日志总结

一、日志pattern规范

log4j2：　　　

　　错误实例：%d{yyyy-MM-dd HH:mm:ss.SSS} [%X{requestId}] %-5level | %logger{1.}:%line - %msg%n

　　正确实例：%d{yyyy-MM-dd HH:mm:ss,SSS} | %level | %logger{1.} - %X{requestId} -> %msg%n

错误点：
1. 去掉 -5level 中的-5,否则 kibana解析不了level
2. logger{1.}:%line 中，去掉:%line,否则kibana解析不了class
3. 将 {requestId} 放到 - 号后边，否则 message中查找不到该标识。

logback：　　%d{ISO8601} | %p | %logger{20} - [%thread] %msg%n

log4j：　　　 %d{ISO8601} | %p | %C - [%thread] %m%n

注意：- 后一定留个空格。-后放啥都行。

输出格式：2019-07-01 10:55:33,794 | INFO | com.ebc.log4j2.test.TestLog4j2 - [main] this is demo.

log4j2的缩写包名：http://logging.apache.org/log4j/2.x/manual/layouts.html

二、例子

1、log4j2

pom.xml

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
    <exclusions>
        <exclusion>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>
<!--当spring-boot-starter-web时，需要加入以下的log4j-web依赖-->
<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-web</artifactId>
</dependency>
<!-- 异步日志 -->
<dependency>
    <groupId>com.lmax</groupId>
    <artifactId>disruptor</artifactId>
    <version>3.4.2</version>
</dependency>

log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="INFO">
    <Appenders>
        <Console name="LogToConsole" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%X{requestId}] %-5level | %logger{1.}:%line - %msg%n"/>
            <!--<PatternLayout pattern="%d{HH:mm:ss,SSS}:%4p(%F:%L) - %m%n"/>-->
        </Console>
        <!--生产中，使用了ELK，不用使用以下LogToFile-->
        <File name="LogToFile" fileName="logs/app.log">
            <PatternLayout>
                <Pattern>%d %p %c{1.} [%t] %m%n</Pattern>
            </PatternLayout>
        </File>
    </Appenders>
    <Loggers>
        <Logger name="com.ebc" level="info" additivity="false">
            <AppenderRef ref="LogToFile"/>
            <AppenderRef ref="LogToConsole"/>
        </Logger>
        <Logger name="org.springframework.boot" level="error" additivity="false">
            <AppenderRef ref="LogToConsole"/>
        </Logger>
        <Root level="error">
            <AppenderRef ref="LogToFile"/>
            <AppenderRef ref="LogToConsole"/>
        </Root>
    </Loggers>
</Configuration>

执行异步日志：

$ java -Dlog4j2.contextSelector=org.apache.logging.log4j.core.async.AsyncLoggerContextSelector -jar target/logging-log4j2-1.0.jar

2、logback

pom.xml

<!-- Logback -->
<dependency>
    <groupId>ch.qos.logback</groupId>
    <artifactId>logback-core</artifactId>
    <version>1.1.2</version>
</dependency>
<dependency>
    <groupId>ch.qos.logback</groupId>
    <artifactId>logback-classic</artifactId>
    <version>1.1.2</version>
</dependency>
<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>1.7.8</version>
</dependency>
<!-- -->
<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>jcl-over-slf4j</artifactId>
    <version>1.7.8</version>
</dependency>

logback.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration debug="false">

    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>%d{ISO8601} | %p | %logger{20} - [%thread] %msg%n</pattern>
        </encoder>
    </appender>
    
    <!-- TRACE < DEBUG < INFO < WARN < ERROR -->
    <root level="INFO">
        <appender-ref ref="console"/>
    </root>
</configuration>

3、log4j

pom.xml

<dependency>
    <groupId>log4j</groupId>
    <artifactId>log4j</artifactId>
    <version>1.2.16</version>
</dependency>
<dependency>
    <groupId>log4j</groupId>
    <artifactId>apache-log4j-extras</artifactId>
    <version>1.1</version>
</dependency>
<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>1.6.2</version>
</dependency>
<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-log4j12</artifactId>
    <version>1.6.2</version>
</dependency>

log4j.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<log4j:configuration debug="true"
    xmlns:log4j='http://jakarta.apache.org/log4j/'>

    <appender name="console" class="org.apache.log4j.ConsoleAppender">
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%d{ISO8601} | %p | %C - [%thread] %m%n" />
        </layout>
    </appender>

    <!-- DEBUG < INFO < WARN < ERROR 没有定义的logger将会使用root logger -->
    <root>
        <priority value="INFO" />
        <appender-ref ref="console" />
    </root>

</log4j:configuration>