【Logback】＜configuration＞标签详解

阳光穿透心脏的1/2处 2024-03-24 16:44 27阅读 0赞

#### 文章目录 ####

*  一、Logback概述
 *  二、configuration属性
 *   *  2.1、使用示例
     *  2.2、参数说明
     *  2.3、解析
     *  2.4、示例
 *  三、configuration子节点
 *   *  3.1、configuration文件语法（节点配置）
     *  3.2、变量
     *   *  3.2.1、变量定义
         *  3.2.2、变量引用/使用
     *  3.3、＜logger＞、＜root＞详解
     *  3.4、＜appender＞节点
 *  四、参考资料

## 一、Logback概述 ##

logback是log4j的继承者，其分为三个模块：

<table> 
 <thead> 
  <tr> 
   <th>模块名</th> 
   <th align="left">说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>logback-core</td> 
   <td align="left">基础模块，可以在此模块的基础上构建自己的模块</td> 
  </tr> 
  <tr> 
   <td>logback-classic</td> 
   <td align="left">1、通化并升级改良log4j<br>2、实现<code>slf4j</code>的API，方便日志框架的切换</td> 
  </tr> 
  <tr> 
   <td>logback-access</td> 
   <td align="left">集成Servlet容器，提供HTTP访问日志的功能</td> 
  </tr> 
 </tbody> 
</table>

## 二、configuration属性 ##

### 2.1、使用示例 ###

### 2.2、参数说明 ###

<table> 
 <thead> 
  <tr> 
   <th>属性</th> 
   <th>可选值</th> 
   <th>说明</th> 
   <th>备注</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>scan</td> 
   <td><code>true</code>|<code>false</code></td> 
   <td>开启扫描，配置变更时logback自动更新配置</td> 
   <td>默认空，即false</td> 
  </tr> 
  <tr> 
   <td>scanPeriod</td> 
   <td>30 (|milli(second)?|second(e)?|minute|hour|day)s?</td> 
   <td>扫描间隔： 数字 + <code>空格</code> + 日期单位</td> 
   <td>默认<code>一分钟</code><br>若不指定时间单位，默认毫秒</td> 
  </tr> 
  <tr> 
   <td>debug</td> 
   <td><code>true</code>|<code>false</code></td> 
   <td>注册OnConsoleStatusListener的简写模式，控制台输出logback内部日志</td> 
   <td>默认<code>false</code></td> 
  </tr> 
  <tr> 
   <td>packagingData</td> 
   <td><code>true</code>|<code>false</code></td> 
   <td>每行日志都输出包信息其所在jar包信息</td> 
   <td>对性能影响较大，1.1.4及以上版本默认<code>false</code></td> 
  </tr> 
 </tbody> 
</table>

### 2.3、解析 ###

> scan源码：ch.qos.logback.classic.joran.action.ConfigurationAction

package ch.qos.logback.classic.joran.action;
    // ..............
    
    public class ConfigurationAction extends Action {
        
        static final String INTERNAL_DEBUG_ATTR = "debug";
        static final String PACKAGING_DATA_ATTR = "packagingData";
        static final String SCAN_ATTR = "scan";
        static final String SCAN_PERIOD_ATTR = "scanPeriod";
        
        // ....scan....
        void processScanAttrib(InterpretationContext ic, Attributes attributes) {
        
            String scanAttrib = ic.subst(attributes.getValue(SCAN_ATTR));
            // 
            if (!OptionHelper.isEmpty(scanAttrib) && !"false".equalsIgnoreCase(scanAttrib)) {
        
    
                ScheduledExecutorService scheduledExecutorService = context.getScheduledExecutorService();
                URL mainURL = ConfigurationWatchListUtil.getMainWatchURL(context);
                if (mainURL == null) {
        
                    addWarn("Due to missing top level configuration file, reconfiguration on change (configuration file scanning) cannot be done.");
                    return;
                }
                ReconfigureOnChangeTask rocTask = new ReconfigureOnChangeTask();
                rocTask.setContext(context);
    
                context.putObject(CoreConstants.RECONFIGURE_ON_CHANGE_TASK, rocTask);
    
                String scanPeriodAttrib = ic.subst(attributes.getValue(SCAN_PERIOD_ATTR));
                Duration duration = getDuration(scanAttrib, scanPeriodAttrib);
    
                if (duration == null) {
        
                    return;
                }
    
                addInfo("Will scan for changes in [" + mainURL + "] ");
                // Given that included files are encountered at a later phase, the complete list of files 
                // to scan can only be determined when the configuration is loaded in full.
                // However, scan can be active if mainURL is set. Otherwise, when changes are detected
                // the top level config file cannot be accessed.
                addInfo("Setting ReconfigureOnChangeTask scanning period to " + duration);
    
                ScheduledFuture<?> scheduledFuture = scheduledExecutorService.scheduleAtFixedRate(rocTask, duration.getMilliseconds(), duration.getMilliseconds(),
                                TimeUnit.MILLISECONDS);
                context.addScheduledFuture(scheduledFuture);
            }
        }
    
        // ........
    }

### 2.4、示例 ###

> `debug`=true ，示例

13:33:04.002  WARN --- [     http-nio-8080-exec-2] c.qbhj.logback.controller.LogController  : warn......warn......
    13:33:04.003  INFO --- [     http-nio-8080-exec-2] c.qbhj.logback.controller.LogController  : info......info......
    13:33:04.003 ERROR --- [     http-nio-8080-exec-2] c.qbhj.logback.controller.LogController  : error......error......error......
    
    ↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓   以下为debug=true输出的logback内部日志   ↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓
    13:33:04,003 |-INFO in c.q.l.co.rolling.helper.RenameUtil - Renaming file [logs\case-logback\case-springboot-logback.error.log] to [logs\case-logback\history\case-springboot-logback.error.2023-03-18-13-32.0.log59129593988100.tmp]
    13:33:04,005 |-INFO in ch.qos.logback.core.rolling.helper.Compressor - GZ compressing [logs\case-logback\history\case-springboot-logback.error.2023-03-18-13-32.0.log59129593988100.tmp] as [logs\case-logback\history\case-springboot-logback.error.2023-03-18-13-32.0.log.gz]
    13:33:04,006 |-INFO in c.q.l.core.rolling.helper.TimeBasedArchiveRemover - Removed  0 Bytes of files

> `packagingData`=true，示例如下：

14:28:48.835 [btpool0-7] INFO  c.q.l.demo.prime.PrimeAction - 99 is not a valid value
    java.lang.Exception: 99 is invalid
      at ch.qos.logback.demo.prime.PrimeAction.execute(PrimeAction.java:28) [classes/:na]
      at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) [struts-1.2.9.jar:1.2.9]
      at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) [struts-1.2.9.jar:1.2.9]
      at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432) [struts-1.2.9.jar:1.2.9]
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:820) [servlet-api-2.5-6.1.12.jar:6.1.12]
      at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:502) [jetty-6.1.12.jar:6.1.12]
      at ch.qos.logback.demo.UserServletFilter.doFilter(UserServletFilter.java:44) [classes/:na]
      at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1115) [jetty-6.1.12.jar:6.1.12]
      at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:361) [jetty-6.1.12.jar:6.1.12]
      at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:417) [jetty-6.1.12.jar:6.1.12]
      at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230) [jetty-6.1.12.jar:6.1.12]

日志最后展示日志输出类的包信息，如 `[struts-1.2.9.jar:1.2.9]`

## 三、configuration子节点 ##

### 3.1、configuration文件语法（节点配置） ###

如下（图片摘自官网）：  
![摘自官网][e551b44ac4204a75a32d641fed93e895.png]

### 3.2、变量 ###

#### 3.2.1、变量定义 ####

1.  语法：

> <property>  
> <variable>

低版本可以通过`<property>` 来定义，1.0.7版本后可以通过`<variable>`等同于`<property>`，二者一样

1.  使用示例：

<variable name="USER_HOME" value="/home/sebastien" />
    <property name="USER_HOME1" value="/home/sebastien" />
    
    <variable file="src/main/java/chapters/configuration/variables1.properties" />
    <variable resource="resource1.properties" />

#### 3.2.2、变量引用/使用 ####

1.  语法：

> 使用： $\{变量名\}
> 
> 指定默认值：以`:-` 分隔 `${name:-value}`

1.  示例：

<file>${USER_HOME}</file>
    
    <file>${USER_HOME:-default-user}</file>

### 3.3、＜logger＞、＜root＞详解 ###

见 [【Logback】＜logger＞、＜root＞标签详解][Logback_logger_root]

### 3.4、＜appender＞节点 ###

见 [【Logback】＜appender＞标签详解][Logback_appender]

## 四、参考资料 ##

[https://logback.qos.ch/manual/configuration.html][https_logback.qos.ch_manual_configuration.html]

[e551b44ac4204a75a32d641fed93e895.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/24/d2b1c2cd54ca4d16978e287166f2e72d.png
[Logback_logger_root]: https://editor.csdn.net/md/?articleId=129780600
[Logback_appender]: https://editor.csdn.net/md/?articleId=129909620
[https_logback.qos.ch_manual_configuration.html]: https://logback.qos.ch/manual/configuration.html