上节我们在springcloud Alibaba 入门之采用Sentinel实现接口限流文章中简单知道了sentinel其中的一个作用,我们这里只用它来做限流的操作,但是有个问题不知道大家知道不,当我们将sentinel控制台重启之后,我们自己定义的限流规则会丢失,那么本篇
博客就是为了解决该问题而写的,全程采用的都是本地服务,大致分为了两步走:
- 一是修改sentinel Dashboard的规则然后进行同步到nacos中
- 二是在nacos管理台对我们限流的规则进行自定义的过程
首先我们来看修改sentinel Dashboard的规则,我们需要fork sentinel的源码在其基础上修改,fork 源码的地址为:Sentinel源码地址,具体的步骤如下:
- a.首先我们来修改pom.xml中的sentinel-datasource-nacos的依赖,将<scope>test</scope>注释掉,这样做的目的是为了在我们的主程序中起到作用,代码如下:
<!-- for Nacos rule publisher sample -->
<dependency>
<groupId>com.alibaba.csp</groupId>
<artifactId>sentinel-datasource-nacos</artifactId>
<scope>test</scope>
</dependency>
- b.接着我们需要修改resources/app/scripts/directives/sidebar/sidebar.html页面中的一段代码如:
<li ui-sref-active="active" ng-if="!entry.isGateway">
<a ui-sref="dashboard.flowV1({app: entry.app})">
<i class="glyphicon glyphicon-filter"></i> 流控规则</a>
</li>
修改之后为:
<li ui-sref-active="active">
<a ui-sref="dashboard.flow({app: entry.app})">
<i class="glyphicon glyphicon-filter"></i> 流控规则
</a>
</li>
- c.在com.alibaba.csp.sentinel.dashboard.rule包下新建一个nacos包,该包下主要存放我们对nacos的拓展规则以及配置的书写.
- d.在nacos包下创建Nacos的配置类,代码如下:
''''
package com.alibaba.csp.sentinel.dashboard.rule.nacos;
import com.alibaba.csp.sentinel.dashboard.datasource.entity.rule.FlowRuleEntity;
import com.alibaba.csp.sentinel.datasource.Converter;
import com.alibaba.fastjson.JSON;
import com.alibaba.nacos.api.PropertyKeyConst;
import com.alibaba.nacos.api.config.ConfigFactory;
import com.alibaba.nacos.api.config.ConfigService;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.util.List;
import java.util.Properties;
/**
* @author cb
*/
@Configuration
public class NacosConfig {
@Bean
public Converter<List<FlowRuleEntity>, String> flowRuleEntityEncoder() {
return JSON::toJSONString;
}
@Bean
public Converter<String, List<FlowRuleEntity>> flowRuleEntityDecoder() {
return s -> JSON.parseArray(s, FlowRuleEntity.class);
}
@Bean
public ConfigService nacosConfigService() throws Exception {
Properties properties = new Properties();
properties.put(PropertyKeyConst.SERVER_ADDR, "localhost");
return ConfigFactory.createConfigService(properties);
}
}
- e.我们需要对nacos的配置进行远程拉取,代码如下:
package com.alibaba.csp.sentinel.dashboard.rule.nacos;
import com.alibaba.csp.sentinel.dashboard.datasource.entity.rule.FlowRuleEntity;
import com.alibaba.csp.sentinel.dashboard.rule.DynamicRuleProvider;
import com.alibaba.csp.sentinel.datasource.Converter;
import com.alibaba.csp.sentinel.util.StringUtil;
import com.alibaba.nacos.api.config.ConfigService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import java.util.ArrayList;
import java.util.List;
/**
* @author cb
*/
@Component("flowRuleNacosProvider")
public class FlowRuleNacosProvider implements DynamicRuleProvider<List<FlowRuleEntity>> {
@Autowired
private ConfigService configService;
@Autowired
private Converter<String, List<FlowRuleEntity>> converter;
public static final String FLOW_DATA_ID_POSTFIX = "-sentinel";
public static final String GROUP_ID = "DEFAULT_GROUP";
@Override
public List<FlowRuleEntity> getRules(String appName) throws Exception {
String rules = configService.getConfig(appName + FLOW_DATA_ID_POSTFIX, GROUP_ID, 3000);
if (StringUtil.isEmpty(rules)) {
return new ArrayList<>();
}
return converter.convert(rules);
}
简单的来说下该类中的方法getRules的作用,我们看到参数为appName,其中appName为我们sentinel控制台中的应用名称,这个我们在上节大概都知道,还有我们看到配置了public static final String FLOW_DATA_ID_POSTFIX = "-sentinel"这个参数,该参数主要的目的是我们在nacos中的dataId的后缀,代码如下:
spring.cloud.sentinel.datasource.ds.nacos.dataId=${spring.application.name}-sentinel
spring.cloud.sentinel.datasource.ds.nacos.groupId=DEFAULT_GROUP
那么方法中的configService#getConfig(...)该方法就是为了动态获取我们在nacos管理台上的配置属性.
- f.完成了拉取远程的配置操作,我们需要将拉取的配置进行推送到sentinel平台完成展示,具体代码如下:
''''
package com.alibaba.csp.sentinel.dashboard.rule.nacos;
import com.alibaba.csp.sentinel.dashboard.datasource.entity.rule.FlowRuleEntity;
import com.alibaba.csp.sentinel.dashboard.rule.DynamicRulePublisher;
import com.alibaba.csp.sentinel.datasource.Converter;
import com.alibaba.csp.sentinel.util.AssertUtil;
import com.alibaba.nacos.api.config.ConfigService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import java.util.List;
/**
* @author cb
*/
@Component("flowRuleNacosPublisher")
public class FlowRuleNacosPublisher implements DynamicRulePublisher<List<FlowRuleEntity>> {
@Autowired
private ConfigService configService;
@Autowired
private Converter<List<FlowRuleEntity>, String> converter;
public static final String FLOW_DATA_ID_POSTFIX = "-sentinel";
public static final String GROUP_ID = "DEFAULT_GROUP";
@Override
public void publish(String app, List<FlowRuleEntity> rules) throws Exception {
AssertUtil.notEmpty(app, "app name cannot be empty");
if (rules == null) {
return;
}
configService.publishConfig(app + FLOW_DATA_ID_POSTFIX, GROUP_ID, converter.convert(rules));
}
}
- g.这也是最后一步,我们需要修该com.alibaba.csp.sentinel.dashboard.controller.v2.FlowControllerV2中DynamicRuleProvider和DynamicRulePublisher注入的bean操作,代码如下:
@Autowired
@Qualifier("flowRuleNacosProvider")
private DynamicRuleProvider<List<FlowRuleEntity>> ruleProvider;
@Autowired
@Qualifier("flowRuleNacosPublisher")
private DynamicRulePublisher<List<FlowRuleEntity>> rulePublisher;
到这里我们的sentinel Dashboard的修改完成了,启动它,我们会在控制台看到这样的日志输出:
微信截图_20191217214045.png
接着访问127.0.0.1:8080,会看到如图的界面:
微信截图_20191217214255.png
同样我们输入用户名和密码均为:sentinel,会看到如下图的主界面:
微信截图_20191217214322.png
那么以上便是关于sentinel Dashboard的修改操作,接下来是我们的重点,如何在nacos中定义我们的限流的规则
限流规则的定义
首先我们需要创建一个服务,我这里名字为alibaba-nacos-sentinel,没啥别的作用,主要是为了跟之前服务的对称,至于创建过程之前已经说了,接着我们来看需要的依赖,代码如下:
</parent>
<groupId>com.alibaba.sentinel</groupId>
<artifactId>alibaba-nacos-sentinel</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>alibaba-nacos-sentinel</name>
<description>利用sentinel实现限流</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- <dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
<version>2.1.0.RELEASE</version>
</dependency>-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
</dependency>
<!--nacos整合sentinel-->
<dependency>
<groupId>com.alibaba.csp</groupId>
<artifactId>sentinel-datasource-nacos</artifactId>
<version>1.7.0</version>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Greenwich.SR3</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-alibaba-dependencies</artifactId>
<version>0.9.0.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
- 接下来我们来看看配置文件,代码如下:
server.port=9007
spring.application.name=alibaba-nacos
spring.cloud.sentinel.transport.dashboard=127.0.0.1:8080
spring.cloud.sentinel.datasource.ds.nacos.server-addr=127.0.0.1:8848
spring.cloud.sentinel.datasource.ds.nacos.dataId=${spring.application.name}-sentinel
spring.cloud.sentinel.datasource.ds.nacos.groupId=DEFAULT_GROUP
spring.cloud.sentinel.datasource.ds.nacos.rule-type=flow
目前是学习阶段所以只是简单的配置我所用到的,这样看着简洁,当然大家可以配置成.yml文件格式,看个人
- 主程序,代码入下:
package com.alibaba.sentinel;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
* @author cb
*/
@SpringBootApplication
public class AlibabaNacosSentinelApplication {
public static void main(String[] args) {
SpringApplication.run(AlibabaNacosSentinelApplication.class, args);
}
}
- 测试接口代码入下;
package com.alibaba.sentinel.controller
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HelloController {
@GetMapping("/hello")
public String hello(){
return "hello Sentinel";
}
}
一个简单的接口测试,到这里我们需要的服务代码的编写完成了,接着启动我的本地注册中心nacos,接着启动我的服务,然后在nacos的管理台上配置我们的限流规则,如图所示:
微信截图_20191217220333.png
- 配置限流格式的代码如下:
{
"resource": "/hello",
"limitApp": "default",
"grade": 1,
"count": 5,
"strategy": 0,
"controlBehavior": 0,
"clusterMode": false
}
标准的json格式,同样我们就会在后台服务的日志中看到如图的信息:
微信截图_20191217220703.png
看到如图的信息,说明我们的配置能被服务加载到了,接着用postman来进行接口调用的测试,于此同时在我们sentinel 管理台上会出现相应服务的请求信息显示,如图:
微信截图_20191217221132.png
接着我们来查看流控规则,你会发现:
微信截图_20191217221326.png
那看到如图的信息,就说明我们借助于nacos管理台实现了限流规则的拉取和读取的过程,当然最重要的是持久化的过程,不信你可以关闭页面重新打开,配置的规则依然是存在的,到这里我们的目的也就达成了,关于sentinel的深入学习,大家可以看看官方文档....
