
        log.info("servletPath:{}",servletPath);
    }

    @Override
    public void refresh() {doRefresh();
    }

    @Override
    protected Map<String, ZuulProperties.ZuulRoute> locateRoutes() {LinkedHashMap<String, ZuulProperties.ZuulRoute> routesMap = new LinkedHashMap<String, ZuulProperties.ZuulRoute>();
        // 从配置文件中加载路由信息
        routesMap.putAll(super.locateRoutes());
        // 自定义加载路由信息
        routesMap.putAll(getRouteList());
        // 优化一下配置
        LinkedHashMap<String, ZuulProperties.ZuulRoute> values = new LinkedHashMap<>();
        for (Map.Entry<String, ZuulProperties.ZuulRoute> entry : routesMap.entrySet()) {String path = entry.getKey();
            // Prepend with slash if not already present.
            if (!path.startsWith("/")) {path = "/" + path;}
            if (StringUtils.hasText(this.properties.getPrefix())) {path = this.properties.getPrefix() + path;
                if (!path.startsWith("/")) {path = "/" + path;}
            }
            values.put(path, entry.getValue());
        }
        return values;
    }

    /**
     * 从数据库读取 zuul 路由规则
     * @return
     */
   private LinkedHashMap<String, ZuulProperties.ZuulRoute> getRouteList() {LinkedHashMap<String, ZuulProperties.ZuulRoute> zuulRoutes = new LinkedHashMap<>();
        List<ZuulRoute> sysZuulRoutes = jdbcTemplate.query("select * from sys_zuul_route where del_flag = 0", new BeanPropertyRowMapper<>(ZuulRoute.class));

       for (ZuulRoute route: sysZuulRoutes) {

           // 为空跳过
           if (Strings.isNullOrEmpty(route.getPath()) && Strings.isNullOrEmpty(route.getUrl())) {continue;}

           ZuulProperties.ZuulRoute zuulRoute = new ZuulProperties.ZuulRoute();
           try {zuulRoute.setId(route.getServiceId());
               zuulRoute.setPath(route.getPath());
               zuulRoute.setServiceId(route.getServiceId());
               zuulRoute.setRetryable(Objects.equals("0", route.getRetryable()) ? Boolean.FALSE : Boolean.TRUE);
               zuulRoute.setStripPrefix(Objects.equals("0", route.getStripPrefix()) ? Boolean.FALSE : Boolean.TRUE);
               zuulRoute.setUrl(route.getUrl());
               List<String> sensitiveHeadersList = Arrays.asList(route.getSensitiveheadersList().split(","));
               if (sensitiveHeadersList != null) {Set<String> sensitiveHeaderSet = Sets.newHashSet();
                   sensitiveHeadersList.forEach(sensitiveHeader -> sensitiveHeaderSet.add(sensitiveHeader));
                   zuulRoute.setSensitiveHeaders(sensitiveHeaderSet);
                   zuulRoute.setCustomSensitiveHeaders(true);
               }
           } catch (Exception e) {log.error("数据库加载配置异常", e);
           }
           log.info("自定义的路由配置,path：{}，serviceId:{}", zuulRoute.getPath(), zuulRoute.getServiceId());
           zuulRoutes.put(zuulRoute.getPath(), zuulRoute);

       }
        return zuulRoutes;
   }
}

我们还需要一个事件的生产者 和 消费者 直接图方便 集成到一个类中 

package com.xian.cloud.event;

import com.xian.cloud.router.DiscoveryRouteLocator;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.discovery.event.HeartbeatEvent;
import org.springframework.cloud.client.discovery.event.HeartbeatMonitor;
import org.springframework.cloud.context.scope.refresh.RefreshScopeRefreshedEvent;
import org.springframework.cloud.netflix.zuul.RoutesRefreshedEvent;
import org.springframework.cloud.netflix.zuul.web.ZuulHandlerMapping;
import org.springframework.context.ApplicationEvent;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.ApplicationListener;
import org.springframework.context.event.ContextRefreshedEvent;
import org.springframework.stereotype.Service;

/**
 * <Description> 路由刷新事件发布，与事件监听者
 *
 * @author xianliru@100tal.com
 * @version 1.0
 * @createDate 2019/10/30 15:27
 */
@Service
public class RefreshRouteService implements ApplicationListener<ApplicationEvent> {

    @Autowired
    private ZuulHandlerMapping zuulHandlerMapping;

    private HeartbeatMonitor heartbeatMonitor = new HeartbeatMonitor();

    @Autowired
    ApplicationEventPublisher publisher;

    @Autowired
    private DiscoveryRouteLocator dynamicRouteLocator;

    /**
     * 动态路由实现 调用 refreshRoute() 发布刷新路由事件
     */
    public void refreshRoute() {RoutesRefreshedEvent routesRefreshedEvent = new RoutesRefreshedEvent(dynamicRouteLocator);
        publisher.publishEvent(routesRefreshedEvent);
    }

    /**
     * 事件监听者。监控检测事件刷新
     * @param event
     */
    @Override
    public void onApplicationEvent(ApplicationEvent event) {if(event instanceof ContextRefreshedEvent || event instanceof RefreshScopeRefreshedEvent || event instanceof RoutesRefreshedEvent){
            // 主动手动刷新。上下文刷新，配置属性刷新
            zuulHandlerMapping.setDirty(true);
        }else if(event instanceof HeartbeatEvent){
            // 心跳触发，将本地映射关系。关联到远程服务上
            HeartbeatEvent heartbeatEvent = (HeartbeatEvent)event;
            if(heartbeatMonitor.update(heartbeatEvent.getValue())){zuulHandlerMapping.setDirty(true);
            }
        }
    }
}

对外提供触发接口 

package com.xian.cloud.controller;

import com.xian.cloud.event.RefreshRouteService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * <Description> 手动刷新对外接口
 *
 * @author xianliru@100tal.com
 * @version 1.0
 * @createDate 2019/10/30 20:23
 */
@RestController
public class RefreshController {

    @Autowired
    private RefreshRouteService refreshRouteService;

    @GetMapping("/refresh")
    public String refresh() {refreshRouteService.refreshRoute();
        return "refresh";
    }

}

数据库表结构 

CREATE TABLE `sys_zuul_route` (`id` int(11) NOT NULL AUTO_INCREMENT COMMENT 'router Id',
  `path` varchar(255) NOT NULL COMMENT '路由路径',
  `service_id` varchar(255) NOT NULL COMMENT '服务名称',
  `url` varchar(255) DEFAULT NULL COMMENT 'url 代理',
  `strip_prefix` char(1) DEFAULT '1' COMMENT '转发去掉前缀',
  `retryable` char(1) DEFAULT '1' COMMENT '是否重试',
  `enabled` char(1) DEFAULT '1' COMMENT '是否启用',
  `sensitiveHeaders_list` varchar(255) DEFAULT NULL COMMENT '敏感请求头',
  `create_time` timestamp NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
  `update_time` timestamp NULL DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
  `del_flag` char(1) DEFAULT '0' COMMENT '删除标识（0- 正常,1- 删除）',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=utf8mb4 ROW_FORMAT=DYNAMIC COMMENT='动态路由配置表'

将配置文件 client 消费者服务 路由配置注释掉。设置数据源。从数据库中读取

启动服务打印日志 

2019-10-30 20:49:39.946  INFO 63449 --- [TaskScheduler-1] c.xian.cloud.router.DynamicRouteLocator  : 添加数据库自定义的路由配置,path：/client/**，serviceId:cloud-discovery-client
2019-10-30 20:49:40.397  INFO 63449 --- [TaskScheduler-1] c.xian.cloud.router.DynamicRouteLocator  : 添加数据库自定义的路由配置,path：/client/**，serviceId:cloud-discovery-client

postman 请求 client 接口 看看是否能转发成功

基于 zuul 动态网关路由完成。

后续还会更新网关的灰度方案、swagger2 整合的调试源服务。敬请期待！

摘自参考 spring cloud 官方文档

参考书籍 重新定义 spring cloud 实战

示例代码地址

服务器 nacos 地址 http://47.99.209.72:8848/nacos

往期地址 spring cloud alibaba 地址

spring cloud alibaba 简介

Spring Cloud Alibaba (nacos 注册中心搭建)

Spring Cloud Alibaba 使用 nacos 注册中心

Spring Cloud Alibaba nacos 配置中心使用

spring cloud 网关服务

Spring Cloud zuul 网关服务 一

Spring Cloud 网关服务 zuul 二

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