一、Gateway 集成Sentinel

Gateway网关集成Sentinel是为了流控、熔断、降级

1、 添加sentinel-spring-cloud-gateway-adapter依赖;

<!-- sentinel-spring-cloud-gateway-adapter
    Gateway集成Sentinel
 -->
<dependency>
    <groupId>com.alibaba.csp</groupId>
    <artifactId>sentinel-spring-cloud-gateway-adapter</artifactId>
    <version>1.8.0</version>
</dependency>

2、 添加sentinel控制台配置;

#sentinel dashboard管理后台
spring:
  cloud:
    sentinel:
      eager: true
      transport:
        dashboard: 192.168.172.128:8080

3、 在配置类spring容器中配置一个Sentinel的全局过滤器;

@Configuration
public class GatewayConfiguration {

    //省略号代表其它配置
    ......

    @Bean
    @Order(-1)
    public GlobalFilter sentinelGatewayFilter() {
        return new SentinelGatewayFilter();
    }

    ......
}

4、 启动测试;

(1)启动Nacos(如果使用MySQL数据持久化,则要先启动mysql服务)

cd /opt/software/nacos/bin/

sh startup.sh -m standalone

启动MySQL服务(如果docker启动,先启动docker并挂载mysql,防止数据丢失)

http://192.168.133.129:8848/nacos

(2)启动Sentinel DashBoard控制台

cd /opt/software/sentinel-dashboard-1.8.4/

java -jar sentinel-dashboard-1.8.4.jar

http://192.168.133.129:8080/

(3)分别启动服务提供者、服务消费者

(4)启动Spring Cloud Gateway

(5)浏览器输入访问

http://localhost:8081/test

二、Spring Cloud Gateway集成Sentinel规则持久化

一、使用SPI配置

1、 在application.properties中配置依赖;

<!--sentinel-datasource-extension数据源扩展-->
<dependency>
    <groupId>com.alibaba.csp</groupId>
    <artifactId>sentinel-datasource-extension</artifactId>
</dependency>

由于之前添加过了 spring-cloud-starter-alibaba-sentinel 依赖,包含了 sentinel-datasource 依赖,此处可以不加

 

2、 自定义FileDataSourceInit类实现InitFunc(配置文件暂时不动);

import com.alibaba.csp.sentinel.command.handler.ModifyParamFlowRulesCommandHandler;
import com.alibaba.csp.sentinel.datasource.*;
import com.alibaba.csp.sentinel.init.InitFunc;
import com.alibaba.csp.sentinel.slots.block.authority.AuthorityRule;
import com.alibaba.csp.sentinel.slots.block.authority.AuthorityRuleManager;
import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRule;
import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRuleManager;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRuleManager;
import com.alibaba.csp.sentinel.slots.block.flow.param.ParamFlowRule;
import com.alibaba.csp.sentinel.slots.block.flow.param.ParamFlowRuleManager;
import com.alibaba.csp.sentinel.slots.system.SystemRule;
import com.alibaba.csp.sentinel.slots.system.SystemRuleManager;
import com.alibaba.csp.sentinel.transport.util.WritableDataSourceRegistry;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
 
import java.io.File;
import java.io.IOException;
import java.util.List;
 
/**
 * 规则持久化
 */
public class FileDataSourceInit implements InitFunc {
 
    @Override
    public void init() throws Exception {
        //可以根据需要指定规则文件的位置
        //"user.home" 即C盘 C:\Users\用户名 下
        String ruleDir = System.getProperty("user.home") + "/sentinel/rules";
 
        String flowRulePath = ruleDir + "/flow-rule.json";
        String degradeRulePath = ruleDir + "/degrade-rule.json";
        String paramFlowRulePath = ruleDir + "/param-flow-rule.json";
        String systemRulePath = ruleDir + "/system-rule.json";
        String authorityRulePath = ruleDir + "/authority-rule.json";
 
        this.mkdirIfNotExits(ruleDir);
 
        this.createFileIfNotExits(flowRulePath);
        this.createFileIfNotExits(degradeRulePath);
        this.createFileIfNotExits(paramFlowRulePath);
        this.createFileIfNotExits(systemRulePath);
        this.createFileIfNotExits(authorityRulePath);
 
 
        //以下代码从官网拷贝过来
        // 流控规则:可读数据源
        ReadableDataSource<String, List<FlowRule>> flowRuleRDS = new FileRefreshableDataSource<>(
                flowRulePath,
                flowRuleListParser
        );
        // 将可读数据源注册至FlowRuleManager
        // 这样当规则文件发生变化时,就会更新规则到内存
        FlowRuleManager.register2Property(flowRuleRDS.getProperty());
        // 流控规则:可写数据源
        WritableDataSource<List<FlowRule>> flowRuleWDS = new FileWritableDataSource<>(
                flowRulePath,
                this::encodeJson
        );
        // 将可写数据源注册至transport模块的WritableDataSourceRegistry中
        // 这样收到控制台推送的规则时,Sentinel会先更新到内存,然后将规则写入到文件中
        WritableDataSourceRegistry.registerFlowDataSource(flowRuleWDS);
 
 
        // 降级规则:可读数据源
        ReadableDataSource<String, List<DegradeRule>> degradeRuleRDS = new FileRefreshableDataSource<>(
                degradeRulePath,
                degradeRuleListParser
        );
        DegradeRuleManager.register2Property(degradeRuleRDS.getProperty());
        // 降级规则:可写数据源
        WritableDataSource<List<DegradeRule>> degradeRuleWDS = new FileWritableDataSource<>(
                degradeRulePath,
                this::encodeJson
        );
        WritableDataSourceRegistry.registerDegradeDataSource(degradeRuleWDS);
 
 
        // 热点参数规则:可读数据源
        ReadableDataSource<String, List<ParamFlowRule>> paramFlowRuleRDS = new FileRefreshableDataSource<>(
                paramFlowRulePath,
                paramFlowRuleListParser
        );
        ParamFlowRuleManager.register2Property(paramFlowRuleRDS.getProperty());
        // 热点参数规则:可写数据源
        WritableDataSource<List<ParamFlowRule>> paramFlowRuleWDS = new FileWritableDataSource<>(
                paramFlowRulePath,
                this::encodeJson
        );
        ModifyParamFlowRulesCommandHandler.setWritableDataSource(paramFlowRuleWDS);
 
 
        // 系统规则:可读数据源
        ReadableDataSource<String, List<SystemRule>> systemRuleRDS = new FileRefreshableDataSource<>(
                systemRulePath,
                systemRuleListParser
        );
        SystemRuleManager.register2Property(systemRuleRDS.getProperty());
        // 系统规则:可写数据源
        WritableDataSource<List<SystemRule>> systemRuleWDS = new FileWritableDataSource<>(
                systemRulePath,
                this::encodeJson
        );
        WritableDataSourceRegistry.registerSystemDataSource(systemRuleWDS);
 
 
        // 授权规则:可读数据源
        ReadableDataSource<String, List<AuthorityRule>> authorityRuleRDS = new FileRefreshableDataSource<>(
                authorityRulePath,
                authorityRuleListParser
        );
        AuthorityRuleManager.register2Property(authorityRuleRDS.getProperty());
        // 授权规则:可写数据源
        WritableDataSource<List<AuthorityRule>> authorityRuleWDS = new FileWritableDataSource<>(
                authorityRulePath,
                this::encodeJson
        );
        WritableDataSourceRegistry.registerAuthorityDataSource(authorityRuleWDS);
    }
 
 
    private Converter<String, List<FlowRule>> flowRuleListParser = source -> JSON.parseObject(
            source,
            new TypeReference<List<FlowRule>>() {
            }
    );
 
    private Converter<String, List<DegradeRule>> degradeRuleListParser = source -> JSON.parseObject(
            source,
            new TypeReference<List<DegradeRule>>() {
            }
    );
 
    private Converter<String, List<SystemRule>> systemRuleListParser = source -> JSON.parseObject(
            source,
            new TypeReference<List<SystemRule>>() {
            }
    );
 
    private Converter<String, List<AuthorityRule>> authorityRuleListParser = source -> JSON.parseObject(
            source,
            new TypeReference<List<AuthorityRule>>() {
            }
    );
 
    private Converter<String, List<ParamFlowRule>> paramFlowRuleListParser = source -> JSON.parseObject(
            source,
            new TypeReference<List<ParamFlowRule>>() {
            }
    );
 
    private void mkdirIfNotExits(String filePath) throws IOException {
        File file = new File(filePath);
        if (!file.exists()) {
            file.mkdirs();
        }
    }
 
    private void createFileIfNotExits(String filePath) throws IOException {
        File file = new File(filePath);
        if (!file.exists()) {
            file.createNewFile();
        }
    }
 
    private <T> String encodeJson(T t) {
        return JSON.toJSONString(t);
    }
}

3、 配置SPI(ServiceProviderInterface,JDK内置的一种服务提供发现机制,可以用来启用框架扩展和替换组件);

Java SPI是一种以接口为基础,使用配置文件来加载(或称之为服务发现)的动态加载机制,主要使用JDK中ServiceLoader来实现

(1)在classPath下 resources 创建路径META-INF/services/目录下 创建一个 文件 com.alibaba.csp.sentinel.init.InitFunc(以接口的全路径做为名称,不要带文件格式后缀)

(2)将自定义的类 包路径名拷贝至此(实现类的全路径)

   

 

4、 启动消费者服务,此时去SentinelDashBoard中创建一条流控规则;

 根据自定义类 FileDataSourceInit 中 存放sentinel 规则的文件夹,

即C:\Users\用户名\sentinel\rules 可找到相应Sentinel 规则持久化的JSON文件

        //可以根据需要指定规则文件的位置
        //"user.home" 即C盘 C:\Users\用户名 下
        String ruleDir = System.getProperty("user.home") + "/sentinel/rules";

 

二、使用Nacos配置

1、 添加sentinel-datasource-nacos依赖;

<!--sentinel数据持久化-->
<dependency>
    <groupId>com.alibaba.csp</groupId>
    <artifactId>sentinel-datasource-nacos</artifactId>
</dependency>

2、 application.properties配置持久化数据源;

#配置sentinel规则持久化到nacos
datasource:
  ncs1:
    nacos:
      server-addr: 192.168.133.128:80
      data-id: ${spring.application.name}.json
      group-id: DEFAULT_GROUP
      rule-type: flow
      data-type: json

degrade:
   nacos:
     server-addr: 192.168.133.128:80
     data-id: ${spring.application.name}-degrade.json
     group-id: DEFAULT_GROUP
     rule-type: degrade
     data-type: json

3、 在nacos配置中心配置流控规则;

[
  {
    "resource": "abc",
    "controlBehavior": 0,
    "count": 1.0,
    "grade": 1,
    "limitApp": "default",
    "strategy": 0
  }
]

三、Sprng Cloud Gateway跨域CORS

可参考https://blog.csdn.net/MinggeQingchun/article/details/125538531

传统的Ajax请求只能获取在同一个域名下的资源,但是HTML5规范中打破了这种限制,允许Ajax发起跨域的请求(需要设置一下)

其实浏览器本身是可以发起跨域请求的,比如你可以链接一个另一个域名下的图片或者js,比如,但是javascript脚本是不能获取这些另一个域名下的资源内容的

CORS是一个W3C标准,全称是”跨域资源共享”(Cross-origin resource sharing),允许浏览器向跨源服务器,发出XMLHttpRequest请求,从而克服了AJAX只能同源使用的限制

这种CORS使用了一个额外的HTTP响应头来赋予当前user-agent(浏览器)获得跨域资源的权限,这里的跨域也就是Cross-Origin的概念,这里的权限就是访问另一个域名下的资源权限

CORS是现在HTML5标准中的一部分,在大部分现代浏览器中都有所支持,可能在某些老版本的浏览器不支持CORS,如果要兼容一些老的浏览器版本,则需要采用JSONP进行跨域请求

同源与非同源(跨域和不跨域)

如果 访问****协议、端口(如果指定了端口)、host 都相同,则称之为同源****(不跨域) ,否则为非同源(跨域)

如源链接: http://shop.company.com/good/page.html

URL

是否同源

原因

http://shop.company.com/good2/other.html

http://shop.company.com/good/inner/another.html

https://shop.company.com/good.html

协议不同

http://shop.company.com:81/good/etc.html

端口不同

http://news.company.com/good/other.html

host不同

解决跨域:

/**
 * 配置网关跨域cors请求支持
 */
@Configuration
public class CorsConfig {

    @Bean
    public CorsWebFilter corsFilter() {
        CorsConfiguration config = new CorsConfiguration();
        config.addAllowedMethod("*"); //是什么请求方法,比如 GET POST PUT DELATE .....
        config.addAllowedOrigin("*"); //来自哪个域名的请求,*号表示所有
        config.addAllowedHeader("*"); //是什么请求头

        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource(new PathPatternParser());
        source.registerCorsConfiguration("/**", config);

        return new CorsWebFilter(source);
    }
}