如何使用Spring BoneCPDataSource bean作为Log4j 2 JDBC appender的数据源？

Question

我想将log4j2消息记录到关系数据库中.

JDBC appender的文档在这里.我可以使用这些来源作为数据库连接提供者:

• 连接工厂
• 数据源
• DriverManager的

但是在某种程度上如何使用我们在整个应用程序中使用的数据源bean(com.jolbox.bonecp.BoneCPDataSource)？

Answer 1

您可以通过4个步骤完成(步骤2和3是针对Web应用程序的log4j2配置):

步骤1:创建log4j2.xml文件(不带JDBC appender)并将其放在WEB-INF文件夹中

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="INFO">

    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
        </Console>

    </Appenders>

    <Loggers>
        <Root level="info">
            <AppenderRef ref="Console"/>
        </Root>
    </Loggers>

</Configuration>

步骤2:将log4j2-web-2.x.jar添加到WEB-INF/lib.

这是maven存储库,您可以从那里下载jar,或者如果您使用maven,则将依赖项复制粘贴到您的pom.xml.

步骤3:根据servlet api版本配置web.xml

有关更多详细信息,请参阅log4j2 文档.以下是在servlet 2.5 Web应用程序中配置log4j的方法.

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
id="WebApp_ID" version="2.5">

<!-- Logg -->
<listener>
    <listener-class>org.apache.logging.log4j.web.Log4jServletContextListener</listener-class>
</listener>
<filter>
    <filter-name>log4jServletFilter</filter-name>
    <filter-class>org.apache.logging.log4j.web.Log4jServletFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>log4jServletFilter</filter-name>
    <url-pattern>/*</url-pattern>
    <dispatcher>REQUEST</dispatcher>
    <dispatcher>FORWARD</dispatcher>
    <dispatcher>INCLUDE</dispatcher>
    <dispatcher>ERROR</dispatcher>
</filter-mapping>
<!-- /Logg -->

<!-- ... -->
</web-app>

第4步:创建一个spring bean,注入你的DataSource bean,并在@PostConstruct方法中动态添加JDBC Appender配置

这是代码示例(使用log4j 2.1和spring 3.5进行测试)

import java.sql.Connection;
import java.sql.SQLException;

import javax.annotation.PostConstruct;
import javax.sql.DataSource;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.core.Appender;
import org.apache.logging.log4j.core.LoggerContext;
import org.apache.logging.log4j.core.appender.db.jdbc.ColumnConfig;
import org.apache.logging.log4j.core.appender.db.jdbc.ConnectionSource;
import org.apache.logging.log4j.core.appender.db.jdbc.JdbcAppender;
import org.apache.logging.log4j.core.config.AppenderRef;
import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.LoggerConfig;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;


@Component
public class LogUtils{

  @Autowired
  private DataSource dataSource;

  //inner class
  class Connect implements ConnectionSource {
    private DataSource dsource;
    public Connect(DataSource dsource) {
        this.dsource = dsource;
    }
    @Override
    public Connection getConnection() throws SQLException {
        return this.dsource.getConnection();
    }

  }

  public LogUtils() {
    System.out.println("LogUtils");     
  }

  @PostConstruct
  private void init(){
    System.out.println("init LogUtils");    
    final LoggerContext ctx = (LoggerContext) LogManager.getContext(false);
    final Configuration config = ctx.getConfiguration();
    ColumnConfig[] cc = {
            ColumnConfig.createColumnConfig(config, "date", null, null, "true", null, null),
            ColumnConfig.createColumnConfig(config, "level", "%level", null, null, null, null),
            ColumnConfig.createColumnConfig(config, "logger", "%logger", null, null, null, null),
            ColumnConfig.createColumnConfig(config, "message", "%message", null, null, null, null),
            ColumnConfig.createColumnConfig(config, "throwable", "%ex{short}", null, null, null, null),
            ColumnConfig.createColumnConfig(config, "salarie_id", "%X{SALARIE_ID}", null, null, null, null)
    } ;     
    Appender appender = JdbcAppender.createAppender("databaseAppender", "true", null, new Connect(dataSource), "0", "sicdb.bo_log", cc);
    appender.start();
    config.addAppender(appender);
    LoggerConfig loggerConfig = config.getLoggerConfig(LogManager.ROOT_LOGGER_NAME);
    loggerConfig.addAppender(appender, null, null);
    ctx.updateLoggers();        
  }

  public DataSource getDataSource() {
    return dataSource;
  }

  public void setDataSource(DataSource dataSource) {
    this.dataSource = dataSource;
  }


}

**限制:链接到doc**

应用程序有时需要自定义与实际配置分开的日志记录.Log4j允许这样做,尽管它受到一些限制:1.如果配置文件被更改,配置将被重新加载,手动更改将丢失.2.对运行配置的修改要求调用所有被调用的方法(addAppender和addLogger).因此,自定义配置的推荐方法是扩展其中一个标准配置类,重写安装方法以首先执行super.setup(),然后在注册之前将自定义Appenders,Filters和LoggerConfigs添加到配置中.使用.