在了解了动态路由的改造原理、方式后，就可以自实现一个小 demo。可以使用 mysql 作为持久化方式，目的是方面、易于管理。
动态路由实战
Zuul Server
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-zuul</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
</dependencies>
spring:
application:
name: spring-cloud-dynamic-route-zuul-server
datasource:
url: jdbc:mysql://localhost:3306/springcloud?useUnicode=true&characterEncoding=utf-8&serverTimezone=Hongkong
driver-class-name: com.mysql.cj.jdbc.Driver
username: root
password: 123456
jpa:
hibernate:
ddl-auto: update
server:
port: 5555
eureka:
instance:
instance-id: ${spring.application.name}:${server.port}
prefer-ip-address: true
client:
service-url:
defaultZone: http://localhost:8761/eureka/
// zuul 路由实体
@Entity
@Table(name = "zuul_route")
@Data
public class ZuulRouteEntity {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;
private String path;
@Column(name = "service_id")
private String serviceId;
private String url;
@Column(name = "strip_prefix")
private boolean stripPrefix = true;
private boolean retryable;
private boolean enabled;
private String description;
}
// dao
public interface ZuulPropertiesDao extends JpaRepository<ZuulRouteEntity, Integer> {
@Query("FROM ZuulRouteEntity WHERE enabled = TRUE")
List<ZuulRouteEntity> findAllByParams();
}
// 动态路由实现
public class DynamicZuulRouteLocator extends SimpleRouteLocator implements RefreshableRouteLocator {
@Autowired
private ZuulProperties zuulProperties;
@Autowired
private ZuulPropertiesDao zuulPropertiesDao;
public DynamicZuulRouteLocator(String servletPath, ZuulProperties properties) {
super(servletPath, properties);
this.zuulProperties = properties;
}
@Override
public void refresh() {
doRefresh();
}
@Override
protected Map<String, ZuulProperties.ZuulRoute> locateRoutes() {
Map<String, ZuulProperties.ZuulRoute> routeMap = new LinkedHashMap<>();
routeMap.putAll(super.locateRoutes());
routeMap.putAll(getProperties());
Map<String, ZuulProperties.ZuulRoute> values = new LinkedHashMap<>();
routeMap.forEach((path, zuulRoute) -> {
path = path.startsWith("/") ? path : "/" + path;
if (StringUtils.hasText(this.zuulProperties.getPrefix())) {
path = this.zuulProperties.getPrefix() + path;
path = path.startsWith("/") ? path : "/" + path;
}
values.put(path, zuulRoute);
});
return values;
}
private Map<String, ZuulProperties.ZuulRoute> getProperties() {
Map<String, ZuulProperties.ZuulRoute> routeMap = new LinkedHashMap<>();
List<ZuulRouteEntity> list = zuulPropertiesDao.findAllByParams();
list.forEach(entity -> {
if (org.apache.commons.lang.StringUtils.isBlank(entity.getPath())) {
return;
}
ZuulProperties.ZuulRoute route = new ZuulProperties.ZuulRoute();
BeanUtils.copyProperties(entity, route);
route.setId(String.valueOf(entity.getId()));
routeMap.put(route.getPath(), route);
});
return routeMap;
}
}
// 注册到 Spring
@Configuration
public class DynamicZuulConfig {
private final ZuulProperties zuulProperties;
private final ServerProperties serverProperties;
@Autowired
public DynamicZuulConfig(ZuulProperties zuulProperties, ServerProperties serverProperties) {
this.zuulProperties = zuulProperties;
this.serverProperties = serverProperties;
}
@Bean
public DynamicZuulRouteLocator dynamicZuulRouteLocator(){
return new DynamicZuulRouteLocator(serverProperties.getServlet().getContextPath(), zuulProperties);
}
}
验证
在数据库中增加三条数据
INSERT INTO `springcloud`.`zuul_route` (`id`, `description`, `enabled`, `path`, `retryable`, `service_id`, `strip_prefix`, `url`) VALUES ('1', '重定向到百度', '\1', '/baidu/**', '\0', NULL, '\1', 'http://www.baidu.com');
INSERT INTO `springcloud`.`zuul_route` (`id`, `description`, `enabled`, `path`, `retryable`, `service_id`, `strip_prefix`, `url`) VALUES ('2', 'url', '\1', '/client/**', '\0', NULL, '\1', 'http://localhost:8081');
INSERT INTO `springcloud`.`zuul_route` (`id`, `description`, `enabled`, `path`, `retryable`, `service_id`, `strip_prefix`, `url`) VALUES ('3', 'serviceId', '\1', '/client-1/**', '\0', 'client-a', '\1', NULL);
访问 http://localhost:5555/baidu/get-result 、http://localhost:5555/client/get-result 、http://localhost:5555/client-a/get-result
重定向百度
this is provider service! this port is: 8081 headers: [user-agent]: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36; [cache-control]: no-cache; [postman-token]: a35929aa-9bcf-f5e4-b79a-0e684b1611ed; [token]: E477CA7B8E7CDCDCE3331742544DE9F1; [content-type]: application/x-www-form-urlencoded;charset=UTF-8; [accept]: */*; [accept-encoding]: gzip, deflate, br; [accept-language]: zh-CN,zh;q=0.9; [x-forwarded-host]: localhost:5555; [x-forwarded-proto]: http; [x-forwarded-prefix]: /client; [x-forwarded-port]: 5555; [x-forwarded-for]: 0:0:0:0:0:0:0:1; [host]: localhost:8081; [connection]: Keep-Alive;
{
"timestamp": "2019-02-21T03:15:18.997+0000",
"status": 404,
"error": "Not Found",
"message": "No message available",
"path": "/client-a/get-result"
}
由此可以证明，动态路由配置成功。
灰度发布
灰度发布是指在系统迭代新功能时的一种平滑过渡的上线发布方式。灰度发布是在原有的系统基础上，额外增加一个新版本，在这个新版本中，有需要验证的功能修改或添加，使用负载均衡器，引入一小部分流量到新版本应用中，如果这个新版本没有出现差错，再平滑地把线上系统或服务一步步替换成新版本，直至全部替换上线结束。
灰度发布实现方式
灰度发布可以使用元数据来实现，元数据有两种
- 标准元数据：标准元数据是服务的各种注册信息，如：ip、端口、健康信息、续约信息等，存储于专门为服务开辟的注册表中，用于其他组件取用以实现整个微服务生态
- 自定义元数据：自定义元数据是使用
eureka.instance.metadata-map.{key}={value}配置，其内部实际上是维护了一个 map 来保存子弹元数据信息，可配置再远端服务，随服务一并注册保存在 Eureka 注册表，对微服务生态没有影响。
灰度发布实战
源码：https://gitee.com/laiyy0728/spring-cloud/tree/master/spring-cloud-zuul/spring-cloud-zuul-metadata
provider
eureka:
client:
service-url:
defaultZone: http://localhost:8761/eureka/
instance:
prefer-ip-address: true
instance-id: ${spring.application.name}:${server.port}
spring:
application:
name: spring-cloud-metadata-provider-service
---
server:
port: 7070
spring:
profiles: node1 # 设定 profile，可以使用 mvn spring-boor:run -Dspring.profiles.active=node1 启动，或者在启动类使用 SpringApplication.run(SpringCloudMetadataProviderServiceApplication.class, "--spring.profiles.active=node1"); 启动
eureka:
instance:
metadata-map:
host-mark: running # 设定当前节点的 metadata，zuul server 使用这个标注来进行路由转发
---
spring:
profiles: node2
server:
port: 7071
eureka:
instance:
metadata-map:
host-mark: running
---
spring:
profiles: node3
server:
port: 7072
eureka:
instance:
metadata-map:
host-mark: gray # 当前节点是灰度节点
@SpringBootApplication
@EnableDiscoveryClient
@RestController
public class SpringCloudMetadataProviderServiceApplication {
public static void main(String[] args) {
SpringApplication.run(SpringCloudMetadataProviderServiceApplication.class, args);
// SpringApplication.run(SpringCloudMetadataProviderServiceApplication.class, "--Dspring.profiles.active=node1"); // 非 maven 启动
}
@Value("${server.port}")
private int port;
@GetMapping(value = "/get-result")
public String getResult(){
return "metadata provider service result, port: " + port;
}
}
Zuul Server
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-zuul</artifactId>
</dependency>
<!-- 实现通过 metadata 进行灰度路由 -->
<dependency>
<groupId>io.jmnarloch</groupId>
<artifactId>ribbon-discovery-filter-spring-cloud-starter</artifactId>
<version>2.1.0</version>
</dependency>
</dependencies>
spring:
application:
name: spring-cloud-metadata-zuul-server
server:
port: 5555
eureka:
instance:
instance-id: ${spring.application.name}:${server.port}
prefer-ip-address: true
client:
service-url:
defautlZone: http://localhost:8761/eureka/
zuul:
routes:
spring-cloud-metadata-provider-service:
path: /provider/**
serviceId: spring-cloud-metadata-provider-service
management:
endpoints:
web:
exposure:
include: '*'
endpoint:
health:
show-details: always
// 实现灰度的 Filter
public class GrayFilter extends ZuulFilter {
@Override
public String filterType() {
return FilterConstants.PRE_TYPE;
}
@Override
public int filterOrder() {
return FilterConstants.PRE_DECORATION_FILTER_ORDER - 1;
}
@Override
public boolean shouldFilter() {
RequestContext context = RequestContext.getCurrentContext();
return !context.containsKey(FilterConstants.FORWARD_TO_KEY) && !context.containsKey(FilterConstants.SERVICE_ID_KEY);
}
@Override
public Object run() throws ZuulException {
HttpServletRequest request = RequestContext.getCurrentContext().getRequest();
String grayMark = request.getHeader("gray_mark");
if (StringUtils.isNotBlank(grayMark) && StringUtils.equals("enable", grayMark)) {
RibbonFilterContextHolder.getCurrentContext().add("host-mark", "gray");
} else {
RibbonFilterContextHolder.getCurrentContext().add("host-mark", "running");
}
return null;
}
}
@SpringBootApplication
@EnableDiscoveryClient
@EnableZuulProxy
public class SpringCloudMetadataZuulServerApplication {
public static void main(String[] args) {
SpringApplication.run(SpringCloudMetadataZuulServerApplication.class, args);
}
@Bean
public GrayFilter grayFilter(){
return new GrayFilter();
}
}
验证
正常访问： http://localhost:5555/provider/get-result ，查看返回值， port 在 7070 和 7071 之间轮询。
gray running
启用 gray_mark header，再次访问，发现 port 始终都是 7072，由此验证灰度成功
gray
