PropertyPlaceholderConfigurer读取配置改造SpringBoot集成apollo, 读取不到配置

末蓝、 2024-04-18 21:33 69阅读 0赞

问题描述: Maven多模块开发, SSM框架改造成SpringBoot框架, 集成apollo时,读取不到apollo的配置.

因为是自己封装了PropertyPlaceholderConfigurer进行配置文件的读取:

/**
     *获取到当前架包中资源文件夹下的Properties配置文件
     */
    public class PropertyConfigurer extends PropertyPlaceholderConfigurer {
    
    	private static Map<String,String> ctxPropMap;
    
    	@Override
    	protected void processProperties(ConfigurableListableBeanFactory beanFactoryToProcess, Properties props) throws BeansException {
    		super.processProperties(beanFactoryToProcess, props);
    		ctxPropMap = new HashMap<String,String>(16);
    		for (Object key : props.keySet()){
    			String keyStr = key.toString();
    			String value = String.valueOf(props.get(keyStr));
    			ctxPropMap.put(keyStr,value);
    		}
    	}
    
    	/**
    	 *获取注解
    	 *@param name
    	 *@return
    	 */
    	public static String getCtxProp(String name) {
    		return ctxPropMap.get(name);
    	}
    }

所以需要将本地配置和apollo配置整合起来.

参考apollo github wiki - Java客户端使用指南3.2 Spring整合方式:

[https://github.com/ctripcorp/apollo/wiki/Java%E5%AE%A2%E6%88%B7%E7%AB%AF%E4%BD%BF%E7%94%A8%E6%8C%87%E5%8D%97\#3213-spring-boot%E9%9B%86%E6%88%90%E6%96%B9%E5%BC%8F%E6%8E%A8%E8%8D%90][https_github.com_ctripcorp_apollo_wiki_Java_E5_AE_A2_E6_88_B7_E7_AB_AF_E4_BD_BF_E7_94_A8_E6_8C_87_E5_8D_97_3213-spring-boot_E9_9B_86_E6_88_90_E6_96_B9_E5_BC_8F_E6_8E_A8_E8_8D_90]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3NzcyNTE4_size_16_color_FFFFFF_t_70][]

人家官方已经不推荐使用PropertyPlaceholderConfigurer, 推荐用PropertySourcesPlaceholderConfigurer.

难点是, 如何将apollo中的配置读取出来, 和本地配置整合在一起.

但是我知道, apollo的配置会加载到environment中, 于是我便注入environment.

@Autowired
    ConfigurableEnvironment environment;

注入的environment为空怎么办?

在改造过程中了解过SpringBoot如何实现自动配置, 看源码的时候学到一招, 就是使用回调.

@Override
    public void setEnvironment(Environment environment) {
       this.environment = environment;
    }

这样一来, 我解决了注入Environment为空的问题.

再一个难点就是, 如何从Environment中读取到apollo中的配置.

参考apollo的源码, 我了解到apollo配置加载到环境中最重要的一部分, 下面是apollo的源码可以参考一下:

package com.ctrip.framework.apollo.spring.boot;
    
    import com.ctrip.framework.apollo.Config;
    import com.ctrip.framework.apollo.ConfigService;
    import com.ctrip.framework.apollo.core.ConfigConsts;
    import com.ctrip.framework.apollo.spring.config.ConfigPropertySourceFactory;
    import com.ctrip.framework.apollo.spring.config.PropertySourcesConstants;
    import com.ctrip.framework.apollo.spring.util.SpringInjector;
    import com.google.common.base.Splitter;
    import com.google.common.base.Strings;
    import java.util.List;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.context.ApplicationContextInitializer;
    import org.springframework.context.ConfigurableApplicationContext;
    import org.springframework.core.env.CompositePropertySource;
    import org.springframework.core.env.ConfigurableEnvironment;
    
    /**
     * Initialize apollo system properties and inject the Apollo config in Spring Boot bootstrap phase
     *
     * <p>Configuration example:</p>
     * <pre class="code">
     *   # set app.id
     *   app.id = 100004458
     *   # enable apollo bootstrap config and inject 'application' namespace in bootstrap phase
     *   apollo.bootstrap.enabled = true
     * </pre>
     *
     * or
     *
     * <pre class="code">
     *   # set app.id
     *   app.id = 100004458
     *   # enable apollo bootstrap config
     *   apollo.bootstrap.enabled = true
     *   # will inject 'application' and 'FX.apollo' namespaces in bootstrap phase
     *   apollo.bootstrap.namespaces = application,FX.apollo
     * </pre>
     */
    public class ApolloApplicationContextInitializer implements
        ApplicationContextInitializer<ConfigurableApplicationContext> {
      private static final Logger logger = LoggerFactory.getLogger(ApolloApplicationContextInitializer.class);
      private static final Splitter NAMESPACE_SPLITTER = Splitter.on(",").omitEmptyStrings().trimResults();
      private static final String[] APOLLO_SYSTEM_PROPERTIES = {"app.id", ConfigConsts.APOLLO_CLUSTER_KEY,
          "apollo.cacheDir", ConfigConsts.APOLLO_META_KEY};
    
      private final ConfigPropertySourceFactory configPropertySourceFactory = SpringInjector
          .getInstance(ConfigPropertySourceFactory.class);
    
      @Override
      public void initialize(ConfigurableApplicationContext context) {
        ConfigurableEnvironment environment = context.getEnvironment();
    
        initializeSystemProperty(environment);
    
        String enabled = environment.getProperty(PropertySourcesConstants.APOLLO_BOOTSTRAP_ENABLED, "false");
        if (!Boolean.valueOf(enabled)) {
          logger.debug("Apollo bootstrap config is not enabled for context {}, see property: ${
       {}}", context, PropertySourcesConstants.APOLLO_BOOTSTRAP_ENABLED);
          return;
        }
        logger.debug("Apollo bootstrap config is enabled for context {}", context);
    
        if (environment.getPropertySources().contains(PropertySourcesConstants.APOLLO_BOOTSTRAP_PROPERTY_SOURCE_NAME)) {
          //already initialized
          return;
        }
    
        String namespaces = environment.getProperty(PropertySourcesConstants.APOLLO_BOOTSTRAP_NAMESPACES, ConfigConsts.NAMESPACE_APPLICATION);
        logger.debug("Apollo bootstrap namespaces: {}", namespaces);
        List<String> namespaceList = NAMESPACE_SPLITTER.splitToList(namespaces);
    
        CompositePropertySource composite = new CompositePropertySource(PropertySourcesConstants.APOLLO_BOOTSTRAP_PROPERTY_SOURCE_NAME);
        for (String namespace : namespaceList) {
          Config config = ConfigService.getConfig(namespace);
    
          composite.addPropertySource(configPropertySourceFactory.getConfigPropertySource(namespace, config));
        }
    
        environment.getPropertySources().addFirst(composite);
      }
    
      /**
       * To fill system properties from environment config
       */
      void initializeSystemProperty(ConfigurableEnvironment environment) {
        for (String propertyName : APOLLO_SYSTEM_PROPERTIES) {
          fillSystemPropertyFromEnvironment(environment, propertyName);
        }
      }
    
      private void fillSystemPropertyFromEnvironment(ConfigurableEnvironment environment, String propertyName) {
        if (System.getProperty(propertyName) != null) {
          return;
        }
    
        String propertyValue = environment.getProperty(propertyName);
    
        if (Strings.isNullOrEmpty(propertyValue)) {
          return;
        }
    
        System.setProperty(propertyName, propertyValue);
      }
    }

看到这一步![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3NzcyNTE4_size_16_color_FFFFFF_t_70 1][] ![20190912103453850.png][]

我好像明白了很多.

所以我的PropertyConfigurer最终为:

/**
     * 获取到当前架包中资源文件夹下的Properties配置文件
     */
    public class PropertyConfigurer extends PropertySourcesPlaceholderConfigurer {
    
    	private static Map<String,String> ctxPropMap;
    	private static final Logger LOGGER = LoggerFactory.getLogger(PropertyConfigurer.class);
    	@Autowired
    	ConfigurableEnvironment environment;
    
    	@Override
    	public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
            try {
                Properties properties = super.mergeProperties();
                ctxPropMap = new HashMap<String,String>(16);
    			CompositePropertySource propertySource = (CompositePropertySource) environment.getPropertySources().get("ApolloBootstrapPropertySources");
    			if (propertySource != null){
    				// Apollo管理的配置放入ctxPropMap
    				for (String name : propertySource.getPropertyNames()){
    					ctxPropMap.put(name, environment.getProperty(name));
    				}
    			}
    			// 本地管理的配置放入ctxPropMap
    			for (Object key : properties.keySet()){
                    String keyStr = key.toString();
                    String value = String.valueOf(properties.get(keyStr));
                    ctxPropMap.put(keyStr,value);
                }
            } catch (IOException e) {
                e.printStackTrace();
    			LOGGER.error("Error occurred when return a merged Properties instance containing both the loaded properties and properties set on this FactoryBean.");
            }
    	}
    
    	/**
    	 * 获取注解
    	 * @param name
    	 * @return
    	 */
    	public static String getCtxProp(String name) {
    		return ctxPropMap.get(name);
    	}
    
    	/**
    	 * 获取HashMap键值对
    	 * @return
    	 */
    	public static Map<String, String> getCtxPropMap() {
    		return ctxPropMap;
    	}
    
    	@Override
    	public void setEnvironment(Environment environment) {
    		this.environment = (ConfigurableEnvironment) environment;
    	}
    
    }

最重要的一行代码:

CompositePropertySource propertySource = (CompositePropertySource) environment.getPropertySources().get("ApolloBootstrapPropertySources");

**职场小白, 如有错误, 还望及时批评指正, 感谢!!! **

[https_github.com_ctripcorp_apollo_wiki_Java_E5_AE_A2_E6_88_B7_E7_AB_AF_E4_BD_BF_E7_94_A8_E6_8C_87_E5_8D_97_3213-spring-boot_E9_9B_86_E6_88_90_E6_96_B9_E5_BC_8F_E6_8E_A8_E8_8D_90]: https://github.com/ctripcorp/apollo/wiki/Java%E5%AE%A2%E6%88%B7%E7%AB%AF%E4%BD%BF%E7%94%A8%E6%8C%87%E5%8D%97#3213-spring-boot%E9%9B%86%E6%88%90%E6%96%B9%E5%BC%8F%E6%8E%A8%E8%8D%90
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3NzcyNTE4_size_16_color_FFFFFF_t_70]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/de0d378e07a14f03b0320e0ca5238f43.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3NzcyNTE4_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20190912103419806.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzM3NzcyNTE4,size_16,color_FFFFFF,t_70
[20190912103453850.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/bade867a424349958089406f71ef589a.png