Apollo(四)-Java环境调用参数-代码例子

骑猪看日落 2021-11-16 19:48 607阅读 0赞

### Apollo-Java环境调用参数-代码例子 ###

*  说明
 *  前提
 *  读参数
 *   *   *  代码
         *   *   *  pom.xml
                 *  SimpleApolloConfigDemo.java
                 *  app.properties
                 *  log4j2.xml
                 *  spring.xml
         *  运行
 *  参数修改时onChange事件

# 说明 #

下面以github下载的源码中SimpleApolloConfigDemo为例

# 前提 #

1.启动apollo的apollo-configservice、apollo-adminservice、apollo-portal服务（具体见[Apollo(二)][Apollo]），或者已部署到环境的则在环境启动相应的程序；

# 读参数 #

### 代码 ###

SimpleApolloConfigDemo.java、app.properties、application.yml、log4j2.xml、spring.xml拷贝到自己的工程，若包名改变，相应配置文件要改过来；具体工程目录和代码如下所示：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NuZGF5WVU_size_16_color_FFFFFF_t_70]

##### pom.xml #####

<properties>
            <spring.version>5.1.7.RELEASE</spring.version>
            <spring-boot.version>2.0.5.RELEASE</spring-boot.version>
            <spring-cloud.version>Finchley.SR1</spring-cloud.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>com.ctrip.framework.apollo</groupId>
                <artifactId>apollo-client</artifactId>
                
                <version>1.4.0</version>
            </dependency>
            
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-context</artifactId>
                <version>${spring.version}</version>
            </dependency>
            
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
                <version>${spring-boot.version}</version>
                <exclusions>
                    <exclusion>
                        <groupId>org.springframework.boot</groupId>
                        <artifactId>spring-boot-starter-logging</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-log4j2</artifactId>
                <version>${spring-boot.version}</version>
            </dependency>
            
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-context</artifactId>
                <version>2.1.0.RELEASE</version>
            </dependency>
            <dependency>
                <groupId>org.apache.logging.log4j</groupId>
                <artifactId>log4j-core</artifactId>
                <version>2.11.0</version>
            </dependency>
            <dependency>
                <groupId>org.apache.logging.log4j</groupId>
                <artifactId>log4j-api</artifactId>
                <version>2.11.0</version>
            </dependency>
            <dependency>
                <groupId>org.apache.logging.log4j</groupId>
                <artifactId>log4j-slf4j-impl</artifactId>
                <version>2.11.0</version>
            </dependency>
            
            <dependency>
                <groupId>org.slf4j</groupId>
                <artifactId>jcl-over-slf4j</artifactId>
                <version>1.7.25</version>
            </dependency>
        </dependencies>

##### SimpleApolloConfigDemo.java #####

package com.ydfind.apollo;
    
    import com.google.common.base.Charsets;
    
    import com.ctrip.framework.apollo.Config;
    import com.ctrip.framework.apollo.ConfigChangeListener;
    import com.ctrip.framework.apollo.ConfigService;
    import com.ctrip.framework.apollo.model.ConfigChange;
    import com.ctrip.framework.apollo.model.ConfigChangeEvent;
    
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    
    import java.io.BufferedReader;
    import java.io.IOException;
    import java.io.InputStreamReader;
    
    /**
     * @author Jason Song(song_s@ctrip.com)
     */
    public class SimpleApolloConfigDemo {
        private static final Logger logger = LoggerFactory.getLogger(SimpleApolloConfigDemo.class);
        private String DEFAULT_VALUE = "undefined";
        private Config config;
    
        public SimpleApolloConfigDemo() {
            ConfigChangeListener changeListener = new ConfigChangeListener() {
                @Override
                public void onChange(ConfigChangeEvent changeEvent) {
                    logger.info("Changes for namespace {}", changeEvent.getNamespace());
                    for (String key : changeEvent.changedKeys()) {
                        ConfigChange change = changeEvent.getChange(key);
                        logger.info("Change - key: {}, oldValue: {}, newValue: {}, changeType: {}",
                                change.getPropertyName(), change.getOldValue(), change.getNewValue(),
                                change.getChangeType());
                    }
                }
            };
            config = ConfigService.getAppConfig();
            config.addChangeListener(changeListener);
        }
    
        private String getConfig(String key) {
            String result = config.getProperty(key, DEFAULT_VALUE);
            logger.info(String.format("Loading key : %s with value: %s", key, result));
            return result;
        }
    
        public static void main(String[] args) throws IOException {
            SimpleApolloConfigDemo apolloConfigDemo = new SimpleApolloConfigDemo();
            System.out.println(
                    "Apollo Config Demo. Please input key to get the value. Input quit to exit.");
            while (true) {
                System.out.print("> ");
                String input = new BufferedReader(new InputStreamReader(System.in, Charsets.UTF_8)).readLine();
                if (input == null || input.length() == 0) {
                    continue;
                }
                input = input.trim();
                if (input.equalsIgnoreCase("quit")) {
                    System.exit(0);
                }
                apolloConfigDemo.getConfig(input);
            }
        }
    }

##### app.properties #####

apollo:
      bootstrap:
        enabled: true
        # will inject 'application' and 'TEST1.apollo' namespaces in bootstrap phase
        namespaces: application,TEST1.apollo,application.yaml

##### log4j2.xml #####

<?xml version="1.0" encoding="UTF-8"?>
    <configuration monitorInterval="60">
      <appenders>
        <Console name="Console" target="SYSTEM_OUT">
          <PatternLayout pattern="[apollo-demo][%t]%d %-5p [%c] %m%n"/>
        </Console>
        <Async name="Async" includeLocation="true">
          <AppenderRef ref="Console"/>
        </Async>
      </appenders>
      <loggers>
        <logger name="com.ydfind.apollo" additivity="false" level="DEBUG">
          <AppenderRef ref="Async"/>
        </logger>
        <root level="INFO">
          <AppenderRef ref="Async"/>
        </root>
      </loggers>
    </configuration>

##### spring.xml #####

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xmlns:context="http://www.springframework.org/schema/context"
           xmlns:apollo="http://www.ctrip.com/schema/apollo"
           xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
           http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
           http://www.ctrip.com/schema/apollo http://www.ctrip.com/schema/apollo.xsd">
        <apollo:config order="10"/>
        <apollo:config namespaces="TEST1.apollo,application.yaml" order="11"/>
    
        <bean class="com.ctrip.framework.apollo.demo.spring.xmlConfigDemo.bean.XmlBean">
            <property name="timeout" value="${timeout:200}"/>
            <property name="batch" value="${batch:100}"/>
        </bean>
    
        <context:annotation-config />
    </beans>

### 运行 ###

运行SimpleApolloConfigDemo.java的main函数，如下所示，能正确独处timeout的值为1000.  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NuZGF5WVU_size_16_color_FFFFFF_t_70 1]

# 参数修改时onChange事件 #

添加启动参数：-Denv=dev -Ddev\_meta=http://localhost:8080  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NuZGF5WVU_size_16_color_FFFFFF_t_70 2]  
重新编译后再运行程序，然后修改timeout的值，可以看到程序是可以拦截变化的  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NuZGF5WVU_size_16_color_FFFFFF_t_70 3]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NuZGF5WVU_size_16_color_FFFFFF_t_70 4]

[Apollo]: https://blog.csdn.net/sndayYU/article/details/97165983
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