Nacos Spring Boot Project

Alibaba Nacos ships main core features of Cloud-Native application, including:

• Service Discovery and Service Health Check
• Dynamic Configuration Management
• Dynamic DNS Service
• Service and MetaData Management

Nacos Spring Boot Project is based on it and embraces Spring Boot ECO System so that developers could build Spring Boot application rapidly.

Nacos Spring Boot Project consist of two parts: nacos-config-spring-boot and nacos-discovery-spring-boot.

nacos-config-spring-boot module is using for Dynamic Configuration Management and Service and MetaData Management.

nacos-discovery-spring-boot module is using for Service Discovery, Service Health Check and Dynamic DNS Service.

Demos

• Nacos Config Simple Demo

• Nacos Discovery Simple Demo

Dependencies & Compatibility

master branch

Dependencies	Compatibility
Java	1.8+
Spring Boot	2.0.3.RELEASE

1.x branch

Dependencies	Compatibility
Java	1.7+
Spring Boot	1.4.1.RELEASE

Quick Start

Nacos Config

First, you have to start a Nacos Server in backend , If you don't know steps, you can learn about quick start.

Suppose your Nacos Server is startup, you would add nacos-config-spring-boot-starter in your Spring application's dependencies :

    <dependencies>
        ...
        
        <dependency>
            <groupId>com.alibaba.boot</groupId>
            <artifactId>nacos-config-spring-boot-starter</artifactId>
            <version>${latest.version}</version>
        </dependency>
        
        ...
    </dependencies>

After that, you could define some configurations in application.properties:

nacos.config.server-addr=localhost

nacos.config.server-addr attribute configures "${host}:${port}" of your Nacos Server

Then you could using @SpringBootApplication to annotate main class like normal SpringBoot Application and startup:

@SpringBootApplication
public class ConfigApplication {
    public static void main(String[] args) {
        SpringApplication.run(ConfigApplication.class, args);
    }
}

If you'd like to use "Distributed Configuration" features, ConfigService is a core service interface to get or publish config, you could use "Dependency Injection" to inject ConfigService instance in your Spring Beans.

@Service
public class ConfigServiceDemo {

    @NacosInjected
    private ConfigService configService;
    
    public void demoGetConfig() {
        try {
            String dataId = "{dataId}";
            String group = "{group}";
            String content = configService.getConfig(dataId, groupId, 5000);
        	System.out.println(content);
        } catch (NacosException e) {
            e.printStackTrace();
        }
    }
    ...
}

above code equals below one:

try {
    // Initialize the configuration service, and the console automatically obtains the following parameters through the sample code.
    String serverAddr = "{serverAddr}";
    String dataId = "{dataId}";
    String group = "{group}";
    Properties properties = new Properties();
    properties.put("serverAddr", serverAddr);
    ConfigService configService = NacosFactory.createConfigService(properties);
    // Actively get the configuration.
    String content = configService.getConfig(dataId, group, 5000);
    System.out.println(content);
} catch (NacosException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

Nacos Discovery

First, you have to start a Nacos Server in backend , If you don't know steps, you can learn about quick start.

Suppose your Nacos Server is startup, you would add nacos-discovery-spring-boot-starter in your Spring application's dependencies :

    <dependencies>
        ...
        
        <dependency>
            <groupId>com.alibaba.boot</groupId>
            <artifactId>nacos-discovery-spring-boot-starter</artifactId>
            <version>${latest.version}</version>
        </dependency>
        
        ...
    </dependencies>

After that, you could define some configurations in application.properties:

nacos.discovery.server-addr=localhost

nacos.discovery.server-addr attribute configures "${host}:${port}" of your Nacos Server

Then you could using @SpringBootApplication to annotate main class like normal SpringBoot Application and startup:

@SpringBootApplication
public class DiscoveryApplication {
    public static void main(String[] args) {
        SpringApplication.run(DiscoveryApplication.class, args);
    }
}

If you'd like to use "Service Registry" features, NamingService is a core service interface to get or publish config, you could use "Dependency Injection" to inject NamingService instance in your Spring Beans.

@Service
public class NamingServiceDemo {

    @NacosInjected
    private NamingService namingService;
    
    public void demoRegisterService() {
        try {
            namingService.registerInstance("test-service", "1.1.1.1", 8080);
        } catch (NacosException e) {
            e.printStackTrace();
        }
    }
    ...
}

above code equals below one:

try {
    // Initialize the naming service, and the console automatically obtains the following parameters through the sample code.
    String serverAddr = "{serverAddr}";
    Properties properties = new Properties();
    properties.put("serverAddr", serverAddr);
    NamingService naming = NamingFactory.createNamingService(properties);
    namingService.registerInstance("test-service", "1.1.1.1", 8080);
} catch (NacosException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

For more information about Nacos Spring, see Nacos Spring Project.

Endpoint

Nacos config starter and Nacos discovery starter also support the implementation of Spring Boot actuator endpoints.

Prerequisite:

Add dependency spring-boot-starter-actuator to your pom.xml file, and configure your endpoint security strategy.

• Spring Boot1.x: Add configuration

management.security.enabled=false

• Spring Boot2.x: Add configuration

management.endpoints.web.exposure.include=*

To view the endpoint information, visit the following URLS:

Nacos Config:

• Spring Boot1.x: Sentinel Endpoint URL is http://127.0.0.1:10011/nacos-config.
• Spring Boot2.x: Sentinel Endpoint URL is http://127.0.0.1:10011/actuator/nacos-config.

Nacos Discovery:

• Spring Boot1.x: Sentinel Endpoint URL is http://127.0.0.1:10012/nacos-discovery.
• Spring Boot2.x: Sentinel Endpoint URL is http://127.0.0.1:10012/actuator/nacos-discovery.

Health Checks

nacos-config-spring-boot-actuator and nacos-discovery-spring-boot-actuator support the standard Spring Boot HealthIndicator as a production-ready feature , which will be aggregated into Spring Boot's Health and exported on HealthEndpoint that works MVC (Spring Web MVC) and JMX (Java Management Extensions) both if they are available.

Suppose a Spring Boot Web application did not specify management.server.port, you can access http://localhost:{port}/actuator/health via Web Client and will get a response with JSON format is like below :

Nacos Config:

{
"status": "UP",
"details": {
    "nacosConfig": {
        "status": "UP"
    },
    "diskSpace": {
        "status": "UP",
        "details": {
            "total": 250140434432,
            "free": 52323512320,
            "threshold": 10485760
        }
    }
}
}

Nacos Discovery:

{
"status": "UP",
"details": {
    "nacosDiscovery": {
        "status": "UP"
    },
    "diskSpace": {
        "status": "UP",
        "details": {
            "total": 250140434432,
            "free": 52323680256,
            "threshold": 10485760
        }
    }
}
}

For more information about Nacos Spring, see Nacos Spring Project.

Relative Projects

• Alibaba Nacos
• Alibaba Spring Context Support
• Nacos Spring Project
• Nacos Spring Cloud Project