如何配置Logback：一份简单易懂的指南

<?xml version="1.0" encoding="UTF-8"?>
<configuration scan="true">

    <!-- 日志级别 -->
    <property name="log.root.level" value="INFO"/>
    <!-- 其他日志级别 -->
    <property name="log.other.level" value="DEBUG"/>
    <!-- 模块名称， 影响日志配置名，日志文件名 -->
    <property name="log.moduleName" value="game"/>
    <!--日志文件的保存路径,首先查找系统属性-Dlog.dir,如果存在就使用其；否则，在当前目录下创建名为logs目录做日志存放的目录 -->
    <property name="log.base" value="${log.dir:-logs}/${log.moduleName}"/>
    <property name="log.max.size" value="1MB"/> <!-- 日志文件大小,超过这个大小将被压缩 -->
    <!-- 彩色日志 -->
    <!-- 彩色日志依赖的渲染类 -->
    <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"/>

    <!-- 彩色日志格式 -->
    <property name="CONSOLE_LOG_PATTERN"
              value="${CONSOLE_LOG_PATTERN:-%clr(%d{yyyy-MM-dd HH:mm:ss.SSS}){faint} %clr(${LOG_LEVEL_PATTERN:-%5p}) %clr(${PID:- }){magenta} %clr([%8.15t]){faint} %clr(%-40.40logger{39}){cyan} %clr(:){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}} "/>

    <property name="CONSOLE_LOG_PATTERN_X"
              value="%clr(%d{HH:mm:ss.SSS}){faint} %clr(${LOG_LEVEL_PATTERN:-%5p}) %clr(${PID:- }){magenta} %clr([%8.15t]){faint} %yellow(at %class.%method) \\(%file:%line\\) %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}"/>

    <property name="CONSOLE_LOG_PATTERN_XX"
              value="%clr(%d{HH:mm:ss.SSS}){faint} %clr(${LOG_LEVEL_PATTERN:-%5p}) %clr([%8.15t]){faint} %yellow(at %class.%method) \\(%file:%line\\) %clr(:){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}"/>

    <!-- 时间, 日志级别, 线程名 %clr([%8.15t]) -->
    <property name="CONSOLE_LOG_PATTERN_XXX"
              value="%clr(%d{HH:mm:ss.SSS}){faint} %clr(${LOG_LEVEL_PATTERN:-%5p}) %clr([%8.15t]){faint} %cyan(%clr(%-40.40logger{50}.%method)){cyan}\\(%file:%line\\) %clr(:){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}"/>

    <!--控制台输出 -->
    <appender name="stdout" class="ch.qos.logback.core.ConsoleAppender">
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <!--格式化输出：%d表示日期，%thread表示线程名，%-5level：级别从左显示5个字符宽度%msg：日志消息，%n是换行符-->
            <!-- <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %highlight(%-5level) %cyan(%logger{50}) - %highlight(%msg) %n</pattern>-->
            <pattern>${CONSOLE_LOG_PATTERN_XXX}</pattern>
            <charset>utf8</charset>
        </encoder>
    </appender>

    <!-- 用来保存输出所有级别的日志 -->
    <appender name="file.all" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <!-- 设置日志不超过${log.max.size}时的保存路径，注意如果是web项目会保存到Tomcat的bin目录 下 -->
        <File>${log.base}/${log.moduleName}.log</File>
        <!-- 滚动记录文件，先将日志记录到指定文件，当符合某个条件时，将日志记录到其他文件。 -->
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <FileNamePattern>${log.base}/archive/${log.moduleName}_all_%d{yyyy-MM-dd}.%i.log.zip</FileNamePattern>
            <!-- 文件输出日志 (文件大小策略进行文件输出，超过指定大小对文件备份) -->
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>${log.max.size}</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
        </rollingPolicy>
        <!-- 日志输出的文件的格式 -->
        <layout class="ch.qos.logback.classic.PatternLayout">
            <pattern>%date{yyyy-MM-dd HH:mm:ss.SSS} %-5level[%thread]%logger{80}.%method:%L -%msg%n</pattern>
        </layout>
    </appender>

    <!-- 这也是用来保存输出所有级别的日志 -->
    <appender name="file.all.other" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <File>${log.base}/${log.moduleName}_other.log</File>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <FileNamePattern>${log.base}/archive/${log.moduleName}_other_%d{yyyy-MM-dd}.%i.log.zip
            </FileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>${log.max.size}</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
        </rollingPolicy>
        <layout class="ch.qos.logback.classic.PatternLayout">
            <pattern>%date{yyyy-MM-dd HH:mm:ss.SSS} %-5level [%thread] %logger{56}.%method:%L -%msg%n</pattern>
        </layout>
    </appender>

    <!-- 只用保存输出error级别的日志 -->
    <appender name="file.error" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <File>${log.base}/${log.moduleName}_err.log</File>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <FileNamePattern>
                ${log.base}/archive/${log.moduleName}_err_%d{yyyy-MM-dd}.%i.log.zip
            </FileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <!--达到上限压缩 单个文件大小限制-->
                <maxFileSize>${log.max.size}</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>

            <!--cleanHistoryOnStart：true登录清理默认false -->
            <cleanHistoryOnStart>true</cleanHistoryOnStart>
            <!--日志文件保留1天 注：maxHistory不为0 totalSizeCap才会生效-->
            <maxHistory>1</maxHistory>
            <!--日志文件大小（KB MB GB）-->
<!--            <totalSizeCap>50KB</totalSizeCap>-->

        </rollingPolicy>
        <layout class="ch.qos.logback.classic.PatternLayout">
            <pattern>%date{yyyy-MM-dd HH:mm:ss.SSS} %-5level [%thread] %logger{56}.%method:%L - %msg%n</pattern>
        </layout>
        <!-- 下面为配置只输出error级别的日志 -->
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>ERROR</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>DENY</onMismatch>
        </filter>
    </appender>

    <!-- 不丢失日志.默认的,如果队列的80%已满,则会丢弃TRACT、DEBUG、INFO级别的日志 -->
    <!-- 更改默认的队列的深度,该值会影响性能.默认值为256 -->
    <!-- 添加附加的appender,最多只能添加一个 -->
    <appender name="file.async" class="ch.qos.logback.classic.AsyncAppender">
        <discardingThreshold>0</discardingThreshold>
        <queueSize>256</queueSize>
        <includeCallerData>true</includeCallerData>
        <appender-ref ref="file.all"/>
    </appender>

    <!-- 使用异步来记录其他信息-->
    <appender name="file.async.other" class="ch.qos.logback.classic.AsyncAppender">
        <discardingThreshold>0</discardingThreshold>
        <queueSize>256</queueSize>
        <includeCallerData>true</includeCallerData>
        <appender-ref ref="file.all.other"/>
    </appender>

    <!-- 为某个包下的所有类的指定Appender 这里也可以指定类名称例如：com.aa.bb.ClassName -->
    <logger name="com.lin" additivity="false">
        <level value="${log.root.level}"/>
        <appender-ref ref="stdout"/>
        <appender-ref ref="file.async"/><!-- 即com.lin包下级别为 ${log.root.level}的才会使用file.async来打印 -->
        <appender-ref ref="file.error"/>
    </logger>

    <!-- root将级别为${log.root.level}及大于${log.root.level}的日志信息交给已经配置好的名为“Console”的appender处理，“Console”appender将信息打印到Console,其它同理 -->
    <root level="${log.root.level}">
        <appender-ref ref="stdout"/> <!--  标识这个appender将会添加到这个logger -->
<!--        <appender-ref ref="file.async.other"/>-->
        <appender-ref ref="file.error"/>
    </root>
</configuration>

     <!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.11</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
            <version>2.7.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot</artifactId>
            <version>2.7.0</version>
        </dependency>