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How to set up two different log levels for two appenders via logback.xml in spring boot app?

I have some problem with logback.xml configuration. I want that console-appender write into console only info events and file-appender write into file with debug level.My current config looks like this :
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<property name="LOG_PATH" value="applogs"/>
<appender name="FILE_DAILY" class="ch.qos.logback.core.rolling.RollingFileAppender">
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<!-- daily rollover -->
<fileNamePattern>${LOG_PATH}/News_App_MRM.%d{yyyy-MM-dd}.log</fileNamePattern>
<!-- keep 30 days' worth of history capped at 3GB total size -->
<maxHistory>30</maxHistory>
<totalSizeCap>3GB</totalSizeCap>
</rollingPolicy>
<encoder>
<pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
</encoder>
</appender>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<!-- encoders are assigned the type
ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
<encoder>
<pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
</encoder>
</appender>
<root level="info">
<appender-ref ref="STDOUT"/>
<appender-ref ref="FILE_DAILY"/>
</root>
</configuration>

You have to define a logger like this
<logger name="org.hibernate" level="INFO" additivity="false">
<appender-ref ref="STDOUT"/>
</logger>
With this, all logs coming from org.hibernate will be logged on a INFO level.
You can then specify an appender for each logger.

Using logback, debug messages are still being logged though root level is set to "Error"

I have a project which has recently migrated from log4j to slf4j and logback. the root level is set to "Error", however, logs from third party libraries are still being logged at debug level.
Anyone has managed to solve this ?
Logback.xml :
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<appender name="FILE" class="ch.qos.logback.core.FileAppender" additivity="false">
<file>${catalina.home}/logs/database.log</file>
<encoder>
<pattern>%5p %d{HH:mm:ss}[%thread] %-5level %logger{5} - %msg%n</pattern>
</encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<FileNamePattern>logFile.%d{yyyy-MM-dd}.log</FileNamePattern>
</rollingPolicy>
</appender>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender" additivity="false">
<!-- encoders are assigned the type
ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
<encoder>
<pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{5} - %msg%n</pattern>
</encoder>
</appender>
<root level="ERROR">
<appender-ref ref="STDOUT" />
<appender-ref ref="FILE" />
</root>
</configuration>

Adding timestamp to a log file using Logback-test.xml

Currently my Spring-boot application logs to a file named: myLog.log, this is working as intended, however I would like the log file to have a timestamp at the end of it and create a new file each time it is ran.
I have tried to implement this in my logback-test.xml file shown below, but it is just giving me the filename: myLog.log without a timestamp.
How can I fix this?
Logback-test.xml:
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<include resource="org/springframework/boot/logging/logback/base.xml"/>
<logger name="org.springframework.web" level="INFO"/>
<!-- Send debug messages to System.out -->
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<!-- By default, encoders are assigned the type ch.qos.logback.classic.encoder.PatternLayoutEncoder -->
<encoder>
<pattern>%d{HH:mm:ss.SSS} - %msg%n</pattern>
</encoder>
</appender>
<appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>path/to/my/file/mylog.log</file>
<encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
<Pattern>%d{yyyy-MM-dd_HH:mm:ss.SSS} - %msg%n</Pattern>
</encoder>
<rollingPolicy class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy">
<FileNamePattern>mylog.%i{yyyy-MM-dd_HH:mm:ss.SSS}}.log</FileNamePattern>
<MinIndex>1</MinIndex>
<MaxIndex>10</MaxIndex>
</rollingPolicy>
<triggeringPolicy class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">
<MaxFileSize>2MB</MaxFileSize>
</triggeringPolicy>
</appender>
<logger name="com.my.package" level="INFO" additivity="false">
<appender-ref ref="STDOUT" />
<appender-ref ref="FILE" />
</logger>
<!-- By default, the level of the root level is set to DEBUG -->
<root level="INFO">
<appender-ref ref="STDOUT" />
</root>
</configuration>

You can define a variable like this:
<timestamp key="myTimestamp" datePattern="yyyy-MM-dd'_'HH-mm-ss.SSS"/>
(note: don't use colons in datePattern)
Then use it directly in your appender's file element:
<appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>path/to/my/file/mylog-${myTimestamp}.log</file>
...
</appender>
Or in a simple FileAppender:
<appender name="FILE" class="ch.qos.logback.core.FileAppender">
<file>path/to/my/file/mylog-${myTimestamp}.log</file>
<encoder>
<Pattern>%d{yyyy-MM-dd_HH:mm:ss.SSS} - %msg%n</Pattern>
</encoder>
</appender>

How to filter stacktrace frames in Logback

Say I have two Java classes: foo.ClassA and bar.ClassB. To print (root) exception stacktrace, I need to print only frames of foo package. My question is how exactly I can configure Logback to do that.
I know that the feature is already implemented in Logback, and I need to use evaluator. But I couldn't figure it out. I tried the example described here without success (no surprise).
Can anyone give the exact configuration for filtering stacktrace frames?
<configuration>
<evaluator name="FILTER">
<expression>¿what should I put here?</expression>
</evaluator>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>[%thread] %-5level - %msg%n%rEx{full, FILTER}</pattern>
</encoder>
</appender>
<root level="DEBUG">
<appender-ref ref="STDOUT" />
</root>
</configuration>

I contacted Tomasz Nurkiewicz (the author of the blog linked in the question) and he kindly answered my question. I'm posting the answer, just in case:
While printing stack trace, to filter lines from bar package use the following:
<configuration>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>[%thread] %-5level - %msg%n%rEx{full, bar}</pattern>
</encoder>
</appender>
...
</configuration>
I wanted to use it in my web application (Tomcat+Spring+Hibernate+etc). So I configured logback with the following not to print any stack trace line from org.something packages (e.g. org.apache, org.springframework, org.hibernate, etc):
<configuration>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>[%thread] %-5level - %msg%n%rEx{full, org}</pattern>
</encoder>
</appender>
...
</configuration>
Thanks Tomasz!

This may help someone who is writing springboot apps like me
I am currently using
<?xml version="1.0" encoding="UTF-8"?>
<configuration debug="true" packagingData="true">
<springProperty scope="context" name="APP_NAME" source="spring.application.name"/>
<include resource="org/springframework/boot/logging/logback/defaults.xml"/>
<springProfile name="!cloud">
<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>${APP_NAME} %green(%d{dd-MM-yyyy HH:mm:ss.SSS}) %magenta([%thread]) %highlight(%-5level) %red(%logger.%M:%L) - %magenta(%msg) %rEx{full,java.lang.reflect.Method,
org.apache.catalina,
org.apache.tomcat,
org.apache.coyote,
javax,
java.util.concurrent,
java.lang.Thread,
org.springframework.aop,
org.springframework.boot.actuate,
org.springframework.security,
org.springframework.transaction,
org.springframework.web,
sun.reflect,
net.sf.cglib,
ByCGLIB
}%n
</pattern>
</encoder>
</appender>
</springProfile>
<springProfile name="cloud">
<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<!-- send cloud event in one line so kibana can log it as one event -->
<pattern>%d{dd-MM-yyyy HH:mm:ss.SSS} [%thread] %-5level %logger.%M:%L - %msg %replace(%rEx){'[\r\n]+', '\\n'}%nopex %n</pattern>
</encoder>
</appender>
</springProfile>
<root level="INFO">
<appender-ref ref="CONSOLE"/>
</root>
<logger name="com.aaa" level="DEBUG"/>
<logger name="org.springframework.web.filter" level="INFO"/>
<logger name="org.springframework.cloud" level="INFO"/>
<logger name="org.springframework.core.env" level="INFO"/>
<logger name="org.springframework.boot" level="INFO"/>
<logger name="org.springframework.boot.actuate" level="WARN"/>
<logger name="org.springframework.boot.context" level="INFO"/>
<logger name="org.springframework.boot.autoconfigure" level="INFO"/>
<logger name="io.lettuce.core.protocol" level="WARN"/>

Logback to log different messages to two files

I am using logback/slf4j to do my logging. I want to parse my log file to analyze some data, so instead of parsing a great big file (mostly consisting of debug statements) I want to have two logger instances which each log to a separate file; one for analytics and one for all purpose logging. Does anyone know if this is possible with Logback, or any other logger for that matter?

It's very possible to do something like this in logback. Here's an example configuration:
<?xml version="1.0"?>
<configuration>
<appender name="FILE" class="ch.qos.logback.core.FileAppender">
<file>logfile.log</file>
<append>true</append>
<encoder>
<pattern>%-4relative [%thread] %-5level %logger{35} - %msg %n</pattern>
</encoder>
</appender>
<appender name="ANALYTICS-FILE" class="ch.qos.logback.core.FileAppender">
<file>analytics.log</file>
<append>true</append>
<encoder>
<pattern>%-4relative [%thread] %-5level %logger{35} - %msg %n</pattern>
</encoder>
</appender>
<!-- additivity=false ensures analytics data only goes to the analytics log -->
<logger name="analytics" level="DEBUG" additivity="false">
<appender-ref ref="ANALYTICS-FILE"/>
</logger>
<root>
<appender-ref ref="FILE"/>
</root>
</configuration>
Then you'd setup two separate loggers, one for everything and one to log analytics data like so:
Logger analytics = LoggerFactory.getLogger("analytics");

You can have as many loggers as you wish. But, it's better you have one for each package that you need to log differently. Then all the classes in that package and its sub-packages will get the that specific logger. They all can share the root logger and send their log data to root logger appender using additivity="true". Here's an example:
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<property name="pattern" value="%date{HH:mm:ss.SSS} %-5p %logger{36}
%X{akkaSource} [%file:%line] - %m%n" />
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>%date{HH:mm:ss.SSS} %-5p %logger{36} %X{akkaSource} [%file:%line] - %m%n</pattern>
</encoder>
</appender>
<appender name="abc" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${catalina.base}/logs/worker.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${catalina.base}/logs/worker-%d{yyyy-MM-dd_HH}.log</fileNamePattern>
<maxHistory>360</maxHistory>
</rollingPolicy>
<encoder>
<pattern>${pattern}</pattern>
</encoder>
</appender>
<appender name="xyz" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>${catalina.base}/logs/transformer.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${catalina.base}/logs/transformer-%d{yyyy-MM-dd_HH}.log</fileNamePattern>
<maxHistory>360</maxHistory>
</rollingPolicy>
<encoder>
<pattern>${pattern}</pattern>
</encoder>
</appender>
<logger name="com.xxx.yyy.zzz" level="INFO" additivity="true">
<appender-ref ref="xyz"/>
</logger>
<logger name="com.aaa.bbb.ccc" level="INFO" additivity="true">
<appender-ref ref="abc"/>
</logger>
<root>
<level value="INFO" />
<appender-ref ref="STDOUT" />
</root>

in my case I wanted to leave class names as log name
private static final Logger log = LoggerFactory.getLogger(ScheduledPost.class);
and as I had few such classes, so my logback.xml
<!--additivity=false ensures this log data only goes to the this log, and no one more -->
<logger name="xxx.xxx.xxx.ScheduledPost" level="DEBUG" additivity="false">
<appender-ref ref="ASYNC_SCHEDULE_LOG_FILE"/>
</logger>
<logger name="xxx.xxx.xxx.GcmPost" level="DEBUG" additivity="false">
<appender-ref ref="ASYNC_SCHEDULE_LOG_FILE"/>
</logger>
<logger name="xxx.xxx.xxx.PushUtils" level="DEBUG" additivity="false">
<appender-ref ref="ASYNC_SCHEDULE_LOG_FILE"/>
</logger>