【Logback】SpringBoot自动配置Logback全解

我会带着你远行 2024-03-24 16:48 66阅读 0赞

#### 文章目录 ####

*  一、Logback详解
 *  二、Spring Boot自动配置
 *   *  2.1、控制台输出
     *  2.2、配置文件名称
     *  2.3、配置文件加载顺序
     *  2.4、日志级别设置
     *  2.5、日志分组
     *   *  2.5.1、properties使用示例
         *  2.5.2、Spring Boot提供的默认分组
     *  2.4、Spring Boot自定义日志配置
     *  2.5、Spring Boot扩展xml变量引用标签
     *   *  2.5.1、Profile-specific Configuration使用示例
         *  2.5.2、Environment Properties使用示例
     *  2.6、自定义异常日志输出
     *   *  2.6.1、Spring Boot
         *  2.6.2、seata server
 *  三、参考资料

## 一、Logback详解 ##

如果对logback不了解，先参照以下三篇了解一下

1.  [【Logback】＜configuration＞标签详解][Logback_configuration]
2.  [【Logback】＜appender＞标签详解][Logback_appender]
3.  [【Logback】＜logger＞、＜root＞标签详解][Logback_logger_root]

## 二、Spring Boot自动配置 ##

Spring Boot默认是使用Logback的，并且提供了自动配置，以下对Spring Boot中Logback自动配置Starters的使用说明，基于Spring Boot `2.3.12.RELEASE`版本

### 2.1、控制台输出 ###

默认控制台输出 ERROR 、 WARN 和 INFO 级日志，可以配置来调整

1.  yml配置文件方式

debug: true
    # 或者
    # trace: true

1.  启动参数

通过启动参数 `--level`如`--debug`的方式来控制日志级别

java -jar myapp.jar --debug

> 源码： org.springframework.boot.context.logging.LoggingApplicationListener\#initializeEarlyLoggingLevel

private LogLevel springBootLogging = null;
    	
    	private void initializeEarlyLoggingLevel(ConfigurableEnvironment environment) {
        
    		if (this.parseArgs && this.springBootLogging == null) {
        
    			if (isSet(environment, "debug")) {
        
    				this.springBootLogging = LogLevel.DEBUG;
    			}
    			if (isSet(environment, "trace")) {
        
    				this.springBootLogging = LogLevel.TRACE;
    			}
    		}
    	}

### 2.2、配置文件名称 ###

> 默认加载名为：logback-spring.xml, logback-spring.groovy, logback.xml, or logback.groovy的配置文件

![在这里插入图片描述][108307ba5bb343bd8637fe79e6f55b91.png]

### 2.3、配置文件加载顺序 ###

> Spring的加载顺序：`logback.xml` \--> `application.properties` \--> `logback-spring.xml`  
> 注意：日志系统是在Spring上下文之前创建的，因此不能使用@PropertySource配置，建议使用 `logback-spring.xml`  
> 下文会讲到`<springProfile>`、`<springProperty>`标签和此有关系

![在这里插入图片描述][d399e82c56ce4d5584e1783bc26ec015.png]

### 2.4、日志级别设置 ###

> 语法： logging.level.<`logger-name`>=<`level`>

yml配置使用示例：

logging:
      level:
       root: warn  #root设置为warn级别
       org.springframework.web: debug  #name=org.springframework.web的logger设置为debug级别
       org.hibernate: error   #name=org.hibernate的logger设置为debug级别

### 2.5、日志分组 ###

可以把`<logger>`分组，通过组名来统一配置`<logger>`的设置

#### 2.5.1、properties使用示例 ####

# 将org.apache.catalina、org.apache.coyote、org.apache.tomcat三个logger设为tomcat组
    logging.group.tomcat=org.apache.catalina, org.apache.coyote, org.apache.tomcat
    # 将tomcat组的日志级别设置为 TRACE
    logging.level.tomcat=TRACE
    
    # 将sql组的日志级别设置为 DEBUG
    logging.level.sql=DEBUG

#### 2.5.2、Spring Boot提供的默认分组 ####

![35bea8c708924f179df0b2a4bfbbf66d.png][]

### 2.4、Spring Boot自定义日志配置 ###

<table> 
 <thead> 
  <tr> 
   <th align="left">Spring 环境变量</th> 
   <th align="left">系统变量（优先级高级Spring环境变量)</th> 
   <th align="left">说明</th> 
   <th align="left">默认</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">logging.exception-conversion-word</td> 
   <td align="left">LOG_EXCEPTION_CONVERSION_WORD</td> 
   <td align="left">异常日志转换字</td> 
   <td align="left"><code>%wEx</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.file.clean-history-on-start</td> 
   <td align="left">LOG_FILE_CLEAN_HISTORY_ON_START</td> 
   <td align="left">启动时清理归档日志</td> 
   <td align="left"><code>false</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.file.name</td> 
   <td align="left">LOG_FILE</td> 
   <td align="left">日志文件名称，可以是相对路径或者绝对路径</td> 
   <td align="left"><code>${LOG_FILE:-${LOG_PATH:-${LOG_TEMP:-${java.io.tmpdir:-/tmp}}}/spring.log}</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.file.path</td> 
   <td align="left">LOG_PATH</td> 
   <td align="left">日志文件路径</td> 
   <td align="left"></td> 
  </tr> 
  <tr> 
   <td align="left">logging.file.max-size</td> 
   <td align="left">LOG_FILE_MAX_SIZE</td> 
   <td align="left">日志文件最大容量（仅对logback有效）</td> 
   <td align="left"><code>10MB</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.file.max-history</td> 
   <td align="left">归档日志最大保留时间</td> 
   <td align="left">启动时清理归档日志</td> 
   <td align="left"><code>7</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.file.total-size-cap</td> 
   <td align="left">LOG_FILE_TOTAL_SIZE_CAP</td> 
   <td align="left">归档日志总计最大容量</td> 
   <td align="left"><code>0</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.pattern.console</td> 
   <td align="left">CONSOLE_LOG_PATTERN</td> 
   <td align="left">控制台日志格式</td> 
   <td align="left"><code>${CONSOLE_LOG_PATTERN:-%clr(%d{${LOG_DATEFORMAT_PATTERN:-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${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}}</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.pattern.dateformat</td> 
   <td align="left">LOG_DATEFORMAT_PATTERN</td> 
   <td align="left">Appender日期格式</td> 
   <td align="left"><code>yyyy-MM-dd HH:mm:ss.SSS</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.pattern.file</td> 
   <td align="left">FILE_LOG_PATTERN</td> 
   <td align="left">归档日志正则</td> 
   <td align="left"><code>${FILE_LOG_PATTERN:-%d{${LOG_DATEFORMAT_PATTERN:-yyyy-MM-dd HH:mm:ss.SSS}} ${LOG_LEVEL_PATTERN:-%5p} ${PID:- } --- [%t] %-40.40logger{39} : %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}}</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.pattern.level</td> 
   <td align="left">LOG_LEVEL_PATTERN</td> 
   <td align="left">日志级别</td> 
   <td align="left"><code>%5p</code></td> 
  </tr> 
  <tr> 
   <td align="left">logging.pattern.rolling-file-name</td> 
   <td align="left">ROLLING_FILE_NAME_PATTERN</td> 
   <td align="left">日志文件分片名称规则</td> 
   <td align="left"><code>${LOG_FILE}.%d{yyyy-MM-dd}.%i.gz</code></td> 
  </tr> 
  <tr> 
   <td align="left">PID</td> 
   <td align="left">PID</td> 
   <td align="left">当前进程</td> 
   <td align="left"></td> 
  </tr> 
 </tbody> 
</table>

> 默认值定义位置
> 
> 1.  org.springframework.boot.logging.logback.DefaultLogbackConfiguration
> 2.  org\\springframework\\boot\\spring-boot\\2.3.12.RELEASE\\spring-boot-2.3.12.RELEASE.jar!\\org\\springframework\\boot\\logging\\logback\\base.xml
> 3.  org\\springframework\\boot\\spring-boot\\2.3.12.RELEASE\\spring-boot-2.3.12.RELEASE.jar!\\org\\springframework\\boot\\logging\\logback\\defaults.xml
> 4.  org\\springframework\\boot\\spring-boot\\2.3.12.RELEASE\\spring-boot-2.3.12.RELEASE.jar!\\org\\springframework\\boot\\logging\\logback\\console-appender.xml
> 5.  org\\springframework\\boot\\spring-boot\\2.3.12.RELEASE\\spring-boot-2.3.12.RELEASE.jar!\\org\\springframework\\boot\\logging\\logback\\file-appender.xml

注意：

> xml中变量默认值按logback的语法： $\{name`:-`value\}  
> yml或者properties中使用默认值要按spel表达式 $\{name`:`value\}，没有`-`

![在这里插入图片描述][5e482d1a6d1a4eb29636fb14693d050d.png]

### 2.5、Spring Boot扩展xml变量引用标签 ###

> 源码：org.springframework.boot.logging.logback.SpringBootJoranConfigurator

class SpringBootJoranConfigurator extends JoranConfigurator {
        
    
    	private LoggingInitializationContext initializationContext;
    
    	SpringBootJoranConfigurator(LoggingInitializationContext initializationContext) {
        
    		this.initializationContext = initializationContext;
    	}
    
    	@Override
    	public void addInstanceRules(RuleStore rs) {
        
    		super.addInstanceRules(rs);
    		Environment environment = this.initializationContext.getEnvironment();
    		rs.addRule(new ElementSelector("configuration/springProperty"), new SpringPropertyAction(environment));
    		rs.addRule(new ElementSelector("*/springProfile"), new SpringProfileAction(environment));
    		rs.addRule(new ElementSelector("*/springProfile/*"), new NOPAction());
    	}
    }

#### 2.5.1、Profile-specific Configuration使用示例 ####

就是对`spring.profiles.active`的支持，支持某些配置在指定配置文件激活时才有效  
示例：

#### 2.5.2、Environment Properties使用示例 ####

支持在logback-spring.xml中通过`<springProperty>`引用`properties`或者`yml`中的环境变量  
示例：

<springProperty scope="context" name="fluentHost" source="myapp.fluentd.host"
            defaultValue="localhost"/>
    <appender name="FLUENT" class="ch.qos.logback.more.appenders.DataFluentAppender">
        <remoteHost>${fluentHost}</remoteHost>
        ...
    </appender>

<table> 
 <thead> 
  <tr> 
   <th align="left">属性名</th> 
   <th align="left">说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">scope</td> 
   <td align="left">变量范围</td> 
  </tr> 
  <tr> 
   <td align="left">name</td> 
   <td align="left">变量名（logback-spring.xml ）</td> 
  </tr> 
  <tr> 
   <td align="left">source</td> 
   <td align="left">spring环境变量中变量名</td> 
  </tr> 
  <tr> 
   <td align="left">defaultValue</td> 
   <td align="left">默认值</td> 
  </tr> 
 </tbody> 
</table>

### 2.6、自定义异常日志输出 ###

> 1、Spring Boot 提供了一个对异常日志转换器`WhitespaceThrowableProxyConverter`来自定义logback的异常处理，实现异常日志前后添加空行。  
> 2、Seata-server的源码对Spring Boot的`WhitespaceThrowableProxyConverter`又做了增强，添加了 `==>` `<==`配置

#### 2.6.1、Spring Boot ####

package org.springframework.boot.logging.logback;
    
    import ch.qos.logback.classic.pattern.ThrowableProxyConverter;
    import ch.qos.logback.classic.spi.IThrowableProxy;
    import ch.qos.logback.core.CoreConstants;
    
    /**
     * {@link ThrowableProxyConverter} that adds some additional whitespace around the stack
     * trace.
     *
     * @author Phillip Webb
     * @since 1.0.0
     */
    public class WhitespaceThrowableProxyConverter extends ThrowableProxyConverter {
        
    
    	@Override
    	protected String throwableProxyToString(IThrowableProxy tp) {
        
    		return CoreConstants.LINE_SEPARATOR + super.throwableProxyToString(tp) + CoreConstants.LINE_SEPARATOR;
    	}
    
    }

#### 2.6.2、seata server ####

1.  期望自定义格式：

> `==>`
> 
> 异常信息
> 
> `<==`

1.  代码实现，摘自 seata-server

package com.qbhj.logback.logback;
    
    import ch.qos.logback.classic.pattern.ExtendedThrowableProxyConverter;
    import ch.qos.logback.classic.spi.IThrowableProxy;
    import ch.qos.logback.core.CoreConstants;
    
    /**
     * 摘自 seata-server
     */
    public class ExtendedWhitespaceThrowableProxyConverter extends ExtendedThrowableProxyConverter {
        
    
        @Override
        protected String throwableProxyToString(IThrowableProxy tp) {
        
            return "==>" + CoreConstants.LINE_SEPARATOR + super.throwableProxyToString(tp)
                    + "<==" + CoreConstants.LINE_SEPARATOR + CoreConstants.LINE_SEPARATOR;
        }
    }

1.  使用

*  xml配置

<conversionRule conversionWord="wEx2" converterClass="com.qbhj.logback.logback.ExtendedWhitespaceThrowableProxyConverter"/>
    
    
    <springProperty name="FILE_LOG_PATTERN" source="logging.pattern.file" 
            defaultValue="%d{yyyy-MM-dd HH:mm:ss.SSS} %5p --- [%30.30t] %-40.40logger{39} : %m%n%wEx2"/>

*  java

/**
         * 自定义日志格式：异常转换
         */
        @GetMapping("/custom")
        public void customThrowableProxyConverter() {
        
            RuntimeException runtimeException = new RuntimeException("测试logback 异常！");
            log.error("logback自定义日志格式......", runtimeException);
        }

1.  效果演示

14:41:29.461  INFO --- [     http-nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 3 ms
    14:41:29.477 ERROR --- [     http-nio-8080-exec-1] c.qbhj.logback.controller.LogController  : logback自定义日志格式......
    ==>
    java.lang.RuntimeException: 测试logback 异常！
        at com.qbhj.logback.controller.LogController.customThrowableProxyConverter(LogController.java:46)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    
      。。。。。。
    
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
        at java.lang.Thread.run(Thread.java:748)
    <==

## 三、参考资料 ##

[https://docs.spring.io/spring-boot/docs/2.3.12.RELEASE/reference/html/spring-boot-features.html\#boot-features-logging][https_docs.spring.io_spring-boot_docs_2.3.12.RELEASE_reference_html_spring-boot-features.html_boot-features-logging]  
[https://gitee.com/mirrors/Seata/blob/2.x/server/src/main/java/io/seata/server/logging/logback/ExtendedWhitespaceThrowableProxyConverter.java][https_gitee.com_mirrors_Seata_blob_2.x_server_src_main_java_io_seata_server_logging_logback_ExtendedWhitespaceThrowableProxyConverter.java]

[Logback_configuration]: https://blog.csdn.net/weixin_43582081/article/details/130028301
[Logback_appender]: https://blog.csdn.net/weixin_43582081/article/details/129909620
[Logback_logger_root]: https://blog.csdn.net/weixin_43582081/article/details/129780600
[108307ba5bb343bd8637fe79e6f55b91.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/24/d1875d43f44246458a73fb10844675cf.png
[d399e82c56ce4d5584e1783bc26ec015.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/24/a275e1fb0eb84fbd9931ffa59c29d507.png
[35bea8c708924f179df0b2a4bfbbf66d.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/24/4326b790b38a48ac8bca05be7621bfaa.png
[5e482d1a6d1a4eb29636fb14693d050d.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/24/116b105dda40441484baf0a480e003a7.png
[https_docs.spring.io_spring-boot_docs_2.3.12.RELEASE_reference_html_spring-boot-features.html_boot-features-logging]: https://docs.spring.io/spring-boot/docs/2.3.12.RELEASE/reference/html/spring-boot-features.html#boot-features-logging
[https_gitee.com_mirrors_Seata_blob_2.x_server_src_main_java_io_seata_server_logging_logback_ExtendedWhitespaceThrowableProxyConverter.java]: https://gitee.com/mirrors/Seata/blob/2.x/server/src/main/java/io/seata/server/logging/logback/ExtendedWhitespaceThrowableProxyConverter.java