Spring Cloud Zuul的动态路由怎样做？集成Nacos实现很简单
一、说明
网关的核心概念就是路由配置和路由规则，而作为所有请求流量的入口，在实际生产环境中为了保证高可靠和高可用，是尽量要避免重启的，所以实现动态路由是非常有必要的；本文主要介绍实现的思路，并且以Nacos为数据源来讲解
二、实现要点
要实现动态路由只需关注下面4个点
网关启动时，动态路由的数据怎样加载进来
静态路由与动态路由以那个为准，ps：静态路由指的是配置文件里写死的路由配置
监听动态路由的数据源变化
数据有变化时怎样通知zuul刷新路由
三、具体实现
3.1. 实现动态路由的数据加载
重写SimpleRouteLocator类的locateRoutes方法，此方法是加载路由配置的，父类中是获取properties中的路由配置，可以通过扩展此方法，达到动态获取配置的目的
这里采用静态路由与动态路由共存，相同路由id以动态路由优先覆盖的实现方式
AbstractDynRouteLocator类可查看：AbstractDynRouteLocator.java
public abstract class AbstractDynRouteLocator extends SimpleRouteLocator implements RefreshableRouteLocator {
private ZuulProperties properties;
public AbstractDynRouteLocator(String servletPath, ZuulProperties properties) {
super(servletPath, properties);
this.properties = properties;
}
/**
* 刷新路由
*/
@Override
public void refresh() {
doRefresh();
}
@Override
protected Map<String, ZuulRoute> locateRoutes() {
LinkedHashMap<String, ZuulRoute> routesMap = new LinkedHashMap<>();
// 从application.properties中加载静态路由信息
routesMap.putAll(super.locateRoutes());
// 从数据源中加载动态路由信息
routesMap.putAll(loadDynamicRoute());
// 优化一下配置
LinkedHashMap<String, ZuulRoute> values = new LinkedHashMap<>();
for (Map.Entry<String, 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;
}
/**
* 加载路由配置，由子类去实现
*/
public abstract Map<String, ZuulRoute> loadDynamicRoute();}
由于动态路由的数据可以有很多种途径，如：Nacos、Redis、Zookeeper、DB等，所以这里定义一个抽象类，由具体的实现类去定义loadDynamicRoute方法
3.2. Nacos路由实现类
NacosDynRouteLocator类完整的代码实现可查看：NacosDynRouteLocator.java
3.2.1. 实现loadDynamicRoute方法获取动态数据
@Override
public Map<String, ZuulProperties.ZuulRoute> loadDynamicRoute() {
Map<String, ZuulRoute> routes = new LinkedHashMap<>();
if (zuulRouteEntities == null) {
zuulRouteEntities = getNacosConfig();
}
for (ZuulRouteEntity result : zuulRouteEntities) {
if (StrUtil.isBlank(result.getPath()) || !result.isEnabled()) {
continue;
}
ZuulRoute zuulRoute = new ZuulRoute();
BeanUtil.copyProperties(result, zuulRoute);
routes.put(zuulRoute.getPath(), zuulRoute);
}
return routes;
}
private List<ZuulRouteEntity> getNacosConfig() {
try {
String content = nacosConfigProperties.configServiceInstance().getConfig(ZUUL_DATA_ID, ZUUL_GROUP_ID,5000);
return getListByStr(content);
} catch (NacosException e) {
log.error("listenerNacos-error", e);
}
return new ArrayList<>(0);
}3.2.2. 增加NacosListener监听路由数据变化
private void addListener() {
try {
nacosConfigProperties.configServiceInstance().addListener(ZUUL_DATA_ID, ZUUL_GROUP_ID, new Listener() {
@Override
public Executor getExecutor() {
return null;
}
@Override
public void receiveConfigInfo(String configInfo) {
//赋值路由信息
locator.setZuulRouteEntities(getListByStr(configInfo));
RoutesRefreshedEvent routesRefreshedEvent = new RoutesRefreshedEvent(locator);
publisher.publishEvent(routesRefreshedEvent);
}
});
} catch (NacosException e) {
log.error("nacos-addListener-error", e);
}
}注意路由数据变化后不需要自己手动刷新路由，只需要给zuul发送一个RoutesRefreshedEvent事件即可，zuul自己有个ZuulRefreshListener类会监听事件帮我们刷新路由
3.3. 配置类创建NacosDynRouteLocator的Bean
DynamicZuulRouteConfig可查看：NacosDynRouteLocator.java
@Configuration
@ConditionalOnProperty(prefix = "zlt.gateway.dynamicRoute", name = "enabled", havingValue = "true")
public class DynamicZuulRouteConfig {
@Autowired
private ZuulProperties zuulProperties;
@Autowired
private DispatcherServletPath dispatcherServletPath;
/**
* Nacos实现方式
*/
@Configuration
@ConditionalOnProperty(prefix = "zlt.gateway.dynamicRoute", name = "dataType", havingValue = "nacos", matchIfMissing = true)
public class NacosZuulRoute {
@Autowired
private NacosConfigProperties nacosConfigProperties;
@Autowired
private ApplicationEventPublisher publisher;
@Bean
public NacosDynRouteLocator nacosDynRouteLocator() {
return new NacosDynRouteLocator(nacosConfigProperties, publisher, dispatcherServletPath.getPrefix(), zuulProperties);
}
}}
这里通过自定义配置来控制是否开启动态路由功能
3.4. 添加Nacos路由配置
file
新增配置项：
Data Id：zuul-routes
Group：ZUUL_GATEWAY
配置内容：
[
{
"enabled":true,
"id":"csdn",
"path":"/csdn/**",
"retryable":false,
"stripPrefix":true,
"url":"https://www.csdn.net/"
}, {
"enabled":true,
"id":"github",
"path":"/github/**",
"retryable":false,
"stripPrefix":true,
"url":"http://github.com/"
}]
添加两条路由数据
四、测试
启动网关通过/actuator/routes端点查看当前路由信息
file
可以看到静态路由和Nacos里配置的两条路由信息并存显示
修改Nacos配置，关闭csdn路由
file
刷新查看网关的路由信息
file
csdn的路由已经看不到了，实现了动态改变路由配置
原文地址https://www.cnblogs.com/zlt2000/p/11428272.html
