集成RocketMQ，项目启动后rocketmq_client.log日志文件配置

项目添加RocketMQ以后启动项目时会在user.home下创建一个rocketmq_client.log日志文件，文件全路径是：${user.home}/logs/rocketmqlogs/rocketmq_client.log。由于我们的服务器数据盘不在home路径下,会导致系统盘空间占用不断增大，所以需要配置日志目录到其他路径。

通过源码org.apache.rocketmq.client.log.ClientLogger可以看到，在项目启动时会读取是否启动slf4j配置，读取的配置名称是：rocketmq.client.logUseSlf4j，如果是则会直接获取logger名称为RocketmqClient,Appender名称为RocketmqClientAppender的配置，以下是源码：

public class ClientLogger {

    public static final String CLIENT_LOG_USESLF4J = "rocketmq.client.logUseSlf4j";
    public static final String CLIENT_LOG_ROOT = "rocketmq.client.logRoot";
    public static final String CLIENT_LOG_MAXINDEX = "rocketmq.client.logFileMaxIndex";
    public static final String CLIENT_LOG_FILESIZE = "rocketmq.client.logFileMaxSize";
    public static final String CLIENT_LOG_LEVEL = "rocketmq.client.logLevel";
    public static final String CLIENT_LOG_ADDITIVE = "rocketmq.client.log.additive";
    public static final String CLIENT_LOG_FILENAME = "rocketmq.client.logFileName";
    public static final String CLIENT_LOG_ASYNC_QUEUESIZE = "rocketmq.client.logAsyncQueueSize";
    public static final String ROCKETMQ_CLIENT_APPENDER_NAME = "RocketmqClientAppender";

    private static final InternalLogger CLIENT_LOGGER;

    private static final boolean CLIENT_USE_SLF4J;

    //private static Appender rocketmqClientAppender = null;

    static {
        // 获取是否启动slf4j配置
        CLIENT_USE_SLF4J = Boolean.parseBoolean(System.getProperty(CLIENT_LOG_USESLF4J, "false"));
        if (!CLIENT_USE_SLF4J) {
            InternalLoggerFactory.setCurrentLoggerType(InnerLoggerFactory.LOGGER_INNER);
            CLIENT_LOGGER = createLogger(LoggerName.CLIENT_LOGGER_NAME);
            createLogger(LoggerName.COMMON_LOGGER_NAME);
            createLogger(RemotingHelper.ROCKETMQ_REMOTING);
        } else {
            // 获取logger
            CLIENT_LOGGER = InternalLoggerFactory.getLogger(LoggerName.CLIENT_LOGGER_NAME);
        }
    }

    // .........
}

网上很多文章都说可以通过在配置文件中添加rocketmq.client.logUseSlf4j即可，但是我添加后通过debug上面的static块发现并没有读取到，所以只能在项目启动类中添加以下代码：

public class Application {
    public static void main(String[] args) {
        System.setProperty(ClientLogger.CLIENT_LOG_USESLF4J,"true");
        SpringApplication.run(Application.class, args);
    }
}

添加完以上代码后，然后在配置日志的输出，我用的logback作为日志输出，具体配置如下：

<!-- rocketmq日志 -->
    <appender name="RocketmqClientAppender" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_DIR}/${APP_NAME}/rocketmq_client.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
            <fileNamePattern>${LOG_DIR}/${APP_NAME}/history/rocketmq_client.%d{yyyyMMdd}.%i.log</fileNamePattern>
            <maxFileSize>${LOG_MAXFILESIZE}</maxFileSize>
            <!--保留时间,单位:天-->
            <maxHistory>${LOG_FILEMAXDAY}</maxHistory>
        </rollingPolicy>
        <encoder charset="UTF-8">
            <pattern>%d{yy-MM-dd.HH:mm:ss.SSS} [%-16t] %-5p %-22c{0} %X{ServiceId} - %m%n</pattern>
        </encoder>
    </appender>
    <logger name="RocketmqClient" additivity="false">
        <level value="warn" />
        <appender-ref ref="RocketmqClientAppender"/>
    </logger>

上面的变量可以直接固定，我的项目中所有服务模块中使用了一个统一的日志文件，所以需要在日志配置的xml顶部配置属性，如果使用的是logback.xml则把下面的springProperty标签换成property标签，我使用的是logback-spring.xml，所以使用的springProperty标签：

<configuration>
    <contextName>${APP_NAME}</contextName>
    <springProperty name="APP_NAME" scope="context" source="spring.application.name"/>
    <springProperty name="LOG_DIR" scope="context" source="platform.logging.dir" defaultValue="../logs/${APP_NAME}"/>
    <springProperty name="LOG_LEVEL" scope="context" source="platform.logging.level" defaultValue="INFO"/>
    <springProperty name="LOG_POINT_FILE" scope="context" source="platform.logging.dir" defaultValue="../logs/point"/>
    <springProperty name="LOG_MAXFILESIZE" scope="context" source="platform.logging.maxsize" defaultValue="200MB"/>
    <springProperty name="LOG_FILEMAXDAY" scope="context" source="platform.logging.maxday" defaultValue="60"/>
    <springProperty name="ServerIP" scope="context" source="spring.cloud.client.ip-address" defaultValue="0.0.0.0"/>
    <springProperty name="ServerPort" scope="context" source="server.port" defaultValue="0000"/>
</configuration>

配置完毕，启动项目可以看到日志文件已经到指定的位置了