@[TOC](Spring Cloud Alibaba 从零搭建(一) —NACOS配置中心)
前言
整体入口：
https://blog.csdn.net/lwb314/article/details/108277732
快速搭建
- 构建工具地址:http://start.aliyun.com
因为是从头开始搭建，所以我们要先做配置，只引入一个
nacos config
POM.XML配置
pom.xml是自动生成就可以这里贴出来如下：
<?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.lwb.demo</groupId>
<artifactId>dubbo-test</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>dubbo-test</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>2.3.7.RELEASE</spring-boot.version>
<spring-cloud-alibaba.version>2.2.2.RELEASE</spring-cloud-alibaba.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</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>2.3.7.RELEASE</version>
<configuration>
<mainClass>com.lwb.demo.dubbotest.DubboTestApplication</mainClass>
</configuration>
<executions>
<execution>
<id>repackage</id>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
启动类
package com.lwb.demo.dubbotest;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class DubboTestApplication {
public static void main(String[] args) {
SpringApplication.run(DubboTestApplication.class, args);
}
}
开始使用NACOS
1.创建文件bootstrap.yml，之前的bootstrap.properties和application.properties都删除，yml比是比properties新的配置格式，有一些新的用法，后续用到会介绍。
这里为什么创建的是bootstrap.yml，而不是application.yml，因为bootstrap是在spring boot框架加载前进行加载的，而spring boot以及后续的dubbo配置都直接使用nacos了，所以配置中心的地址等信息要写在bootstrap.yml配置里
2.直接启动主函数看报错
问题1:
提示配置没生效，因为我们还什么都没配
2021-08-13 13:57:16.334 ERROR 2240 --- [ main] c.a.n.c.config.http.ServerHttpAgent : [NACOS SocketTimeoutException httpGet] currentServerAddr:http://localhost:8848， err : connect timed out
2021-08-13 13:57:16.334 ERROR 2240 --- [ main] c.a.n.c.config.http.ServerHttpAgent : no available server
2021-08-13 13:57:16.341 ERROR 2240 --- [ main] c.a.n.client.config.impl.ClientWorker : [fixed-localhost_8848] [sub-server] get server config exception, dataId=null.properties, group=DEFAULT_GROUP, tenant=
java.net.ConnectException: no available server
问题1从日志上看连的是localhost:8848，而实际我的服务在服务器上，所以先添加nacos配置中心的配置。
spring:
cloud:
nacos:
config:
server-addr: 10.10.10.230:8848
问题2：
2021-08-13 14:07:35.799 INFO 14316 --- [ main] c.a.nacos.client.config.impl.CacheData : [fixed-10.10.10.230_8848] [add-listener] ok, tenant=, dataId=null.properties, group=DEFAULT_GROUP, cnt=1
报错2：
提示没有spring.application.name，那么我们配一下
java.lang.IllegalArgumentException: Could not resolve placeholder 'spring.application.name' in value "${spring.application.name}"
解决方式，加入配置
spring:
application:
name: dubbo_test_demo
报错3：
明显提示程序再注册我本地的8848端口，但是nacos是在服务器上，所以继续添加配置
com.alibaba.nacos.api.exception.NacosException: failed to req API:/nacos/v1/ns/instance/list after all servers([localhost:8848])