1 部署
1.1 单节点部署
如果只是想部署一个节点进行测试，则非常简单，只要下载nacos包，也不需要修改任何配置，执行startup.sh脚本即可。如下所示：
% unzip nacos-server-2.2.3.zip
% cd nacos
% ls
LICENSE NOTICE bin conf target
% ls bin conf target
bin:
shutdown.cmd shutdown.sh startup.cmd startup.sh
conf:
1.4.0-ipv6_support-update.sql announcement.conf application.properties application.properties.example cluster.conf.example derby-schema.sql mysql-schema.sql nacos-logback.xml
target:
nacos-server.jar
% ./bin/startup.sh -m standalone
nacos is starting with standalone
nacos is starting，you can check the /nacos/logs/start.out
启动日志默认在logs/start.out文件中，从启动日志可知，服务默认监听的端口为8848，以stand alone模式启动，采用的数据库存储为嵌入式内存数据库。standalone模式下，nacos也只能采用嵌入式数据库。
2023-06-08 15:00:51,383 INFO Tomcat initialized with port(s): 8848 (http)
2023-06-08 15:00:51,505 INFO Root WebApplicationContext: initialization completed in 2258 ms
2023-06-08 15:00:56,018 INFO Adding welcome page: class path resource [static/index.html]
2023-06-08 15:00:56,378 WARN You are asking Spring Security to ignore Ant [pattern='/**']. This is not recommended -- please use permitAll via HttpSecurity#authorizeHttpRequests instead.
2023-06-08 15:00:56,379 INFO Will not secure Ant [pattern='/**']
2023-06-08 15:00:56,397 INFO Will secure any request with [org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter@4a9cc6cb, org.springframework.security.web.context.SecurityContextPersistenceFilter@21526f6c, org.springframework.security.web.header.HeaderWriterFilter@cdc3aae, org.springframework.security.web.csrf.CsrfFilter@3f19b8b3, org.springframework.security.web.authentication.logout.LogoutFilter@517bd097, org.springframework.security.web.savedrequest.RequestCacheAwareFilter@299266e2, org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter@66ea1466, org.springframework.security.web.authentication.AnonymousAuthenticationFilter@5990e6c5, org.springframework.security.web.session.SessionManagementFilter@5dcbb60, org.springframework.security.web.access.ExceptionTranslationFilter@a486d78]
2023-06-08 15:00:56,417 INFO Exposing 1 endpoint(s) beneath base path '/actuator'
2023-06-08 15:00:56,454 INFO Tomcat started on port(s): 8848 (http) with context path '/nacos'
2023-06-08 15:00:56,470 INFO Nacos started successfully in stand alone mode. use embedded storage
从启动日志也可知，通过以下地址可以登录nacos web管理页面：
http://127.0.0.1:8848/nacos
如果你只想使用nacos的服务注册和发现以及服务管理的功能，可以通过参数指定，如下所示：
% ./bin/startup.sh -m standalone -f naming
或者你只想使用nacos的配置管理的功能，也可以通过参数指定，如下所示：
% ./bin/startup.sh -m standalone -f config
关闭nacos服务：
% ./bin/shutdown.sh
The nacosServer(51598) is running...
Send shutdown request to nacosServer(51598) OK
1.2 集群部署
如果想在生产环境中使用，需采用集群方式部署，集群部署时，一般采用外部数据库。
1.2.1 准备数据库
我这里的外部数据库采用mysql，版本为8.x，如下初始化mysql的数据库和表
mysql> select version();
+-----------+
| version() |
+-----------+
| 8.0.33 |
+-----------+
1 row in set (0.00 sec)
mysql> CREATE DATABASE IF NOT EXISTS nacos DEFAULT CHARSET utf8mb4 COLLATE utf8mb4_unicode_ci;
mysql> use nacos;
mysql> source ./conf/mysql-schema.sql;
mysql> show tables;
+----------------------+
| Tables_in_nacos |
+----------------------+
| config_info |
| config_info_aggr |
| config_info_beta |
| config_info_tag |
| config_tags_relation |
| group_capacity |
| his_config_info |
| permissions |
| roles |
| tenant_capacity |
| tenant_info |
| users |
+----------------------+
12 rows in set (0.00 sec)
1.2.2 准备配置文件
由于nacos使用了raft协议来同步集群内节点的数据，所以集群模式时需要三个以上的节点，且节点数最好是单数。我这里在单机启动三个nacos实例来搭建一个三节点测试集群，三个实例的端口号分别为8847、8848、8849。
修改配置文件conf/application.properties内容如下：
### Default web context path:
server.servlet.contextPath=/nacos
### Include message field
server.error.include-message=ALWAYS
### Default web server port:
server.port=8847
### Deprecated configuration property, it is recommended to use `spring.sql.init.platform` replaced.
# spring.datasource.platform=mysql
spring.sql.init.platform=mysql
### Count of DB:
db.num=1
### Connect URL of DB:
db.url.0=jdbc:mysql://127.0.0.1:3306/nacos?characterEncoding=utf8&connectTimeout=1000&socketTimeout=3000&autoReconnect=true&useUnicode=true&useSSL=false&serverTimezone=Asia/Shanghai&zeroDateTimeBehavior=convertToNull&failOverReadOnly=false&allowMultiQueries=true&rewriteBatchedStatements=true
db.user.0=root
db.password.0=mysql123@Sys
### Connection pool configuration: hikariCP
db.pool.config.connectionTimeout=30000
db.pool.config.validationTimeout=10000
db.pool.config.maximumPoolSize=20
db.pool.config.minimumIdle=2
这里需要注意的是，配置文件中的spring.datasource.platform=mysql和spring.sql.init.platform=mysql配置默认是注释掉的，需要打开一个，否则启动时会报dataSource or tableName is null错误：
Caused by: com.alibaba.nacos.api.exception.NacosException: Nacos Server did not start because dumpservice bean construction failure :
errCode: 102, errMsg: dataSource or tableName is null
at com.alibaba.nacos.config.server.service.dump.DumpService.dumpOperate(DumpService.java:260)
at com.alibaba.nacos.config.server.service.dump.ExternalDumpService.init(ExternalDumpService.java:61)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:389)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:333)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:157)
... 54 common frames omitted
Caused by: com.alibaba.nacos.api.exception.runtime.NacosRuntimeException: errCode: 102, errMsg: dataSource or tableName is null
at com.alibaba.nacos.plugin.datasource.MapperManager.findMapper(MapperManager.java:102)
at com.alibaba.nacos.config.server.service.repository.extrnal.ExternalConfigInfoPersistServiceImpl.findConfigMaxId(ExternalConfigInfoPersistServiceImpl.java:628)
at com.alibaba.nacos.config.server.service.dump.processor.DumpAllProcessor.process(DumpAllProcessor.java:51)
at com.alibaba.nacos.config.server.service.dump.DumpService.dumpConfigInfo(DumpService.java:317)
at com.alibaba.nacos.config.server.service.dump.DumpService.dumpOperate(DumpService.java:230)
... 62 common frames omitted
创建一个集群配置文件conf/cluster.conf，里面指定加入集群的节点列表，内容如下：
127.0.0.1:8847
127.0.0.1:8848
127.0.0.1:8849
1.2.3 启动集群
逐次启动集群所有节点，观察启动日志，如下表示启动成功。
2023-06-07 17:14:43,622 INFO The server IP list of Nacos is [127.0.0.1:8847, 127.0.0.1:8848, 127.0.0.1:8849, 172.18.186.84:8847]
2023-06-07 17:14:44,628 INFO Nacos is starting...
2023-06-07 17:14:53,702 INFO Nacos started successfully in cluster mode. use external storage
2 服务注册、发现与管理
2.1 服务注册
如果是java开发者，在spring boot、spring cloud加持下，服务提供者想向nacos注册自己，只需要添加几项简单配置和注解即可。
pom.xml文件中添加nacos的相关依赖：
<!-- https://mvnrepository.com/artifact/com.alibaba.cloud/spring-cloud-starter-alibaba-nacos-discovery -->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
<version>2022.0.0.0-RC2</version>
</dependency>
bootstrap.yml配置文件中添加nacos服务的地址：
spring:
cloud:
nacos:
discovery:
server-addr: "127.0.0.1:8848"
然后添加注解@EnableDiscoveryClient
@EnableDiscoveryClient
@SpringBootApplication
public class NacosClientProviderApplication {
public static void main(String[] args) {
SpringApplication.run(NacosClientProviderApplication.class, args);
}
}
启动服务后，就可以在nacos web管理页面看到注册的服务了:
假设服务提供者提供了以下服务，我们后续通过nacos发现服务后调用它：
@Slf4j
@RestController
@RequestMapping("/service")
public class ServiceController {
@GetMapping("/hello")
public String hello() {
log.info("==============Hello ServiceController");
return "hello";
}
}
2.2 服务发现和调用
服务调用者通过nacos发现服务和调用服务，与服务提供者一样添加相同的依赖和配置即可：
pom.xml文件中添加nacos的相关依赖：
<!-- https://mvnrepository.com/artifact/com.alibaba.cloud/spring-cloud-starter-alibaba-nacos-discovery -->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
<version>2022.0.0.0-RC2</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-loadbalancer</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
bootstrap.yml配置文件中添加nacos服务的地址：
spring:
cloud:
nacos:
discovery:
server-addr: "127.0.0.1:8848"
然后添加注解@EnableDiscoveryClient
@EnableFeignClients
@EnableDiscoveryClient
@SpringBootApplication
public class NacosClientProviderApplication {
public static void main(String[] args) {
SpringApplication.run(NacosClientProviderApplication.class, args);
}
}
使用openfeign即可调用服务提供者的服务：
@FeignClient(name = "nacos-client-provider", path = "/service")
public interface ServiceFeign {
@GetMapping("/hello")
String hello();
}
3 配置管理
跟服务注册和发现类似，pom.xml中添加相应的依赖：
<!-- https://mvnrepository.com/artifact/com.alibaba.cloud/spring-cloud-starter-alibaba-nacos-discovery -->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
<version>${nacos.version}</version>
</dependency>
bootstrap.yml配置文件中添加相应的配置：
spring:
cloud:
nacos:
config:
server-addr: "127.0.0.1:8848"
# nacos中维护的配置文件的格式
file-extension: yml
import-check:
# 关闭检查时，即使nacos中没有该服务的任何配置，也能正常启动。
enabled: false
然后就可以在nacos web配置管理页面添加服务的配置了（服务默认会向nacos获取${服务名}.yml和${服务名}-${active-profile}.yml文件的配置），如下新增配置，跟我们编写本地配置文件是一样的。
服务通过@ConfigurationProperties("app")注解获取nacos的配置，
@Data
@AllArgsConstructor
@NoArgsConstructor
@Component
@ConfigurationProperties("app")
public class NacosConfig {
private String helloContent;
}
或通过@Value获取nacos的配置（不过通过@Value注解获取配置，如果需要动态更新，还需要在相应类上添加@RefreshScope注解），就获取本地配置一样
@Data
@AllArgsConstructor
@NoArgsConstructor
@Component
@RefreshScope
public class NacosConfig {
@Value("${app.hello-content}")
private String helloContent;
}
nacos上的配置发布后，相应服务的配置项的值也立即发生了变化。同理，修改nacos上的配置发布后，相应服务配置项的值也立即更新了。
