SpringBoot 日志集成SLF4J —— 配置详解
1. maven依赖
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-loggingartifactId>
<version>2.6.13version>
dependency>
<dependency>
<groupId>org.slf4jgroupId>
<artifactId>slf4j-apiartifactId>
<version>1.7.32version>
dependency>
2. slf4j配置结构
configuration：配置根目录
conversionRule：彩色日志，配置之后控制台输出的日志信息是彩色的，非常好看
appender：日志输出配置规则
file：日志文件输出路径
encoder：日志文件输出格式
pattern：日志文件输出模板格式
charset：日志文件输出编码方式
rollingPolicy：日志记录器的滚动策略；简单来说就是一天过后把前一天的日志文件名变成 "2021-xx-xx.log"；每个日志文件最大尺寸多少，超过尺寸后多余部分生成一个新的日志文件等，一些动态的策略处理
fileNamePattern：滚动策略输出日志文件目录，及文件名模板；以尺寸策略来说，超过10m的文件，多余部分输出的文件名和路劲为appender的file值，已满10m的部分输出路径为此值
timeBasedFileNamingAndTriggeringPolicy：设置日志文件尺寸滚动策略
maxFilesSize：单个日志文件最大size
maxHistory：日志文件最大保存时间
filter：日志文件记录数据过滤器
level：只记录对应等级的记录
onMatch：常量：ACCEPT
onMismatch：常量：DENY
root：设置日志记录写入和控制器打印等级，低于这个等级的记录不写入日志文件，不在控制器打印
appender-ref：日志规则生效列表，值为appender对应的name属性，只有name存在appender-ref的appender配置才会生效；
logger：指定某个报下的日志输出规则，配置之后只要是这个包下产生的记录，都是遵循此规则，并且与root中配置的appender-ref重复的话，会叠加生效
appender-ref：使用的日志生成规则
springProfile：设置不同环境的配置，上诉标签除了configuration都可以放置在此标签内；会根据不同的环境，使用不同的规则
3. 案例详解
3.1 configuration
配置文件的根节点
<configuration scan="true" scanPeriod="10 seconds" debug="false">
<conversionRule ....>conversionRule>
<root ....>root>
<appender ...>appender>
configuration>
3.2 conversionRule
配置完彩色日志后，就可以在模板内使用彩色变量，使得输出的日志记录变成彩色的，稍后在pattern中举例使用彩色变量，现在先配置
<configuration scan="true" scanPeriod="10 seconds" debug="false"> ......一些其他的配置
<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"/>
configuration>
3.3 appender
日志输出规则
<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
<filter class="ch.qos.logback.classic.filter.ThresholdFilter">
<level>infolevel>
filter>
<encoder>
<Pattern>
${
CONSOLE_LOG_PATTERN:- //常量
%clr(%d{yyyy-MM-dd HH:mm:ss.SSS}){faint} //%clr表示使用conversionRule中conversionWord为clr的converterClass输出()中的变量文本;%d表示日期;{faint}表示颜色；颜色值有[faint:灰白,red,green,yellow,blue,magenta,cyan]
%clr(${LOG_LEVEL_PATTERN:-%5p})
%clr(${PID:- }){magenta}
%clr(---){faint}
%clr([%15.15t]){faint}
%clr(%-40.40logger{39}){cyan}
%clr(:){cyan}
%m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}
}
Pattern>
<charset>UTF-8charset>
encoder>
appender>
3.4 Pattern中特殊符号含义
-X号: X信息输出时左对齐；
%p: //输出日志信息优先级，即DEBUG，INFO，WARN，ERROR，FATAL,
%d: //输出日志时间点的日期或时间，默认格式为ISO8601，也可以在其后指定格式，比如：%d{yyy MMM dd HH:mm:ss,SSS}，输出类似：2002年10月18日 22：10：28，921
%r: //输出自应用启动到输出该log信息耗费的毫秒数
%c: //输出日志信息所属的类目，通常就是所在类的全名
%t: //输出产生该日志事件的线程名
%l: //输出日志事件的发生位置，相当于%C.%M(%F:%L)的组合,包括类目名、发生的线程，以及在代码中的行数。举例：Testlog4.main (TestLog4.java:10)
%x: //输出和当前线程相关联的NDC(嵌套诊断环境),尤其用到像java servlets这样的多客户多线程的应用中。
%%: //输出一个”%”字符
%F: //输出日志消息产生时所在的文件名称
%L: //输出代码中的行号
%m://输出代码中指定的消息,产生的日志具体信息
%n: //输出一个回车换行符，Windows平台为”\r\n”，Unix平台为”\n”输出日志信息换行
3.5 appender
根据等级设置多个日志输出规则，把不同等级的日志分别存储，配置多个appender
<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(${PID:- }){magenta} %clr(---){faint} %clr([%15.15t]){faint} %clr(%-40.40logger{39}){cyan} %clr(:){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}}"/>
<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
<filter class="ch.qos.logback.classic.filter.ThresholdFilter">
<level>infolevel>
filter>
<encoder>
<Pattern>${CONSOLE_LOG_PATTERN}Pattern>
<charset>UTF-8charset>
encoder>
appender>
<appender name="DEBUG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${log.path}/log_debug.logfile>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
<charset>UTF-8charset>
encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log.path}/debug/log-debug-%d{yyyy-MM-dd}.%i.logfileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MBmaxFileSize>
timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>15maxHistory>
rollingPolicy>
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>debuglevel>
<onMatch>ACCEPTonMatch>
<onMismatch>DENYonMismatch>
filter>
appender>
<appender name="INFO_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${log.path}/log_info.logfile>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
<charset>UTF-8charset>
encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log.path}/info/log-info-%d{yyyy-MM-dd}.%i.logfileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MBmaxFileSize>
timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>15maxHistory>
rollingPolicy>
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>infolevel>
<onMatch>ACCEPTonMatch>
<onMismatch>DENYonMismatch>
filter>
appender>
<appender name="WARN_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${log.path}/log_warn.logfile>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
<charset>UTF-8charset>
encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log.path}/warn/log-warn-%d{yyyy-MM-dd}.%i.logfileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>1KBmaxFileSize>
timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>15maxHistory>
rollingPolicy>
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>warnlevel>
<onMatch>ACCEPTonMatch>
<onMismatch>DENYonMismatch>
filter>
appender>
<appender name="ERROR_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${log.path}/log_error.logfile>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
<charset>UTF-8charset>
encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log.path}/error/log-error-%d{yyyy-MM-dd}.%i.logfileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MBmaxFileSize>
timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>15maxHistory>
rollingPolicy>
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>ERRORlevel>
<onMatch>ACCEPTonMatch>
<onMismatch>DENYonMismatch>
filter>
appender>
3.6 root
appender必须要放置在root中，才能生效
<root level="info">
<appender-ref ref="CONSOLE"/>
<appender-ref ref="DEBUG_FILE"/>
<appender-ref ref="INFO_FILE"/>
<appender-ref ref="WARN_FILE"/>
<appender-ref ref="ERROR_FILE"/>
root>
3.7 logger
更精确的指定annender生效范围
<logger name="com.example.mybitesstudy02.service" level="info">
<appender-ref ref="CONSOLE"/>
logger>
3.8 springProfile
指定不同环境下的日志配置，注意springProfile判断当前是处于什么环境，取决于spring boot配置文件(application.properties)的spring.profiles.active值，默认是default
<root level="info">
<appender-ref ref="DEBUG_FILE"/>
<appender-ref ref="INFO_FILE"/>
<appender-ref ref="WARN_FILE"/>
<appender-ref ref="ERROR_FILE"/>
root>
<springProfile name="dev">
<root level="info">
<appender-ref ref="CONSOLE"/>
root>
springProfile>
<springProfile name="pro">
<root level="info">
<appender-ref ref="CONSOLE"/>
<appender-ref ref="INFO_FILE"/>
<appender-ref ref="ERROR_FILE"/>
root>
springProfile>
4. 超详细配置案例
<configuration scan="true" scanPeriod="10 seconds">
<contextName>logbackcontextName>
<springProperty scope="context" name="log.path" source="logging.file.path"/>
<springProperty scope="context" name="log.name" source="logging.file.name"/>
<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" />
<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(---){faint} %clr([%15.15t]){faint} %clr(%-40.40logger{39}){cyan} %clr(:){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}}"/>
<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
<filter class="ch.qos.logback.classic.filter.ThresholdFilter">
<level>debuglevel>
filter>
<encoder>
<Pattern>${CONSOLE_LOG_PATTERN}Pattern>
<charset>UTF-8charset>
encoder>
appender>
<appender name="DEBUG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${log.path}/${log.name}_debug.logfile>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
<charset>UTF-8charset>
encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log.path}/${log.name}-debug-%d{yyyy-MM-dd}.%i.logfileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MBmaxFileSize>
timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>30maxHistory>
rollingPolicy>
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>debuglevel>
<onMatch>ACCEPTonMatch>
<onMismatch>DENYonMismatch>
filter>
appender>
<appender name="INFO_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${log.path}/${log.name}_info.logfile>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
<charset>UTF-8charset>
encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log.path}/${log.name}-info-%d{yyyy-MM-dd}.%i.logfileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MBmaxFileSize>
timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>30maxHistory>
rollingPolicy>
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>infolevel>
<onMatch>ACCEPTonMatch>
<onMismatch>DENYonMismatch>
filter>
appender>
<appender name="WARN_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${log.path}/${log.name}_warn.logfile>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
<charset>UTF-8charset>
encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log.path}/${log.name}-warn-%d{yyyy-MM-dd}.%i.logfileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MBmaxFileSize>
timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>30maxHistory>
rollingPolicy>
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>warnlevel>
<onMatch>ACCEPTonMatch>
<onMismatch>DENYonMismatch>
filter>
appender>
<appender name="ERROR_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${log.path}/${log.name}_error.logfile>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
<charset>UTF-8charset>
encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log.path}/${log.name}-error-%d{yyyy-MM-dd}.%i.logfileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MBmaxFileSize>
timeBasedFileNamingAndTriggeringPolicy>
<maxHistory>30maxHistory>
rollingPolicy>
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>ERRORlevel>
<onMatch>ACCEPTonMatch>
<onMismatch>DENYonMismatch>
filter>
appender>
<root level="info">
<appender-ref ref="CONSOLE" />
<appender-ref ref="DEBUG_FILE" />
<appender-ref ref="INFO_FILE" />
<appender-ref ref="WARN_FILE" />
<appender-ref ref="ERROR_FILE" />
root>
configuration>
参考资料
spring boot --接入@SLF4J日志（二）日志配置详解