基于logback的系统日志配置及FAQ

何时

一个走在不那么迷茫路上的publisher_

系统日志配置相关

现在java体系的工程，框架工程基本上是面向slf4j使用日志系统，实现层主要由logback和log4j，我们采用的是logback，现在主要说明下logback工程的使用。

自定义日志存放路径

如果需要自定义日志存放路径，修改logPath的属性即可，比如在配置中心或者bootstrap.properties文件里面配置下logPath=d:\logs

自定义日志结转路径

<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
    <!-- daily rollover -->
    <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/i18nMS-%d{yyyy-MM-dd}.log.gz</fileNamePattern>
    <!-- keep 7 days' worth of history -->
    <maxHistory>7</maxHistory>
</rollingPolicy>

如上面示例所示，通过配置fileNamePattern实现自定义结转日志路径，最后结转的效果类似于d:\logs\2021-01-12\i18nMS-2021-01-12.log.gz，此日志也已经实现了日志的压缩。

注意事项：使用日志结转时，rollingPolicy需要使用ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy或者ch.qos.logback.core.rolling.TimeBasedRollingPolicy。

自定义日志保留时间

<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
    <!-- daily rollover -->
    <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/Swagger-%d{yyyy-MM-dd}.log.gz</fileNamePattern>
    <!-- keep 7 days' worth of history -->
    <maxHistory>7</maxHistory>
</rollingPolicy>

如上面所示，可以在rollingPolicy里面通过配置maxHistory配置日志最大保留时间策略，如果不配置，默认永久保留。

注意事项：使用日志结转时，rollingPolicy需要使用ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy或者ch.qos.logback.core.rolling.TimeBasedRollingPolicy。

自定义日志按照日志文件大小结转

<rollingPolicy
    class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
    <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/${SERVICE_CODE}.%d{yyyy-MM-dd}.%i.log.gz</fileNamePattern>
    <maxFileSize>200MB</maxFileSize>
</rollingPolicy>

如上面所示，可以通过将rollingPolicy使用ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy，通过配置fileNamePattern，配置好 “%i”，然后配置好结转大小。上面的例子里面是按照日志文件200MB大小进行的结转。最后结转的效果类似于d:\logs\2021-01-12\i18nMS-2021-01-12.0.log.gz。

动态配置日志是否启用

之前有个业务场景，需要抓取服务启动过程中的日志，主要是为了抓取错误日志，方便服务启动失败之后，快速定位问题。我们进行了如下配置：

<!--服务启动日志-->
    <appender name="EC_GENERATOR_SERVICE_LOG_FILE" class="ch.qos.logback.classic.sift.SiftingAppender">
        <discriminator>
            <Key>serviceLogName</Key>
            <DefaultValue>serviceLogName</DefaultValue>
        </discriminator>
            <appender name="EC_SERVCIE_LOG_FILE" class="ch.qos.logback.core.FileAppender">
                <file>${LOG_PATH}/publish/${serviceLogName}.log</file>
                <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
                    <Pattern>[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level %logger{80} [%X{EC.Entity}] - %msg %ex%n</Pattern>
                </encoder>
            </appender>
        </sift>
    </appender>
    <root level="INFO">
        <appender-ref ref="EC_GENERATOR_SERVICE_LOG_FILE" />
    </root>

启动类里面加入了如下配置：

String taskId = System.getProperty("task.id");
MDC.put("serviceLogName", taskId+"-${bootName}");
SpringApplication.run(${bootName}.class, args);
LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
loggerContext.getLogger("root").detachAppender("EC_GENERATOR_SERVICE_LOG_FILE");

首先在启动前，生成一个taskid，通过serviceLogName传入到日志系统中，发布结束后，通过loggerContext移除EC_GENERATOR_SERVICE_LOG_FILE，即可实现appender的移除。既然可以移除appender，也就可以实现动态新增、修改appender。

动态修改日志级别

上面这种场景，可以处理的东西比较多，当然也可以修改日志级别，然是上面这种方式侵入业务实现，下面再讲两种不侵入业务实现而动态修改日志级别的方式。

方案一：通过再配置中心或者配置文件中入如下配置logging.level.org.hibernate.SQL=WARN，我们就动态修改了org.hibernate.SQL的日志级别
方案二：工程结构里面依赖spring-boot-starter-actuator，同时需要开启端点配置，我们自己的工程默认都开启了。通过postman，使用post方式访问http://[ip]:[port]/actuator/loggers/root，并传入如下参数
{
"org.hibernate.SQL":"WARN"
}

基础logback.xml模板

最后放一个完整的logback模板，这个算配置的比较全了。

<#noparse><?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <!--定义日志保存的路径 -->
    <springProperty scope="context" name="LOG_PATH" source="logPath" />
    <conversionRule conversionWord="clr"
                    converterClass="org.springframework.boot.logging.logback.ColorConverter"/>
    <conversionRule conversionWord="wex"
                    converterClass="org.springframework.boot.logging.logback.WhitespaceThrowableProxyConverter"/>
    <conversionRule conversionWord="wEx"
                    converterClass="org.springframework.boot.logging.logback.ExtendedWhitespaceThrowableProxyConverter"/>
    <springProperty scope="context" name="SERVER_PORT" source="server.port"/>
    <springProperty scope="context" name="SERVER_ADDRESS" source="server.address"/>
    <springProperty scope="context" name="SERVICE_CODE" source="serviceCode"/>
    <property name="CONSOLE_LOG_PATTERN"
        value="${CONSOLE_LOG_PATTERN:-%clr(%d{HH:mm:ss.SSS}){faint} %clr(${LOG_LEVEL_PATTERN:-%5p}) %clr(${PID:- }){magenta} %clr(---){faint} %clr([%15.15t]){faint} %clr(%-40.40logger{39}){cyan} %clr(:){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}}" />
    <property name="FILE_LOG_PATTERN"
        value="${FILE_LOG_PATTERN:-%d{yyyy-MM-dd HH:mm:ss.SSS} ${LOG_LEVEL_PATTERN:-%5p} ${SERVER_ADDRESS}:${SERVER_PORT} ${PID:- } --- [%t] %-40.40logger{39} : %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}}" />
    <!--输出到控制台 -->
    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>INFO</level>
        </filter>
        <encoder>
            <pattern>${CONSOLE_LOG_PATTERN}</pattern>
        </encoder>
    </appender>
    <!--输出到文件 -->
    <appender name="allFile" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_PATH}/${SERVICE_CODE}.log</file>
        <filter class="com.demo.orchid.ec.cache.EcCacheLogFilter"/>
        <rollingPolicy
            class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
            <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/${SERVICE_CODE}.%d{yyyy-MM-dd}.%i.log.gz</fileNamePattern>
            <maxFileSize>200MB</maxFileSize>
        </rollingPolicy>
        <encoder>
            <pattern>${FILE_LOG_PATTERN}</pattern>
            <charset class="java.nio.charset.Charset">UTF-8</charset>
        </encoder>
    </appender>
    <!--输出到error文件 -->
    <appender name="errorFile" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_PATH}/${SERVICE_CODE}-error.log</file>
        <rollingPolicy
            class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/${SERVICE_CODE}-error.%d{yyyy-MM-dd}.log.gz</fileNamePattern>
        </rollingPolicy>
        <encoder>
            <pattern>${FILE_LOG_PATTERN}</pattern>
        </encoder>
        <append>true</append>
        <!-- 此日志文件只记录error级别的 -->
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>ERROR</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>DENY</onMismatch>
        </filter>
    </appender>
    <appender name="REDIS_LOG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_PATH}/redisMS.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
                <!-- daily rollover -->
                <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/redisMS-%d{yyyy-MM-dd}.log.gz</fileNamePattern>
                <!-- keep 7 days' worth of history -->
                <maxHistory>7</maxHistory>
        </rollingPolicy>
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <Pattern>[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level ${SERVER_ADDRESS}:${SERVER_PORT} %-28.28thread %-64.64logger{64} %X{medic.eventCode} %msg %ex%n</Pattern>
        </encoder>
    </appender>
    <appender name="I18N_LOG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_PATH}/i18nMS.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
                <!-- daily rollover -->
                <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/i18nMS-%d{yyyy-MM-dd}.log.gz</fileNamePattern>
                <!-- keep 7 days' worth of history -->
                <maxHistory>7</maxHistory>
        </rollingPolicy>
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <Pattern>[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level ${SERVER_ADDRESS}:${SERVER_PORT} %-28.28thread %-64.64logger{64} %X{medic.eventCode} %msg %ex%n</Pattern>
        </encoder>
    </appender>
    <appender name="KAFKA_LOG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_PATH}/KafkaMS.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
                <!-- daily rollover -->
                <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/KafkaMS-%d{yyyy-MM-dd}.log.gz</fileNamePattern>
                <!-- keep 7 days' worth of history -->
                <maxHistory>7</maxHistory>
        </rollingPolicy>
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <Pattern>[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level ${SERVER_ADDRESS}:${SERVER_PORT} %-28.28thread %-64.64logger{64} %X{medic.eventCode} %msg %ex%n</Pattern>
        </encoder>
    </appender>
    <appender name="SWAGGER_LOG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_PATH}/Swagger.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
                <!-- daily rollover -->
                <fileNamePattern>${LOG_PATH}/%d{yyyy-MM-dd}/Swagger-%d{yyyy-MM-dd}.log.gz</fileNamePattern>
                <!-- keep 7 days' worth of history -->
                <maxHistory>7</maxHistory>
        </rollingPolicy>
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <Pattern>[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level ${SERVER_ADDRESS}:${SERVER_PORT} %-28.28thread %-64.64logger{64} %X{medic.eventCode} %msg %ex%n</Pattern>
        </encoder>
    </appender>
    <!--服务启动日志-->
    <appender name="EC_GENERATOR_SERVICE_LOG_FILE" class="ch.qos.logback.classic.sift.SiftingAppender">
        <discriminator>
            <Key>serviceLogName</Key>
            <DefaultValue>serviceLogName</DefaultValue>
        </discriminator>
            <appender name="EC_SERVCIE_LOG_FILE" class="ch.qos.logback.core.FileAppender">
                <file>${LOG_PATH}/publish/${serviceLogName}.log</file>
                <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
                    <Pattern>[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level %logger{80} [%X{EC.Entity}] - %msg %ex%n</Pattern>
                </encoder>
            </appender>
        </sift>
    </appender>
    <logger level="INFO" additivity="false" name="org.redisson">
        <appender-ref ref="REDIS_LOG_FILE" />
    </logger>
    <logger level="INFO" additivity="false" name="com.demo.demo2.framework.cloud.i18n.resource.utils.MessageResourceWrapper">
        <appender-ref ref="I18N_LOG_FILE" />
    </logger>
    <logger level="OFF" additivity="false" name="org.hibernate.orm.deprecation" >
        <appender-ref ref="allFile" />
    </logger>
    <!-- hibernate sql日志 -->
    <logger level="DEBUG" additivity="false" name="org.hibernate.SQL">
        <appender-ref ref="allFile" />
    </logger>
    <logger level="TRACE" additivity="false" name="org.hibernate.type.descriptor.sql.BasicBinder">
        <appender-ref ref="allFile" />
    </logger>
    <logger level="DEBUG" additivity="false" name="com.demo.license">
        <appender-ref ref="KAFKA_LOG_FILE" />
    </logger>
    <logger level="ERROR" additivity="false" name="org.apache.kafka">
        <appender-ref ref="KAFKA_LOG_FILE" />
    </logger>
    <logger level="ERROR" additivity="false" name="org.springframework.kafka">
        <appender-ref ref="KAFKA_LOG_FILE" />
    </logger>
    <logger level="WARN" additivity="false" name="org.springframework.context.support">
        <appender-ref ref="KAFKA_LOG_FILE" />
    </logger>
    <logger level="ERROR" additivity="false" name="springfox.documentation.spring.web">
        <appender-ref ref="SWAGGER_LOG_FILE" />
    </logger>
    <logger level="OFF" additivity="false" name="com.alibaba.nacos.client.config.impl.ClientWorker">
        <appender-ref ref="allFile" />
    </logger>
    <logger level="ERROR" additivity="false" name="com.alibaba.nacos.client.naming">
        <appender-ref ref="allFile" />
    </logger>
    <!-- 生产环境，将此级别配置为适合的级别，以防日志文件太多或影响程序性能 -->
    <root level="INFO">
        <appender-ref ref="errorFile" />
        <appender-ref ref="allFile" />
        <appender-ref ref="console" />