本文受阿里开源的Nacos启发,应用启动后从Nacos服务加载配置到应用中,想着本地开发的时候加载配置能否从本地存储中加载,这样也能加快开发效率
首先
我们来看下SpringCloud项目应用Nacos服务的bootstrap.yaml配置如下
class="java">spring:
cloud:
nacos:
config:
server-addr: 127.0.0.1:8848
file-extension: yaml
discovery:
server-addr: 127.0.0.1:8848
application:
name: demo
profiles:
active: db,redis,rabbit,es,zk
然后在Nacos控制台加配置
经过如上之后,这样应用就能从Nacos取配置。
问题点
笔者认为这里开发的时候如果能从文件系统中加载配置替代Nacos,能加快开发效率,也能心情舒畅的Coding业务代码了。
解决思路
分析
经过分析启动配置spring.factories和配置类NacosConfigProperties
org.springframework.cloud.bootstrap.BootstrapConfiguration=\
org.springframework.cloud.alibaba.nacos.NacosConfigBootstrapConfiguration
找到NacosConfigBootstrapConfiguration 代码如下
@Configuration
@ConditionalOnProperty(name = "spring.cloud.nacos.config.enabled", matchIfMissing = true)
public class NacosConfigBootstrapConfiguration {
@Bean
@ConditionalOnMissingBean
public NacosConfigProperties nacosConfigProperties() {
return new NacosConfigProperties();
}
@Bean
public NacosPropertySourceLocator nacosPropertySourceLocator(
NacosConfigProperties nacosConfigProperties) {
return new NacosPropertySourceLocator(nacosConfigProperties);
}
}
里面关键是NacosPropertySourceLocator实现的
接口PropertySourceLocator
/**
* Strategy for locating (possibly remote) property sources for the Environment.
* Implementations should not fail unless they intend to prevent the application from
* starting.
*
* @author Dave Syer
*
*/
public interface PropertySourceLocator {
/**
* @param environment The current Environment.
* @return A PropertySource, or null if there is none.
* @throws IllegalStateException if there is a fail-fast condition.
*/
PropertySource<?> locate(Environment environment);
}
到了这里就明白怎么做了。
实现
定义自己的应用启动配置类MyLocalConfigBootstrapConfiguration
@Configuration
@ConditionalOnProperty(name = "spring.cloud.nacos.config.enabled", havingValue = "false")
public class MyLocalConfigBootstrapConfiguration {
@Bean
public MyLocalPropertySourceLocator fyLocalPropertySourceLocator() {
return new MyLocalPropertySourceLocator();
}
}
定义META-INF/spring.factories
org.springframework.cloud.bootstrap.BootstrapConfiguration=\
com.liyghting.core.MyLocalConfigBootstrapConfiguration
定义自己的配置加载器MyLocalPropertySourceLocator
@Order(0)
public class MyLocalPropertySourceLocator implements PropertySourceLocator {
private static final Logger LOGGER = LoggerFactory
.getLogger(MyLocalPropertySourceLocator.class);
private static final String MYLOCAL_PROPERTY_SOURCE_NAME = "MYLOCAL";
@Override
public PropertySource<?> locate(Environment environment) {
CompositePropertySource composite = new CompositePropertySource(
MYLOCAL_PROPERTY_SOURCE_NAME);
String dataIdPrefix = environment.getProperty("spring.application.name");
String fileExtension = ".yaml";
PropertySourceLoader propertySourceLoader = new YamlPropertySourceLoader();
URL baseClassesUrl = this.getClass().getClassLoader().getResource("");
File baseClassesFile = new File(baseClassesUrl.getFile());
String basePath = baseClassesFile.getParentFile().getParentFile().getAbsolutePath();
Resource resource = new FileSystemResource(basePath + "/config/" + dataIdPrefix + fileExtension);
try {
composite.addFirstPropertySource(propertySourceLoader.load(dataIdPrefix + fileExtension, resource).get(0));
} catch (IOException e) {
LOGGER.warn("can not load property source {}, exception: {}", dataIdPrefix + fileExtension, e);
}
for (String activeProfile : environment.getActiveProfiles()) {
try {
resource = resource.createRelative(dataIdPrefix + "-" + activeProfile + fileExtension);
composite.addFirstPropertySource(propertySourceLoader.load(dataIdPrefix + "-" + activeProfile + fileExtension, resource).get(0));
} catch (IOException e) {
LOGGER.warn("can not load property source {}, exception: {}", dataIdPrefix + "-" + activeProfile + fileExtension, e);
}
}
return composite;
}
}
版本信息spring-boot 2.1.6.RELEASE
spring-cloud Greenwich.SR2
spring-cloud-alibaba 0.9.0.RELEASE
具体请看我
分享的git库
新的bootstarp.yaml配置如下
spring:
cloud:
nacos:
config:
enabled: false
server-addr: 127.0.0.1:8848
file-extension: yaml
discovery:
server-addr: 127.0.0.1:8848
application:
name: demo
profiles:
active: db,redis,rabbit,es,zk
这样应用启动配置能从本地文件系统加载或Nacos服务加载