nacos 服务发现失败的问题

学习nacos时按教程走发现nacos发现不了服务

先查网上的资料发现基本都是说缺少依赖的

需要3个依赖

            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.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>
 
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>

检查发现没有缺少依赖

后面查找发现是依赖版本不对，spring-cloud-alibaba-dependencies在spring cloud官网上的最新版本不匹配spring boot 和 spring cloud的最新版本，解决方案俩种

1：spring boot 和 spring cloud换成低版本，附可用版本一份

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <packaging>pom</packaging>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.6</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>net.biancheng.c</groupId>
    <artifactId>spring-cloud-alibaba-demo</artifactId>
    <version>1.0-SNAPSHOT</version>
 
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <junit.version>4.12</junit.version>
        <log4j.version>1.2.17</log4j.version>
        <lombok.version>1.16.18</lombok.version>
        <spring-cloud.version>2020.0.4</spring-cloud.version>
    </properties>
    <dependencyManagement>
        <dependencies>
            <!--Spring Cloud Alibaba 的版本信息-->
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2021.1</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--Spring Cloud 的版本信息-->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

2：找了下spring-cloud-alibaba-dependencies的版本，找到有个2022.0.0.0-RC1的版本，试了下可行，同样附可用版本​​​​​​

<?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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.0.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
  
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>
    <description>huangMeng_springCload</description>
 
 
    <properties>
        <java.version>17</java.version>
        <spring-cloud.version>2022.0.1</spring-cloud.version>
        <spring-cloud-alibaba.version>2022.0.0.0-RC1</spring-cloud-alibaba.version>
    </properties>
 
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.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>
 
 
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter</artifactId>
            </dependency>
        </dependencies>
    </dependencyManagement>
 
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
 
</project>

因为是学习我使用的是第二种方法。

修改后发送请求时发现@LoadBalanced注解拦截失效了，查找了其他文章发现

由于 Ribbon 已经停更，2020Spring Cloud 在 Hoxton.M2 Released 版本将 Ribbon 剔除，并使用 Spring Cloud Loadbalancer 作为其替代品；

解决方法另外导入LoadBalanced的依赖

 
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-loadbalancer</artifactId>
                <version>4.0.1</version>
            </dependency>

既然没有使用ribbon，负载均衡策略的配置也不太一样了，不能直接在yml配置文件配置了，已配置nacos的负载均衡策略为例，添加注解在RestConfig上指定对应配置就行，@LoadBalanced还是需要不要去掉

@LoadBalancerClient(value = "huangmeng-user", configuration = NacosLoadBalancerClientConfiguration.class)

NacosLoadBalancerClientConfiguration是nacos库里面写好了的配置，配置其他策略就自己写配置文件就好了例如：

@Configuration
public class CustomLoadBalancerConfiguration {
 
    // 参考 NacosLoadBalancerClientConfiguration
    @Bean
    public ReactorLoadBalancer<ServiceInstance> roundRobinLoadBalancer(Environment environment, LoadBalancerClientFactory loadBalancerClientFactory) {
        String name = environment.getProperty(LoadBalancerClientFactory.PROPERTY_NAME);
 
        return new RoundRobinLoadBalancer(loadBalancerClientFactory.getLazyProvider(name, ServiceInstanceListSupplier.class), name);
    }
 
}

@Configuration加了是全局配置，不加这是按LoadBalancerClient 或者LoadBalancerClients配置的来

之后整合gateway也出现问题访问不了，解决方法像之前一样导入loadbalance的依赖就好了

解决后至少暂时没问题了，只能我看的这个教程时效性有点差