Nacos Config集成SpringCloud使用说明

	<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
			<version>0.2.1.RELEASE</version>
	</dependency>

#nacos配置中心地址
spring.cloud.nacos.config.server-addr=10.136.15.122:8848
#默认应用名称，配置中心中data-id 默认为name+file-extension
spring.application.name=example
没有配置情况下用name作为前缀
#spring.cloud.nacos.config.prefix
#应用文件格式支持properties,yml两种
spring.cloud.nacos.config.file-extension=properties

package com.nacos;


import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/config")
@RefreshScope
public class ConfigController {

    @Value("${useLocalCache:false}")
    private boolean useLocalCache;
    
    /**
     * http://localhost:8080/config/get
     */
    @RequestMapping("/get")
    public boolean get() {
        return useLocalCache;
    }
}

package com.nacos;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;


@SpringBootApplication
public class NacosConfigApplication {

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

#配置中心地址
spring.cloud.nacos.config.server-addr=10.136.15.122:8848

#应用名称，非必须，如果没有配置prefix，默认以name为前缀
#spring.application.name=example
#data-id前缀
spring.cloud.nacos.config.prefix=example
#文件类型，支持properties和yml两种数据格式
spring.cloud.nacos.config.file-extension=properties
#环境，可以隔离不同配置环境之间的配置，如dev,uat,pro
spring.profiles.active=dev
#命名空间 也是起隔离作用的，隔离不同应用这之间的作用
spring.cloud.nacos.config.namespace=c04b0cdf-91c7-470a-b6a9-423da6cc7a2b

#分组起隔离同一命名空间下，不同的分组
spring.cloud.nacos.config.group=test

#加载额外配置，除加载上面主配置文件外，额外加载的公有配置功能
spring.cloud.nacos.config.ext-config[0].data-id=test.properties
spring.cloud.nacos.config.ext-config[0].refresh=true

public void initialize(ConfigurableApplicationContext applicationContext) {
		CompositePropertySource composite = new CompositePropertySource(
				BOOTSTRAP_PROPERTY_SOURCE_NAME);
		AnnotationAwareOrderComparator.sort(this.propertySourceLocators);
		boolean empty = true;
		ConfigurableEnvironment environment = applicationContext.getEnvironment();
		for (PropertySourceLocator locator : this.propertySourceLocators) {
			PropertySource<?> source = null;
			source = locator.locate(environment);
			if (source == null) {
				continue;
			}
			logger.info("Located property source: " + source);
			composite.addPropertySource(source);
			empty = false;
		}
		if (!empty) {
			MutablePropertySources propertySources = environment.getPropertySources();
			String logConfig = environment.resolvePlaceholders("${logging.config:}");
			LogFile logFile = LogFile.get(environment);
			if (propertySources.contains(BOOTSTRAP_PROPERTY_SOURCE_NAME)) {
				propertySources.remove(BOOTSTRAP_PROPERTY_SOURCE_NAME);
			}
			insertPropertySources(propertySources, composite);
			reinitializeLoggingSystem(environment, logConfig, logFile);
			setLogLevels(applicationContext, environment);
			handleIncludedProfiles(environment);
		}
}

public PropertySource<?> locate(Environment env) {

		ConfigService configService = nacosConfigProperties.configServiceInstance();

		if (null == configService) {
			LOGGER.warn(
					"no instance of config service found, can't load config from nacos");
			return null;
		}
		long timeout = nacosConfigProperties.getTimeout();
		nacosPropertySourceBuilder = new NacosPropertySourceBuilder(configService,
				timeout);
		String name = nacosConfigProperties.getName();
       /*配置的分组*/
		String nacosGroup = nacosConfigProperties.getGroup();
        /*配置的前缀*/
		String dataIdPrefix = nacosConfigProperties.getPrefix();
		if (StringUtils.isEmpty(dataIdPrefix)) {
			dataIdPrefix = name;
		}

        /*前缀没有，则取spring.application.name*/
		if (StringUtils.isEmpty(dataIdPrefix)) {
			dataIdPrefix = env.getProperty("spring.application.name");
		}

		List<String> profiles = Arrays.asList(env.getActiveProfiles());
		nacosConfigProperties.setActiveProfiles(profiles.toArray(new String[0]));

		String fileExtension = nacosConfigProperties.getFileExtension();

		CompositePropertySource composite = new CompositePropertySource(
				NACOS_PROPERTY_SOURCE_NAME);
        
		loadSharedConfiguration(composite);
		loadExtConfiguration(composite);
		/*加载配置方法*/
        loadApplicationConfiguration(composite, nacosGroup, dataIdPrefix, fileExtension);

		return composite;
}

private void loadApplicationConfiguration(
			CompositePropertySource compositePropertySource, String nacosGroup,
			String dataIdPrefix, String fileExtension) {
		loadNacosDataIfPresent(compositePropertySource,
				dataIdPrefix + DOT + fileExtension, nacosGroup, fileExtension, true);
		for (String profile : nacosConfigProperties.getActiveProfiles()) {
			String dataId = dataIdPrefix + SEP1 + profile + DOT + fileExtension;
			loadNacosDataIfPresent(compositePropertySource, dataId, nacosGroup,
					fileExtension, true);
		}
}

	private void loadNacosDataIfPresent(final CompositePropertySource composite,
			final String dataId, final String group, String fileExtension,
			boolean isRefreshable) {
		if (NacosContextRefresher.loadCount.get() != 0) {
			NacosPropertySource ps;
			if (!isRefreshable) {
				ps = NacosPropertySourceRepository.getNacosPropertySource(dataId);
			}
			else {
				ps = nacosPropertySourceBuilder.build(dataId, group, fileExtension, true);
			}

			composite.addFirstPropertySource(ps);
		}
		else {
			NacosPropertySource ps = nacosPropertySourceBuilder.build(dataId, group,
					fileExtension, isRefreshable);
			composite.addFirstPropertySource(ps);
		}
	}