In non-spring boot programs, use spring cloud config client

Spring cloud config can centrally manage configuration files, and different (spring-boot) applications can be used like a simple configuration; but it takes a lot of trouble for ordinary spring web applications to use config client;

Reference: https://github.com/spring-cloud/spring-cloud-config/issues/299

Highlights:

Well the "normal" way is to use Spring Cloud Config as part of a Spring Boot app. You really should consider doing that at some point.

If you want to try and cobble it together yourself you need a ConfigServicePropertySourceLocatorand you need to apply it to the Environment before the application context is started. How you do that will depend a lot on how you are creating the ApplicationContext (SpringApplication from Spring Boot would be much easier than whatever you are doing probably).

 

We are a spring web application, and the following methods are only valid for web apps;

1. maven subscription spring cloud config client:

 <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-config-client -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-config-client</artifactId>
            <version>1.2.0.RELEASE</version>
        </dependency>

2. Configure web.xml to let the spring context loader use the customized context;

    <context-param>
        <param-name>contextClass</param-name>
        <param-value>com.me.MyConfigurableWebApplicationContext</param-value>
    </context-param>

3. Implement MyConfigurableWebApplicationContext, the main function is to use a custom environment;

public class MyConfigurableWebApplicationContext extends XmlWebApplicationContext {


    @Override
    protected ConfigurableEnvironment createEnvironment() {
        return new CloudEnvironment();
    }
}

4. Implementing the CloundEnvironment

public class CloudEnvironment extends StandardServletEnvironment {

    @Override
    protected void customizePropertySources(MutablePropertySources propertySources) {
        super.customizePropertySources(propertySources);
        try {
            propertySources.addLast(initConfigServicePropertySourceLocator(this));
        } catch (Exception ex) {
            logger.warn("failed to initialize cloud config environment", ex);
        }
    }

    private PropertySource<?> initConfigServicePropertySourceLocator(Environment environment) {
        ConfigClientProperties configClientProperties = new ConfigClientProperties(environment);
        configClientProperties.setUri("http://localhost:8888");
        configClientProperties.setName("myapp");
        configClientProperties.setLabel("master");
        ConfigServicePropertySourceLocator configServicePropertySourceLocator =
            new ConfigServicePropertySourceLocator(configClientProperties);
        return configServicePropertySourceLocator.locate(environment);
    }

}

5. Test, configure cloud.config=true on the server side, if it works, then you should be able to get true here;

    @Value("${cloud.config: false}")
    public void setCloudConfig(boolean cloudConfig) {
        this.cloudConfig = cloudConfig;
    }