Spring Cloud Alibab 入门搭建，包含Nacos中心，注册服务发现服务，Feign请求，GateWay网关，sentinel限流

一、安装Nacos注册中心

1.1查看Nacos官网，安装Nacos服务，下载源码或者安装包

1.2启动服务，默认端口为8848，

二、创建服务注册&发现

2.1使用脚手架，创建注册服务和发现服务项目，我用的版本是2.6.13，

2.2增加启动类配置，用于支持注册服务和发现服务和Feign请求等

2.2.1注册服务增加配置类注解

2.2.2发现服务配置，激活Feign

2.2.3创建包nacosdiscoveryprovider，包下创建接口EchoServiceController作为注册服务接口，用于后续Feign请求测试，启动服务

2.2.4创建发现服务普通RestTemplate接口，测试通过RestTemplate请求是否可以转发到注册服务端

2.2.5创建Feign接口

三、创建网关服务

3.1 脚手架创建网关服务

3.2启动类增加注解

3.3创建Controller接口测试服务是否可以正常访问

4.网关服务作为统一入口，需要配置断言Predicate机制拦截，一个请求在抵达网关层后，首先就要进行断言匹配，在满足所有断言之后才会进入Filter阶段转发至发现服务nacos-discovery-provider-sample，断言配置采用Nacos中心动态配置。

4.1在Nacos中心创建配置

4.2 网关服务application.properties增加配置获取Nacos中心的配置

4.3动态刷新中心配置

4.4增加配置类事件推送类，动态更新配置DynamicRouteServiceImpl

4.5项目创建DynamicRouteServiceImplNacos类，用于接收动态刷新。

4.5启动网关服务，Postman调用网关

5.网关配置JTWtoken鉴权

5.1自定义过滤器鉴权规则

5.2修改Nacos中心nacos-gateway-sample.json断言配置，增加过滤器

5.3增加模拟登录接口获取token

四、为服务增加sentinel限流熔断配置

4.1下载按照运行sentinel

4.2网关服务配置sentinel

4.3配置限流规则

4.3.1选择API管理，新增API规则

4.3.2新增网关流控规则

4.3.3配置熔断规则

4.3.4配置限流和熔断统一返回值，此例是返回值，

五、限流熔断配置Nacos持久化

5.1Nacos控制台新建一个限流和熔断配置

5.1.1限流配置：

5.1.1熔断配置

5.2项目配置文件增加nacos的数据源配置

5.3创建config类，初始化加载配置参数属性

5.4创建限流熔断工厂类，加载sentinel相关内容。加载限流、熔断规则，自定义限流熔断错误返回处理，

5.5 Postman测试

5.5.1限流生效返回

5.5.2熔断生效返回

六结束语

一、安装Nacos注册中心

1.1查看Nacos官网，安装Nacos服务，下载源码或者安装包

Nacos 快速开始

1.2启动服务，默认端口为8848，

进入文件夹，cd nacos/bin

以单机模式启动服务

sh startup.sh -m standalone

登录注册中心查看服务是否正常

`二、创建`服务注册&发现

2.1使用脚手架，创建注册服务和发现服务项目，我用的版本是2.6.13，

项目名称nacos-discovery-provider-sample

脚手架创建的服务包含注册和发现

Cloud Native App Initializer (aliyun.com)

选择组件

项目pom完整内容

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>nacos-discovery-provider-sample</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>nacos-discovery-provider-sample</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <spring-boot.version>2.6.13</spring-boot.version>
        <spring-cloud-alibaba.version>2021.0.5.0</spring-cloud-alibaba.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-nacos-discovery</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-loadbalancer</artifactId>
            <version>3.1.5</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
            <version>3.1.5</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${spring-cloud-alibaba.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

        </dependencies>
    </dependencyManagement>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>${spring-boot.version}</version>
                <configuration>
                    <mainClass>com.alibaba.cloud.nacosdiscoveryprovidersample.NacosDiscoveryProviderSampleApplication</mainClass>
                    <skip>true</skip>
                </configuration>
                <executions>
                    <execution>
                        <id>repackage</id>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

application.properties内容

默认服务名

spring.application.name=nacos-discovery-provider-sample

# Nacos帮助文档: https://nacos.io/zh-cn/docs/concepts.html
spring.application.name=nacos-discovery-provider-sample
# Nacos认证信息
spring.cloud.nacos.discovery.username=nacos
spring.cloud.nacos.discovery.password=nacos
# Nacos 服务发现与注册配置，其中子属性 server-addr 指定 Nacos 服务器主机和端口
spring.cloud.nacos.discovery.server-addr=192.168.100.115:8848
# 注册到 nacos 的指定 namespace，默认为 public
spring.cloud.nacos.discovery.namespace=23963657-2b3b-49db-be69-f2517dc3695c
#ribbon.nacos.enabled=true
server.port=8082

2.2增加启动类配置，用于支持注册服务和发现服务和Feign请求等

2.2.1注册服务增加配置类注解

@EnableDiscoveryClient 开启服务提供者或消费者，客户端的支持，用来注册服务

@EnableFeignClients 开启Feign功能

配置类注解@Configuration

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.cloud.nacosdiscoveryprovidersample.nacosdiscovery;

import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.context.annotation.Configuration;

/**
 * @author <a href="mailto:chenxilzx1@gmail.com">theonefx</a>
 */
@EnableDiscoveryClient
@Configuration
@EnableFeignClients
public class NacosDiscoveryConfiguration {
}

2.2.2发现服务配置，激活Feign

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 package com.alibaba.cloud.nacosdiscoveryprovidersample.demos.nacosdiscoveryconsumer;

import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.context.annotation.Configuration;
@EnableFeignClients // 激活 @FeignClient
@Configuration
public class NacosDiscoveryConsumerConfiguration {

}

2.2.3创建包nacosdiscoveryprovider，包下创建接口EchoServiceController作为注册服务接口，用于后续Feign请求测试，启动服务

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.cloud.nacosdiscoveryprovidersample.demos.nacosdiscoveryprovider;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class EchoServiceController {

    @GetMapping("/echo/{message}")
    public String echo(@PathVariable String message) throws InterruptedException {
        System.out.println(message);
        return "[ECHO] : " + message;
    }
    @GetMapping("/test")
    public String test() {
        return "[ECHO] : " +"test";
    }
}

2.2.4创建发现服务普通RestTemplate接口，测试通过RestTemplate请求是否可以转发到注册服务端

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 package com.alibaba.cloud.nacosdiscoveryprovidersample.demos.nacosdiscoveryconsumer;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Lazy;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import java.util.concurrent.Delayed;


@RestController
public class RestTemplateController {

    @LoadBalanced
    @Lazy
    @Autowired
    public RestTemplate restTemplate;
    @LoadBalanced
    @Bean
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }

    @GetMapping("/call/echo/{message}")
    public String callEcho(@PathVariable String message) throws InterruptedException {
        // 访问应用 nacos-discovery-provider-sample 的 EchoServiceController 中的/echo/{message}
        return restTemplate.getForObject("http://nacos-discovery-provider-sample/echo/" + message, String.class);
    }
}

Postman 调用本服务接口 /call/echo/{message}，正常访问到接口之后，RestTemplate通过路由

http://nacos-discovery-provider-sample/echo/ 路由前缀为注册服务名称转发的上述

nacosdiscoveryprovider包下接口EchoServiceController。

2.2.5创建Feign接口

创建发现服务Feign 接口，用于接收Feign请求转发只服务端，接口增加注解

@FeignClient("nacos-discovery-provider-sample") 指向服务提供者应用

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.cloud.nacosdiscoveryprovidersample.demos.nacosdiscoveryconsumer;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;

@FeignClient("nacos-discovery-provider-sample") // 指向服务提供者应用
public interface EchoService {

    @GetMapping("/echo/{message}")
    String echo(@PathVariable("message") String message);
}

创建FeignController 测试Feign请求

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 package com.alibaba.cloud.nacosdiscoveryprovidersample.demos.nacosdiscoveryconsumer;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class OpenFeignController {

    @Autowired
    private EchoService echoService;

    @GetMapping("/feign/echo/{message}")
    public String feignEcho(@PathVariable String message) throws InterruptedException {
        return echoService.echo(message);
    }
}

通过Postman 请求接口/feign/echo/{message}

服务根据EchoService 中的FeignClient注解，请求会转发至nacos-discovery-provider-sample服务的/echo/{message}接口

至此，Nacos中心搭建完成，注册服务和发现服务注册成功，并且服务支持Fdign请求。

三、创建网关服务

3.1 脚手架创建网关服务

Cloud Native App Initializer (aliyun.com)

项目pom完整内容

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>nacos-gateway-sample</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>nacos-gateway-sample</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <spring-boot.version>2.6.13</spring-boot.version>
        <spring-cloud-alibaba.version>2021.0.5.0</spring-cloud-alibaba.version>
    </properties>
    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
            <version>3.1.5</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-alibaba-sentinel-gateway</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-gateway-server</artifactId>
            <version>3.1.5</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
        </dependency>
         <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-loadbalancer</artifactId>
            <version>3.1.5</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.4</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.76</version>
        </dependency>
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.3.10</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-gateway-server</artifactId>
            <version>3.1.5</version>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
            <version>0.9.0</version>
        </dependency>
        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
            <version>2.3.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-crypto</artifactId>
        </dependency>

    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${spring-cloud-alibaba.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>${spring-boot.version}</version>
                <configuration>
                    <mainClass>com.alibaba.cloud.nacosgatewaysample.NacosGatewaySampleApplication</mainClass>
                    <skip>true</skip>
                </configuration>
                <executions>
                    <execution>
                        <id>repackage</id>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

</project>

application.properties

# Nacos帮助文档: https://nacos.io/zh-cn/docs/concepts.html
spring.application.name=nacos-gateway-sample
server.port=9080
# Nacos认证信息
spring.cloud.nacos.discovery.username=nacos
spring.cloud.nacos.discovery.password=nacos
## 整合sentinel，配置sentinel控制台的地址## 指定控制台的地址，默认端口8080
spring.cloud.sentinel.enabled=true

spring.main.allow-bean-definition-overriding: true
# Nacos 服务发现与注册配置，其中子属性 server-addr 指定 Nacos 服务器主机和端口
spring.cloud.nacos.discovery.server-addr=192.168.100.115:8848
# 注册到 nacos 的指定 namespace，默认为 public
spring.cloud.nacos.discovery.namespace=23963657-2b3b-49db-be69-f2517dc3695c
#sentinel控制台
spring.cloud.sentinel.transport.dashboard=192.168.100.115:9090
##限流或者熔断返回
## 一种是redirect，重定向跳转，需要同时配置redirect(跳转的uri)
spring.cloud.sentinel.scg.fallback.mode=response
## 响应的状态
spring.cloud.sentinel.scg.fallback.response-status=200
## 响应体
spring.cloud.sentinel.scg.fallback.response-body='{"code": 200,"message": "限流/熔断，稍后重试！"}'


nacos.gateway.route.config.data-id=nacos-gateway-sample.json
nacos.gateway.route.config.group=DEFAULT_GROUP
murg.gateway.jwt.enabled=true
murg.gateway.jwt.secret=fjkfaf;afa
murg.gateway.jwt.header=Authorization
murg.gateway.jwt.expiration=3000000000000000
murg.gateway.jwt.userParamName=username
murg.gateway.jwt.pwdParamName=password

3.2启动类增加注解@EnableDiscoveryClient

启动服务，登录Nacos注册中心，查看网关服务是否正常注册。

3.3创建Controller接口测试服务是否可以正常访问

JwtAuthController

  /**
     * 测试
     */
    @RequestMapping("/aaa/test")
    public String testaaa(@RequestBody Map<String,String> map) throws InterruptedException {
        Thread.sleep(3000);
        return "aaaaaa";
    }

Postman测试请求/aaa/test

正常返回数据。

4.网关服务作为统一入口，需要配置断言Predicate机制拦截，一个请求在抵达网关层后，首先就要进行断言匹配，在满足所有断言之后才会进入Filter阶段转发至发现服务nacos-discovery-provider-sample，断言配置采用Nacos中心动态配置。

4.1在Nacos中心创建配置

本例采用Json格式，配置详情如下

[
{
"id":"nacos-gateway-sample",
"order":0,
"predicates":[
{
"args":{
"pattern":"/nacos-discovery-provider-sample/**" //路由匹配内容
},
"name":"Path" //通过路由方式拦截
}
],
"uri":"lb://nacos-discovery-provider-sample",//匹配成功转发到的服务地址
}
]

注：中心配置内不能有注释，在中心把注释删除

4.2 网关服务application.properties增加配置获取Nacos中心的配置

nacos.gateway.route.config.data-id=nacos-gateway-sample.json
nacos.gateway.route.config.group=DEFAULT_GROUP

启动网关服务，会自动加载Nacos中心中的网关断言配置

4.3动态刷新中心配置

Nacos中心的断言配置如有变化，为了不重新服务，可以创建动态监听配置类，动态刷新

首先需要创建一个网报配置类GatewayConfig，读取Nacos相关访问配置，为配置监听做准备

package com.alibaba.cloud.nacosgatewaysample.config;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
/**
 * 配置类：读取Nacos相关的配置项，用于配置监听器
 */
@SuppressWarnings("all")
@Configuration
public class GatewayConfig {
        /**
         * 读取配置的超时时间
         */
        public static final long DEFAULT_TIMEOUT = 30000;
        /**
         * Nacos 服务器地址
         */
        public static String NACOS_SERVER_ADDR;
        /**
         * Nacos 命名空间
         */
        public static String NACOS_NAMESPACE;
        /**
         * nacos 配置列表中的dataid
         */
        public static String NACOS_ROUTE_DATE_ID;
        /**
         * nacos分组id
         */
        public static String NACOS_GROUP_ID;
        @Value("${spring.cloud.nacos.discovery.server-addr}")
        public void setNacosServerAddr(String nacosServerAddr) {
            NACOS_SERVER_ADDR = nacosServerAddr;
        }
        @Value("${spring.cloud.nacos.discovery.namespace}")
        public void setNacosNamespace(String nacosNamespace) {
            NACOS_NAMESPACE = nacosNamespace;
        }
        @Value("${nacos.gateway.route.config.data-id}")
        public void setNacosRouteDateId(String nacosRouteDateId) {
            NACOS_ROUTE_DATE_ID = nacosRouteDateId;
        }
        @Value("${nacos.gateway.route.config.group}")
        public void setNacosGroupId(String nacosGroupId) {
            NACOS_GROUP_ID = nacosGroupId;
        }

}

4.4增加配置类事件推送类，动态更新配置DynamicRouteServiceImpl

package com.alibaba.cloud.nacosgatewaysample.config;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.event.RefreshRoutesEvent;
import org.springframework.cloud.gateway.route.RouteDefinition;
import org.springframework.cloud.gateway.route.RouteDefinitionLocator;
import org.springframework.cloud.gateway.route.RouteDefinitionWriter;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.ApplicationEventPublisherAware;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import reactor.core.publisher.Mono;
import java.util.List;

/**
 * 事件推送 Aware: 动态更新路由网关 Service
 * */
@Slf4j
@Service
@SuppressWarnings("all")
public class DynamicRouteServiceImpl implements ApplicationEventPublisherAware {
    /** 写路由定义 */
    private final RouteDefinitionWriter routeDefinitionWriter;
    /** 获取路由定义 */
    private final RouteDefinitionLocator routeDefinitionLocator;
    /** 事件发布 */
    private ApplicationEventPublisher publisher;
    public DynamicRouteServiceImpl(RouteDefinitionWriter routeDefinitionWriter,
                                   RouteDefinitionLocator routeDefinitionLocator) {
        this.routeDefinitionWriter = routeDefinitionWriter;
        this.routeDefinitionLocator = routeDefinitionLocator;
    }
    @Override
    public void setApplicationEventPublisher(
            ApplicationEventPublisher applicationEventPublisher) {
        // 完成事件推送句柄的初始化
        this.publisher = applicationEventPublisher;
    }

    /**
     * 从nacos读取路由配hi，写道gateway中
     * <h2>增加路由定义</h2>
     * */
    public String addRouteDefinition(RouteDefinition definition) {
        log.info("gateway add route: [{}]", definition);
        // 保存路由配置并发布
        routeDefinitionWriter.save(Mono.just(definition)).subscribe();
        // 发布事件通知给 Gateway, 同步新增的路由定义
        this.publisher.publishEvent(new RefreshRoutesEvent(this));
        return "success";
    }
    /**
     * <h2>更新路由</h2>
     * */
    public String updateList(List<RouteDefinition> definitions) {
        log.info("更新网关路由: [{}]", definitions);
        // 先拿到当前 Gateway 中存储的路由定义
        List<RouteDefinition> routeDefinitionsExits =
                routeDefinitionLocator.getRouteDefinitions().buffer().blockFirst();
        if (!CollectionUtils.isEmpty(routeDefinitionsExits)) {
            // 清除掉之前所有的 "旧的" 路由定义
            routeDefinitionsExits.forEach(rd -> {
                deleteById(rd.getId());
                log.info("清除掉之前所有的 旧的 路由定义: [{}]", rd);
            });
        }
        // 把更新的路由定义同步到 gateway 中
        definitions.forEach(definition -> updateByRouteDefinition(definition));
        return "success";
    }

    /**
     * <h2>根据路由 id 删除路由配置</h2>
     * */
    private String deleteById(String id) {
        try {
            log.info("要删除的路由id: [{}]", id);
            this.routeDefinitionWriter.delete(Mono.just(id)).subscribe();
            // 发布事件通知给 gateway 更新路由定义
            this.publisher.publishEvent(new RefreshRoutesEvent(this));
            return "删除成功";
        } catch (Exception ex) {
            log.error("删除网关路由失败: [{}]", ex.getMessage(), ex);
            return "删除失败";
        }
    }

    /**
     * <h2>更新路由</h2>
     * 更新的实现策略比较简单: 删除 + 新增 = 更新
     * */
    private String updateByRouteDefinition(RouteDefinition definition) {

        try {
            log.info("更新网关路由: [{}]", definition);
            this.routeDefinitionWriter.delete(Mono.just(definition.getId()));
        } catch (Exception ex) {
            return "更新失败,没有查到更新的网关路由id: " + definition.getId();
        }

        try {
            this.routeDefinitionWriter.save(Mono.just(definition)).subscribe();
            this.publisher.publishEvent(new RefreshRoutesEvent(this));
            return "成功";
        } catch (Exception ex) {
            return "更新路由失败！";
        }
    }
}

4.5项目创建DynamicRouteServiceImplNacos类，用于接收动态刷新。

package com.alibaba.cloud.nacosgatewaysample.config;
import cn.hutool.core.collection.CollectionUtil;
import com.alibaba.fastjson.JSON;
import com.alibaba.nacos.api.NacosFactory;
import com.alibaba.nacos.api.config.ConfigService;
import com.alibaba.nacos.api.config.listener.Listener;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.route.RouteDefinition;
import org.springframework.context.annotation.DependsOn;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import java.util.List;
import java.util.Properties;
import java.util.concurrent.Executor;

/**
 * 通过Nacos下发的动态配置，监听nacos中路由配置
 */
@Slf4j
@Component
//再另外一个Bean初始化之后再去初始化当前类
@DependsOn({"gatewayConfig"})
@SuppressWarnings("all")
public class DynamicRouteServiceImplNacos {
    private ConfigService configService;
    private final DynamicRouteServiceImpl dynamicRouteService;
 public DynamicRouteServiceImplNacos(DynamicRouteServiceImpl dynamicRouteService){
        this.dynamicRouteService = dynamicRouteService;
    }
 /**
     * 初始化ConfigService
     *
     * @return
     */
    private ConfigService initConfigService() {
        try {
            Properties properties = new Properties();
            properties.setProperty("serverAddr", GatewayConfig.NACOS_SERVER_ADDR);
            properties.setProperty("namespace", GatewayConfig.NACOS_NAMESPACE);
            return configService = NacosFactory.createConfigService(properties);
        } catch (Exception ex) {
            log.error("初始化配置服务:[{}]", ex.getMessage());
            return null;
        }
    }
 /**
     * bean在容器中构造完成之后会立即执行当前的init方法
     * 加载路由信息，注册监听器
     */
    @PostConstruct
    public void init(){
        log.info("网关路由初始化...");
 try {
            //初始化nacos配置客户端
            configService = initConfigService();
            if(configService==null){
                log.error("初始化配置服务异常,配置服务是null!");
                return;
            }
            //通过 nacos config 并指定路由配置路径去获取路由配置
            String configInfo = configService.getConfig(GatewayConfig.NACOS_ROUTE_DATE_ID,
                    GatewayConfig.NACOS_GROUP_ID,
                    GatewayConfig.DEFAULT_TIMEOUT);
            log.info("当前网关配置信息:[{}]:",configInfo);
            //反序列化
            List<RouteDefinition> routeDefinitions = JSON.parseArray(configInfo, RouteDefinition.class);
            if(CollectionUtil.isNotEmpty(routeDefinitions)){
                //新增
                for (RouteDefinition routeDefinition : routeDefinitions) {
                    log.info("初始化 路由定义对象 信息:[{}]:",routeDefinition);
                    dynamicRouteService.addRouteDefinition(routeDefinition);
                }

            }
        } catch (Exception e) {
            log.error("网关路由初始化失败:[{}]",e.getMessage());
        }
        //设置监听器
        dynamicRouteServiceImplNacosByListener(GatewayConfig.NACOS_ROUTE_DATE_ID, GatewayConfig.NACOS_GROUP_ID);
    }

    /**
     * 监听 Nacos下发的动态路由配置
     *
     * @param dataId
     * @param group
     */
    private void dynamicRouteServiceImplNacosByListener(String dataId, String group) {
        try {
            //给Nacos config 客户端增加一个监听器
            configService.addListener(dataId, group, new Listener() {
                /**
                 * 自己提供线程池执行操作
                 * @return
                 */
                @Override
                public Executor getExecutor() {
                    return null;
                }

                /**
                 * 监听器收到接收到配置变更信息
                 * @param configInfo nacos 中最新配置信息
                 */
                @Override
                public void receiveConfigInfo(String configInfo) {
                    log.info("接收的配置信息:[{}]", configInfo);
                    List<RouteDefinition> routeDefinitions = JSON.parseArray(configInfo, RouteDefinition.class);
                    dynamicRouteService.updateList(routeDefinitions);
                    log.info("更新后的路由配置信息:[{}]", routeDefinitions.toString());
                }
            });
        } catch (Exception e) {
            log.error("监听 Nacos下发的动态路由配置异常:[{}]", e.getMessage());
        }
    }
}

Nacos中心配置变更发布之后，监听更新，调用DynamicRouteServiceImpl updateList 实现更新配置

4.5启动网关服务，Postman调用网关

路由/nacos-discovery-provider-sample/call/echo/nnn

根据断言配置的 "pattern":"/nacos-discovery-provider-sample/**" 匹配到前缀，网关自动转发至

发现服务nacos-discovery-provider-sample的/call/echo/nnn接口，控制台输出nnn

5.网关配置JTWtoken鉴权

为网关配置鉴权过滤器

pom引入以下配置

<dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
            <version>0.9.0</version>
        </dependency>
        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
            <version>2.3.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-crypto</artifactId>
        </dependency>

5.1自定义过滤器鉴权规则

创建JwtProperties类

package com.alibaba.cloud.nacosgatewaysample.config;

import lombok.Data;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

@Data
@ConfigurationProperties(prefix = "murg.gateway.jwt")
@Component
public class JwtProperties {

    //是否开启JWT，即注入相关的类对象
    private Boolean enabled;
    //JWT密钥
    private String secret;
    //JWT有效时间
    private Long expiration;
    //前端向后端传递JWT时使用HTTP的header名称，前后端要统一
    private String header;
    //用户登录-用户名参数名称
    private String userParamName = "username";
    //用户登录-密码参数名称
    private String pwdParamName = "password";


}

application.properties增加 JWT配置

murg.gateway.jwt.enabled=true
murg.gateway.jwt.secret=fjkfaf;afa
murg.gateway.jwt.header=Authorization
murg.gateway.jwt.expiration=3000000000000000
murg.gateway.jwt.userParamName=username
murg.gateway.jwt.pwdParamName=password

创建JTWUtile，鉴权逻辑

package com.alibaba.cloud.nacosgatewaysample.config;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

@Component
public class JwtTokenUtil {

    @Resource
    private JwtProperties jwtProperties;


    /**
     * 生成token令牌
     *
     * @param userId 用户Id或用户名
     * @param payloads 令牌中携带的附加信息
     * @return 令token牌
     */
    public String generateToken(String userId,
                                Map<String,String> payloads) {
        int payloadSizes = payloads == null? 0 : payloads.size();

        Map<String, Object> claims = new HashMap<>(payloadSizes + 2);
        claims.put("sub", userId);
        claims.put("created", new Date());

        if(payloadSizes > 0){
            for(Map.Entry<String,String> entry:payloads.entrySet()){
                claims.put(entry.getKey(),entry.getValue());
            }
        }

        return generateToken(claims);
    }

    /**
     * 从令牌中获取用户名
     *
     * @param token 令牌
     * @return 用户名
     */
    public String getUsernameFromToken(String token) {
        String username;
        try {
            Claims claims = getClaimsFromToken(token);
            username = claims.getSubject();
        } catch (Exception e) {
            username = null;
        }
        return username;
    }

    /**
     * 判断令牌是否过期
     *
     * @param token 令牌
     * @return 是否过期
     */
    public Boolean isTokenExpired(String token) {
        try {
            Claims claims = getClaimsFromToken(token);
            Date expiration = claims.getExpiration();
            return expiration.before(new Date());
        } catch (Exception e) {
            //验证JWT签名失败等同于令牌过期
            return true;
        }
    }

    /**
     * 刷新令牌
     *
     * @param token 原令牌
     * @return 新令牌
     */
    public String refreshToken(String token) {
        String refreshedToken;
        try {
            Claims claims = getClaimsFromToken(token);
            claims.put("created", new Date());
            refreshedToken = generateToken(claims);
        } catch (Exception e) {
            refreshedToken = null;
        }
        return refreshedToken;
    }

    /**
     * 验证令牌
     *
     * @param token       令牌
     * @param userId  用户Id用户名
     * @return 是否有效
     */
    public Boolean validateToken(String token, String userId) {

        String username = getUsernameFromToken(token);
        return (username.equals(userId) && !isTokenExpired(token));
    }


    /**
     * 从claims生成令牌,如果看不懂就看谁调用它
     *
     * @param claims 数据声明
     * @return 令牌
     */
    private String generateToken(Map<String, Object> claims) {
        Date expirationDate = new Date(System.currentTimeMillis() + jwtProperties.getExpiration());
        return Jwts.builder().setClaims(claims)
                .setExpiration(expirationDate)
                .signWith(SignatureAlgorithm.HS512, jwtProperties.getSecret())
                .compact();
    }

    /**
     * 从令牌中获取数据声明,验证JWT签名
     *
     * @param token 令牌
     * @return 数据声明
     */
    private Claims getClaimsFromToken(String token) {
        Claims claims;
        try {
            claims = Jwts.parser().setSigningKey(jwtProperties.getSecret()).parseClaimsJws(token).getBody();
        } catch (Exception e) {
            claims = null;
        }
        return claims;
    }
}

创建JWTAuthCheckFilter自定义过滤规则实现JTW鉴权，@Order注解配置自动注入顺序后注入，防止先加载。

/authentication模拟登录注册接口，此接口放行。

package com.alibaba.cloud.nacosgatewaysample.Filter;

import com.alibaba.cloud.nacosgatewaysample.config.JwtProperties;
import com.alibaba.cloud.nacosgatewaysample.config.JwtTokenUtil;
import com.alibaba.fastjson.JSON;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

import javax.annotation.Resource;
import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Map;

@Configuration
@Order(-101)
public class JWTAuthCheckFilter  implements GatewayFilter, Ordered  {
  @Resource
  private JwtProperties jwtProperties;
  @Resource
  private JwtTokenUtil jwtTokenUtil;



  //将JWT鉴权失败的消息响应给客户端
  private Mono<Void> writeUnAuthorizedMessageAsJson(ServerHttpResponse serverHttpResponse, String message) {
    serverHttpResponse.setStatusCode(HttpStatus.UNAUTHORIZED);
    Map reuslt=new HashMap();
    reuslt. put("code","401");
    reuslt. put("msg","鉴权失败");
    serverHttpResponse.getHeaders().add("Content-Type", "application/json;charset=UTF-8");
    DataBuffer dataBuffer = serverHttpResponse.bufferFactory()
            .wrap(JSON.toJSONStringWithDateFormat(reuslt,JSON.DEFFAULT_DATE_FORMAT)
                    .getBytes(StandardCharsets.UTF_8));
    return serverHttpResponse.writeWith(Flux.just(dataBuffer));
  }

  @Override
  public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
    ServerHttpRequest serverHttpRequest = exchange.getRequest();
    ServerHttpResponse serverHttpResponse = exchange.getResponse();
    String requestUrl = serverHttpRequest.getURI().getPath();

    if(!requestUrl.equals("/authentication")){
      //从HTTP请求头中获取JWT令牌
      String jwtToken = serverHttpRequest
              .getHeaders()
              .getFirst(jwtProperties.getHeader());
      //对Token解签名，并验证Token是否过期
      boolean isJwtNotValid = jwtTokenUtil.isTokenExpired(jwtToken);
      if(isJwtNotValid){ //如果JWT令牌不合法
        return writeUnAuthorizedMessageAsJson(serverHttpResponse,"请先去登录，再访问服务！");
      }
      //从JWT中解析出当前用户的身份（userId），并继续执行过滤器链，转发请求
      ServerHttpRequest mutableReq = serverHttpRequest
              .mutate()
              .header("userId", jwtTokenUtil.getUsernameFromToken(jwtToken))
              .build();
      ServerWebExchange mutableExchange = exchange.mutate().request(mutableReq).build();
      return chain.filter(mutableExchange);
    }else{ //如果是登录认证请求，直接执行不需要进行JWT权限验证
      return chain.filter(exchange);
    }
  }

  @Override
  public int getOrder() {
    return 101;
  }
}

自定义过滤器工厂，为网关加载过滤器使用

package com.alibaba.cloud.nacosgatewaysample.Filter;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.stereotype.Component;

@Component
public class JWTAuthCheckFilterFactory extends AbstractGatewayFilterFactory<Object> {
    @Autowired
    JWTAuthCheckFilter jWTAuthCheckFilte;
    @Override
    public GatewayFilter apply(Object config) {
        return jWTAuthCheckFilte;
    }
}

5.2修改Nacos中心nacos-gateway-sample.json断言配置，增加过滤器

[
    {
        "id":"nacos-gateway-sample",   
        "order":0, 
        "predicates":[ 
            {
              "args":{
                  "pattern":"/nacos-discovery-provider-sample/**" 
              },
              "name":"Path"  
              }
        ],
        "uri":"lb://nacos-discovery-provider-sample",
        "filters":[
            {
                "name":"JWTAuthCheckFilterFactory"
            },
            {
               "name":"StripPrefix", 
               "args":{
                    "parts":"1"
               }     
            }
        ]
    }
]

filters的name指定为自定义工厂JWTAuthCheckFilterFactory。

至此鉴权流程完成。

5.3增加模拟登录接口获取token

/**
     * 使用用户名密码换JWT令牌
     */
    @RequestMapping("/authentication")
    public Mono<Map> authentication(@RequestBody Map<String,String> map){
        //从请求体中获取用户名密码
        String username  = map.get(jwtProperties.getUserParamName());
        String password = map.get(jwtProperties.getPwdParamName());

        if(StringUtils.isEmpty(username)
                || StringUtils.isEmpty(password)){
            return buildErrorResponse("用户名或者密码不能为空");
        }
        //根据用户名（用户Id）去数据库查找该用户
        SysUser sysUser =new SysUser();
        sysUser.setPassword("123456");
        if(sysUser != null){
            //将数据库的加密密码与用户明文密码match
          // boolean isAuthenticated = passwordEncoder.matches("123456",sysUser.getPassword());
            boolean isAuthenticated="123456".equals(sysUser.getPassword());
            if(isAuthenticated){ //如果匹配成功
                //通过jwtTokenUtil生成JWT令牌并return
                return buildSuccessResponse(jwtTokenUtil.generateToken(username,null));
            } else{ //如果密码匹配失败
                return buildErrorResponse("请确定您输入的用户名或密码是否正确！");
            }
        }else{
            return buildErrorResponse("请确定您输入的用户名或密码是否正确！");
        }
    }

返回TOKEN之后，测试请求网关/nacos-discovery-provider-sample/call/echo/nnn

请求Header中带入参数

Authorization：eyJhbGciOiJIUzUxMiJ9.eyJleHAiOjMwMDE3MDk3Nzc5NjIsInN1YiI6ImFkbWluIiwiY3JlYXRlZCI6MTcwOTc3Nzk2MjQ1Nn0.3pw5NVIhiMggFvPEDvUHGX_Iy8EyLT0EQGQS7Xf3bAiu5GhAFHvtSd2_3nsOMzjtAbYT2sk2ffx122cLBXQzPQ

接口正常。去掉Authorization，接口返回

{
"msg": "鉴权失败",
"code": "401"
}

四、为服务增加sentinel限流熔断配置

4.1下载按照运行sentinel

下载Sentinel: 官网阿里 Sentinelsentinel

Sentinel: 官网阿里 Sentinel

启动sentinel指定管理界面端口为9092

nohup java -Dserver.port=9090 -Dcsp.sentinel.dashboard.server=localhost:9092 -Dproject.name=sentinel-dashboard -jar sentinel-dashboard-1.8.7.jar &

登录管理端用户名密码默认 sentinel/sentinel

4.2网关服务配置sentinel

application.properties增加

## 整合sentinel，配置sentinel控制台的地址## 指定控制台的地址，默认端口8080
spring.cloud.sentinel.enabled=true

#sentinel控制台
spring.cloud.sentinel.transport.dashboard=192.168.100.115:9090

重启服务,登录sentinel管理端右侧不显示网关服务

idea增加启动参数

Dcsp.sentinel.dashboard.server=192.168.100.115:9090 -Dproject.name=nacos-natewayn-ample -Dcsp.sentinel.api.port=9090 -Dcsp.sentinel.app.type=1

或者启动类增加

重新启动显示正常

正常压测

4.3配置限流规则

本例以路由前缀限流

4.3.1选择API管理，新增API规则

新增API分组

匹配串 /nacos-discovery-provider-sample/**

4.3.2新增网关流控规则

限流配置完成

压测截图

4.3.3配置熔断规则

修改限流规则qps1000，停掉发现服务nacos-discovery-provider-sample测试

返回429 熔断生效

4.3.4配置限流和熔断统一返回值，此例是返回值，

 一种是redirect，重定向跳转，需要同时配置redirect(跳转的uri)

application.properties

spring.cloud.sentinel.scg.fallback.mode=response
## 响应的状态
spring.cloud.sentinel.scg.fallback.response-status=200
## 响应体
spring.cloud.sentinel.scg.fallback.response-body="{\"code\":\"429\",\"msg\":\"请求太多了\"}"
重新启动服务nacos-discovery-provider-sample测试限流返回

返回正常200数据。

五、限流熔断配置Nacos持久化

限流和熔断配置在网关服务重启之后会失效，在sentinel中会消失，改为Nacos持久化配置

引入依赖

<dependency>
<groupId>com.alibaba.csp</groupId>
<artifactId>sentinel-datasource-nacos</artifactId>
</dependency>

5.1Nacos控制台新建一个限流和熔断配置

5.1.1限流配置：

nacos-discovery-provider-sample-flow的json配置，内容如下：

[
  {
    "resource": "nacos-gateway-sample",
    "controlBehavior": 0,
    "count": 100,
    "grade": 1,
    "limitApp": "default",
    "strategy": 0
  }
]

resource：资源名称；和网关的配置nacos-gateway-sample.json id保持一致，指明来源

nacos-gateway-sample

limitApp：来源应用；
grade：阈值类型，0表示线程数，1表示QPS
count：单机阈值；
strategy：流控模式，0表示直接，1表示关联，2表示链路；
controlBehavior：流控效果，0表示快速失败，1表示Warm Up，2表示排队等待；
clusterMode：是否集群。

5.1.1熔断配置

nacos-discovery-provider-sample-degrade

5.2项目配置文件增加nacos的数据源配置

## 整合sentinel，配置sentinel控制台的地址## 指定控制台的地址，默认端口8080
spring.cloud.sentinel.enabled=true
#sentinel控制台
spring.cloud.sentinel.transport.dashboard=192.168.100.115:9090
#指定限流的配置名字
sentinel.config.nacos.data-id-flow=nacos-discovery-provider-sample-flow
#指定熔断的配置名字
sentinel.config.nacos.data-id-degrade=nacos-discovery-provider-sample-degrade
#指定默认分组
sentinel.config.nacos.group=DEFAULT_GROUP

5.3创建config类，初始化加载配置参数属性

package com.alibaba.cloud.nacosgatewaysample.config;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Configuration;
@SuppressWarnings("all")
@Configuration
public class SentinelConfig {

    /**
     * Nacos 服务器地址
     */
    public static String NACOS_SERVER_ADDR;
    /**
     * Nacos 命名空间
     */
    public static String NACOS_SENTINEL_NAMESPACE;
    /**
     * Nacos 分组id
     */
    public static String NACOS_SENTINEL_GROUP;
    /**
     * nacos 限流配置列表中的dataid
     */
    public static String NACOS_SENTINEL_DATAID_FLOW;
    /**
     * nacos 熔断配置列表中的dataid
     */
    public static String NACOS_SENTINEL_DATAID_DEGRADE;

    @Value("${spring.cloud.nacos.discovery.server-addr}")
    public  void setNacosServerAddr(String nacosServerAddr) {
        NACOS_SERVER_ADDR = nacosServerAddr;
    }

    @Value("${spring.cloud.nacos.discovery.namespace}")
    public  void setNacosSentinelNamespace(String nacosSentinelNamespace) {
        NACOS_SENTINEL_NAMESPACE = nacosSentinelNamespace;
    }

    @Value("${sentinel.config.nacos.group}")
    public  void setNacosSentinelGroup(String nacosSentinelGroup) {
        NACOS_SENTINEL_GROUP = nacosSentinelGroup;
    }

    @Value("${sentinel.config.nacos.data-id-flow}")
    public  void setNacosSentinelDataidFlow(String nacosSentinelDataidFlow) {
        NACOS_SENTINEL_DATAID_FLOW = nacosSentinelDataidFlow;
    }
    @Value("${sentinel.config.nacos.data-id-degrade}")

    public  void setNacosSentinelDataidDegrade(String nacosSentinelDataidDegrade) {
        NACOS_SENTINEL_DATAID_DEGRADE = nacosSentinelDataidDegrade;
    }
}

5.4创建限流熔断工厂类，加载sentinel相关内容。加载限流、熔断规则，自定义限流熔断错误返回处理，

限流自定义返回状态码429

熔断自定义返回状态码504

package com.alibaba.cloud.nacosgatewaysample.Filter;

import com.alibaba.cloud.nacosgatewaysample.config.SentinelConfig;
import com.alibaba.csp.sentinel.adapter.gateway.sc.SentinelGatewayFilter;
import com.alibaba.csp.sentinel.adapter.gateway.sc.callback.BlockRequestHandler;
import com.alibaba.csp.sentinel.adapter.gateway.sc.exception.SentinelGatewayBlockExceptionHandler;
import com.alibaba.csp.sentinel.datasource.ReadableDataSource;
import com.alibaba.csp.sentinel.datasource.nacos.NacosDataSource;
import com.alibaba.csp.sentinel.slots.block.degrade.DegradeException;
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.FlowException;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRuleManager;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.alibaba.nacos.api.PropertyKeyConst;
import org.springframework.beans.factory.ObjectProvider;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.DependsOn;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.codec.ServerCodecConfigurer;
import org.springframework.stereotype.Component;
import org.springframework.web.reactive.function.server.ServerResponse;
import org.springframework.web.reactive.result.view.ViewResolver;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import javax.annotation.PostConstruct;
import java.util.*;

@Component
//再另外一个Bean初始化之后再去初始化当前类
@DependsOn({"sentinelConfig"})

//再另外一个Bean初始化之后再去初始化当前类
public class SentinelFactory implements BlockRequestHandler {
    private  List<ViewResolver> viewResolvers;
    private  ServerCodecConfigurer serverCodecConfigurer;
    public SentinelFactory(ObjectProvider<List<ViewResolver>> viewResolversProvider,
                           ServerCodecConfigurer serverCodecConfigurer) {
        //视图解析
        this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
        this.serverCodecConfigurer = serverCodecConfigurer;
        Properties properties = new Properties();
        properties.put(PropertyKeyConst.SERVER_ADDR, SentinelConfig.NACOS_SERVER_ADDR);
        properties.put(PropertyKeyConst.NAMESPACE, SentinelConfig.NACOS_SENTINEL_NAMESPACE);
        //加载nacos配置中心的限流规则
        ReadableDataSource<String, List<FlowRule>> flowRuleDataSource = new NacosDataSource<>
                (properties, SentinelConfig.NACOS_SENTINEL_GROUP, SentinelConfig.NACOS_SENTINEL_DATAID_FLOW,
                        source -> JSON.parseObject(source, new TypeReference<List<FlowRule>>() {
                        }));
        FlowRuleManager.register2Property(flowRuleDataSource.getProperty());

        //加载nacos配置中心的熔断规则
        ReadableDataSource<String, List<DegradeRule>> degradeRuleDataSource = new NacosDataSource<>
                (properties, SentinelConfig.NACOS_SENTINEL_GROUP, SentinelConfig.NACOS_SENTINEL_DATAID_DEGRADE,
                        source -> JSON.parseObject(source, new TypeReference<List<DegradeRule>>() {
                        }));
        DegradeRuleManager.register2Property(degradeRuleDataSource.getProperty());

    }
    //异常处理接收Handler
    @Bean
    @Order(Ordered.HIGHEST_PRECEDENCE)
    public SentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
        return new SentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
    }

    //这是执行sentinel规则的拦截器，Gateway路由之前会先执行这个拦截器
    @Bean
    @Order(Ordered.HIGHEST_PRECEDENCE)
    public GlobalFilter sentinelGatewayFilter() {
        return new SentinelGatewayFilter();
    }

    @Override
    public Mono<ServerResponse> handleRequest(ServerWebExchange serverWebExchange, Throwable throwable) {
        String path = serverWebExchange.getRequest().getPath().pathWithinApplication().value();
        Map map = new HashMap();
        map.put("error","Unauthorized");
        map.put("path",path);
        map.put("status",HttpStatus.TOO_MANY_REQUESTS.value());
        map.put("imestamp",new Date());
        if (throwable instanceof FlowException){
            map.put("message","服务被限流");
            return ServerResponse.status(HttpStatus.TOO_MANY_REQUESTS.value()).contentType(MediaType.APPLICATION_JSON).body(Mono.just(map), Map.class);

        } else if (throwable instanceof DegradeException) {
            map.put("message","服务被熔断降级");
            return ServerResponse.status(HttpStatus.GATEWAY_TIMEOUT.value()).contentType(MediaType.APPLICATION_JSON).body(Mono.just(map), Map.class);
        }
         return ServerResponse.status(HttpStatus.INTERNAL_SERVER_ERROR.value()).contentType(MediaType.APPLICATION_JSON).body(Mono.just(map), Map.class);

    }

}