Slf4j + logback logging framework

First introduce related dependencies （ Of course, many packages will indirectly rely on these dependencies ）

 <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.0</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-api -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.25</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.3</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter-api -->
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <version>5.2.0</version>
            <scope>test</scope>
        </dependency>

Use here Slf4j Why , There are many log frameworks on the market ,Slf4j It can be regarded as an interface or similar jdbc, Integrate different logging frameworks , It is convenient for us to change the logging framework in a project , It can be well maintained . Here we are using Slf4j + logback The way .

in addition ,Slf4j Placeholders are used for log output ｛｝ The way , Compared with other logging frameworks, it can avoid many performance problems caused by string splicing .

Next, let's talk about logback The problem with the configuration file ：

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

<!-- scan:-->
<!--  When this property is set to true when , If the configuration file changes , Will be reloaded , The default value is true.-->
<!-- scanPeriod:-->
<!--  Set the time interval between changes in the monitoring profile , If no time unit is given , The default unit is milliseconds . When scan by true when , This property takes effect . The default time interval is 1 minute .-->
<!-- debug:-->
<!--  When this property is set to true when , Will print out logback Internal log information , Real-time view logback Running state . The default value is false.-->
<configuration scan="true" scanPeriod="10 seconds">

    <contextName>austin</contextName>

    <!--  Set log output path   You can make “${}” To use variables .TODO  The configuration can be read later  -->
    <property name="log.path" value="logs"/>

    <springProperty scope="context" name="grayLogIp" source="austin.business.graylog.ip"/>


<!--  In a configuration There can be more than one appender appender Mainly specify the output destination   Which attribute name Used to specify self-defined names  class Used to specify the destination of the output -->
<!-- ch.qos.logback.core.ConsoleAppender  The output of the console -->
<!-- ch.qos.logback.core.rolling.RollingFileAppender  File scrolling output ： Now write the log to a file , Under certain conditions , Output some logs to another file -->
    <appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <!-- Format output ：%d Indicates the date ,%thread Represents the thread name ,%-5level： The level is shown from the left 5 Character width %msg： Log message ,%n Is a newline -->
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%n</pattern>
            <!--  Set character set  -->
            <charset>UTF-8</charset>
        </encoder>
    </appender>


<!-- file The file path of the log output , It can be absolute path or relative path -->
<!-- encoder Formatting method -->
<!-- rollingPolicy Rolling strategy   through class To specify the scrolling strategy -->
<!--  The most common scrolling strategy is   Time based rolling strategy  ch.qos.logback.core.rolling.TimeBasedRollingPolicy-->

<!-- fileNamePattern Used to refer to the file name format of the produced rolling log -->
<!-- Time scrolling means that the generated log will not only be printed in one file , It will be printed into different files with a certain order according to a certain strategy -->
   <!--  Time scrolling output  level by  INFO  journal  -->
    <appender name="INFO_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <!--  The path and filename of the log file being logged  -->
        <file>${log.path}/austin-info.log</file>
        <!-- Log file output format -->
        <encoder>
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%n</pattern>
            <charset>UTF-8</charset>
        </encoder>
        <!--  Rolling policy for loggers , By date , Record by size  -->
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <!--  Daily log archive path and format  -->
            <fileNamePattern>${log.path}/logs/austin-info-%d{yyyy-MM-dd}.%i.log</fileNamePattern>

<!--  When more than 1000MB when , Trigger scrolling strategy -->
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>1000MB</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
            <!-- Log file retention days -->
            <maxHistory>15</maxHistory>
        </rollingPolicy>
        <!--  This log file only records info Grade  -->
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>info</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>DENY</onMismatch>
        </filter>
    </appender>

    <!--  Time scrolling output  level by  ERROR  journal  -->
    <appender name="ERROR_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <!--  The path and filename of the log file being logged  -->
        <file>${log.path}/austin-error.log</file>
        <!-- Log file output format -->
        <encoder>
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%n</pattern>
            <charset>UTF-8</charset> <!--  Set character set here  -->
        </encoder>
        <!--  Rolling policy for loggers , By date , Record by size  -->
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <fileNamePattern>${log.path}/logs/austin-error-%d{yyyy-MM-dd}.%i.log</fileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>1000MB</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
            <!-- Log file retention days -->
            <maxHistory>15</maxHistory>
        </rollingPolicy>
        <!--  This log file only records ERROR Grade  -->
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>ERROR</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>DENY</onMismatch>
        </filter>
    </appender>

    <appender name="GELF" class="de.siegmar.logbackgelf.GelfUdpAppender">
        <!-- Graylog Address of service  -->
        <graylogHost>${grayLogIp}</graylogHost>
        <!-- UDP Input port  -->
        <graylogPort>12201</graylogPort>
        <!--  Maximum GELF Block size （ Company ： byte ）,508 Is the recommended minimum , The maximum value is 65467 -->
        <maxChunkSize>508</maxChunkSize>
        <!--  Use compression  -->
        <useCompression>true</useCompression>
        <encoder class="de.siegmar.logbackgelf.GelfEncoder">
            <!--  Whether to send native log information  -->
            <includeRawMessage>false</includeRawMessage>
            <includeMarker>true</includeMarker>
            <includeMdcData>true</includeMdcData>
            <includeCallerData>false</includeCallerData>
            <includeRootCauseData>false</includeRootCauseData>
            <!--  Whether to send the name of the log level , Otherwise, the log level is represented by a number by default  -->
            <includeLevelName>true</includeLevelName>
            <shortPatternLayout class="ch.qos.logback.classic.PatternLayout">
                <pattern>%m%nopex</pattern>
            </shortPatternLayout>
            <fullPatternLayout class="ch.qos.logback.classic.PatternLayout">
                <pattern>%d - [%thread] %-5level %logger{35} - %msg%n</pattern>
            </fullPatternLayout>

            <!--  Configuration application name （ The service name ）, adopt staticField The tag can customize some fixed log fields  -->
            <staticField>app_name:austin</staticField>
        </encoder>
    </appender>

    <root level="info">
        <!-- TODO console You can print only for dev Environmental  -->
        <appender-ref ref="CONSOLE"/>
        <appender-ref ref="INFO_FILE"/>
        <appender-ref ref="ERROR_FILE"/>
        <appender-ref ref="GELF"/>
    </root>

</configuration>

When spring When loading, it will automatically go to the path to find logback.xml The name of the file and load the configuration

Use

@Slf4j
class UserServiceImpl{
    
	public void deleteUser(int id){
    
		log.info(" Pass in id by ｛｝",id);
		}
}

@Slf4j yes Lombok Annotations , Instead of the sentence

Logger log=LoggerFactory.getLogger();