Log4j set a different logging level for each appender - java

I'm using Log4j 2 to log the events of my application. However I'm stuck at the following problem.
Currently all logging messages are being written to two different appenders. One has RollingFile type, while the other has Console type.
What I want is for the RollingFile appender to log messages with an INFO level or higher (ERROR, FATAL), and for the Console appender to log messages with an ERROR level or higher (FATAL).
Inside my log4j2.xml file I seem to be only able to declare the logging level for an entire logger (including all of its appenders). Here is my log4j2.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration monitorInterval="30">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout>
<Pattern>%d %level %msg%n</Pattern>
</PatternLayout>
</Console>
<RollingFile name="Log" fileName="log/Log.log" filePattern="log/Log-%d{yyyy-MM-dd}-%i.log" append="false">
<PatternLayout>
<Pattern>%d %level %msg%n</Pattern>
</PatternLayout>
<Policies>
<SizeBasedTriggeringPolicy size="1 MB" />
</Policies>
<DefaultRolloverStrategy max="10"/>
</RollingFile>
</Appenders>
<Loggers>
<Root level="info">
<AppenderRef ref="Console" />
<AppenderRef ref="Log" />
</Root>
</Loggers>
</Configuration>
Is there an easy way of doing so? I searched log4j documentation but couldn't find what I was looking for (Maybe I missed it?). If it's possible I would really prefer for the solution to be applicable on any appenders' types; not specific for RollingFile and Console.
EDIT:
I saw many questions where it was asked to write ONLY the messages from a certain level to a file, while writing the messages from a different level to a different file. In my case I need the messages with a certain level of HIGHER to be written to different files. For example in the case I provided messages with level ERROR or FATAL will be written to both the RollingFile and Console, while messages with level INFO will be written to RollingFile only.

To limit logging level on specific appender in log4j2 you should use ThresholdFilter element of an appender.
In your case log4j2.xml file will look like:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration monitorInterval="30">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<ThresholdFilter level="ERROR" onMatch="ACCEPT" onMismatch="DENY"/>
<PatternLayout>
<Pattern>%d %level %msg%n</Pattern>
</PatternLayout>
</Console>
<RollingFile name="Log" fileName="log/Log.log" filePattern="log/Log-%d{yyyy-MM-dd}-%i.log" append="false">
<ThresholdFilter level="INFO" onMatch="ACCEPT" onMismatch="DENY"/>
<PatternLayout>
<Pattern>%d %level %msg%n</Pattern>
</PatternLayout>
<Policies>
<SizeBasedTriggeringPolicy size="1 MB" />
</Policies>
<DefaultRolloverStrategy max="10"/>
</RollingFile>
</Appenders>
<Loggers>
<Root level="info">
<AppenderRef ref="Console" />
<AppenderRef ref="Log" />
</Root>
</Loggers>
</Configuration>
Here is a simple test:
public class Log4jTest {
private static final Logger logger = LogManager.getLogger(Log4jTest.class);
public static void main(String[] args) {
logger.debug("Debug");
logger.info("Info");
logger.warn("Warning");
logger.error("Error");
logger.fatal("Fatal");
}
}
Console output:
2020-02-25 12:33:50,587 ERROR Error
2020-02-25 12:33:50,589 FATAL Fatal
Log.log contents:
2020-02-25 12:33:50,585 INFO Info
2020-02-25 12:33:50,587 WARN Warning
2020-02-25 12:33:50,587 ERROR Error
2020-02-25 12:33:50,589 FATAL Fatal
In first version of log4j it was Threshold property of appender. On how to solve the same in log4j see the answer on question.
With aid of filters Log4j2 allows to configure the output to a specific appender much more flexible then log4j.

This should do the trick.
<Loggers>
<Root level="debug" additivity="false">
<AppenderRef ref="Console"/>
</Root>
<Logger name="com.project.package" level="info" additivity="false">
<AppenderRef ref="Log" />
</Logger>
</Loggers>
Alternatively, you could do it like this - Different level of logs in different log files
BTW, this is explained very nicely in the Log4j2 documentation. See - https://logging.apache.org/log4j/2.x/manual/configuration.html

Related

How to use JMSAppender log4j2 JAVA

I'm trying to push logs to an ActiveMqueue using JMS in log4j2.
I have done this in my log4j2.properites
<?xml version="1.0" encoding="UTF-8"?>
<Configuration monitorInterval="5">
<Appenders>
<RollingFile name="fishLogstash"
fileName="E:/xxx/log/xxx.server/xxxLogstash.log" append="false"
immediateFlush="false" bufferSize="1000"
filePattern="/soft/log/xxx.server/xxxx-%i.log">
<PatternLayout pattern="%-d{yyyy-MM-dd HH:mm:ss.SSS} %5p %c{1} - %m%n" />
<Policies>
<SizeBasedTriggeringPolicy size="100M" />
</Policies>
<DefaultRolloverStrategy max="10" />
</RollingFile>
<JMS name="jmsQueue" destinationBindingName="logQueue"
factoryName="org.apache.activemq.jndi.ActiveMQInitialContextFactory"
factoryBindingName="ConnectionFactory"
providerURL="tcp://localhost:61616">
<PatternLayout pattern="%-d{yyyy-MM-dd HH:mm:ss.SSS} %5p %c{1} - %m%n" />
</JMS>
</Appenders>
<Loggers>
<Root level="warn">
<AppenderRef ref="fish" />
</Root>
</Loggers>
</Configuration>
After this, I wonder how to use the JMS appender to log in my java code? How to retrieve this specific appender, is there somthing like
Logger log = Logger.getAppender("jmsQueue") ?
Thanks in advance.
1.
In your property file, there are xml content. So I am assuming you are trying to use xml style property file. If so, rename your property file to have .xml extension. E.g. log4j2.xml. Remember to write log4j2 supported xml. Examples can be found here.
2.
Mention name value of your defined appenders as AppenderRef in Loggers section of property file. Based on your Appenders section, Loggers section can be
<Loggers>
<Logger name="jmsLogger" level="warn">
<AppenderRef ref="jmsQueue" />
</Logger>
<Root level="warn">
<AppenderRef ref="fishLogstash" />
</Root>
</Loggers>
3.
In your code, get JMS logger as follows:
Logger log = LogManager.getLogger("jmsLogger");
You can log whatever by using log variable. E.g.
log.info("some message");
Hope, this answer would help you.

How to write logs to two different loggers?

Im able to create two logs using log4j2 and im able to write the log to a single log file. how to write logs to a two different loggers?
i modified the log4j2.xml file to have two loggers.
Any sample example?
Instead of configuring multiple loggers, you may want to configure multiple appenders. Example:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="warn">
<Appenders>
<File name="MyFile" fileName="logs/app.log">
<PatternLayout>
<Pattern>%d %p %c{1.} [%t] %m%n</Pattern>
</PatternLayout>
</File>
<File name="Other" fileName="logs/other.log">
<PatternLayout>
<Pattern>%d %p %c{1.} [%t] %m%n</Pattern>
</PatternLayout>
</File>
</Appenders>
<Loggers>
<Root level="trace">
<AppenderRef ref="MyFile" level="trace"/>
<AppenderRef ref="Other" level="debug"/>
</Root>
</Loggers>
</Configuration>
Point 1
I guess you're asking to write one log into different destinations, ex. different files. As Remko has mentioned, you could configure different appenders to handle each of the log file.
As I don't have enough reputations for commenting Remko's answer, here're some of my additional examples:
If you use the level of DEBUG for your logs, calling logger.debug("your message") and configure your log4j2.xml like the below, you'll see "your message" logged in both file1.log and file2.log.
<?xml version="1.0" encoding="UTF-8"?>
<Configuration>
<Appenders>
<File name="File1" fileName="logs/file1.log">
<PatternLayout>
<Pattern>"Add your pattern here"</Pattern>
</PatternLayout>
</File>
<File name="File2" fileName="logs/file2.log">
<PatternLayout>
<Pattern>"Add your pattern here"</Pattern>
</PatternLayout>
</File>
</Appenders>
<Loggers>
<Root level="debug">
<!--This will write the same log into both of the files -->
<AppenderRef ref="File1" level="debug"/>
<AppenderRef ref="File2" level="debug"/>
</Root>
</Loggers>
</Configuration>
Point 2
we should notice that, in Remko's example, all logs go into Other will also be written into MyFile. See more in Log4j2 Documentation, example 6 for explaination. In short, as TRACE is a lower lever than DEBUG, all logs with DEBUG levels could be passed in TRACE and logged.
Point 3
Another possibility of writing into different destinations is through Appender Additivity.
Each enabled logging request for a given logger will be forwarded to
all the apprenders in that Logger's LoggerConfig as well as the
Apprenders of the LoggerConfig's parents.

issue with my log4j2 setup

I was using log4j2 and it was logging statements for me with no issues. I might have made some changes (moved from info to debug and back) but its quite possibly I might have messed up the config in some other fashion. I am copying my config file below (I have not moved any log4j2 and slf4j jar files from my project). Any thoughts?
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="debug" name="TestApp" packages="">
<Appenders>
<RollingRandomAccessFile name="RollingRandomAccessFile" fileName="logs/test.log" immediateFlush="false" append="false"
filePattern="logs/$${date:yyyy-MM}/app-%d{MM-dd-yyyy}-%i.log.gz">
<PatternLayout>
<Pattern>%d %p %c{1.} [%t] %m %ex%n</Pattern>
</PatternLayout>
<Policies>
<TimeBasedTriggeringPolicy />
<SizeBasedTriggeringPolicy size="500 MB"/>
</Policies>
</RollingRandomAccessFile>
</Appenders>
<Loggers>
<AsyncLogger name="FATAL_LOGGER" level="fatal" includeLocation="true" additivity="false">
<AppenderRef ref="RollingRandomAccessFile"/>
</AsyncLogger>
<Root level="debug" includeLocation="false">
<AppenderRef ref="RollingRandomAccessFile"/>
</Root>
</Loggers>
</Configuration>
I tested the config in a test project and it works without any issues. Ensure that you do not have any locks on the file and have correct read/write privileges on the file/directory.

Log4j2 auto config

I have a problem applying the log4j2.xml auto configuration properly, and I think it has something to do with my folder arrangement.
I'm using maven to add log4j2 libs and arrange my projects as follows:
- one project to contain all "common" classes, used by server and client side of my system.
- another "core" project - the server side application.
Both projects use the same general package hierarchy (like com.foo.specific.package)
In the Common project I define a logger wrapper:
public class LogWrapper
{
static Logger systemParentLogger = LogManager.getLogger("com.foo");
public static Logger getLogger(Class<?> cls)
{
return LogManager.getLogger(cls.getName());
}
}
Moreover, the Common project contains the log4j2.xml file under META-INF (alongside the persistence.xml file for Hibernate usage).
<?xml version="1.0" encoding="UTF-8"?>
<configuration name="PRODUCTION" status="OFF">
<appenders>
<appender type="RollingFile"
name="MyFileAppender"
fileName="logs/app.log"
filePattern="logs/$${date:yyyy-MM}/app-%d{MM-dd-yyyy}-%i.log.gz">
<layout type="PatternLayout" pattern="%d %p %C{1.} [%t] %m%n"/>
</appender>
</appenders>
<loggers>
<root level="error">
<appender-ref ref="MyFileAppender"/>
</root>
<logger name="com.foo" level="info" additivity="false">
<appender-ref ref="MyFileAppender"/>
</logger>
<logger name="org.hibernate" level="error">
<appender-ref ref=MyFileAppender"/>
</logger>
</loggers>
</configuration>
While running a sample code in the Core project (using the LogWrapper I wrote and some JPA voodoo), I could still see INFO hibernate logs, and no log file was created. I should state that while debugging the code, I could see that the logger fetched was given some weird value "com.foo.core.persistence.PersistenceXMLTest:ERROR in sun.misc.Launcher$AppClassLoader#2f600492"
The log4j2.xml was placed in a "Folder" which in eclipse terms is "not on classpath".
Changing META-INF to be a "source folder" solved the problem.
In addition, the log4j2.xml file was not defined properly.
These are the modifications needed:
<?xml version="1.0" encoding="UTF-8"?>
<configuration name="PRODUCTION" status="OFF">
<appenders>
<RollingFile name="MyFileAppender"
fileName="../Logs/app.log"
filePattern="../Logs/$${date:yyyy-MM}/app-%d{MM-dd-yyyy}-%i.log.gz">
<PatternLayout>
<pattern>%d %p %C{1.} [%t] %m%n</pattern>
</PatternLayout>
<Policies>
<OnStartupTriggeringPolicy />
<TimeBasedTriggeringPolicy interval="6" modulate="true"/>
<SizeBasedTriggeringPolicy size="250 MB"/>
</Policies>
</RollingFile>
</appenders>
<loggers>
<root level="error">
<appender-ref ref="MyFileAppender"/>
</root>
<logger name="com.foo" level="info" additivity="false">
<appender-ref ref="MyFileAppender"/>
</logger>
</loggers>
</configuration>
Still couldn't make the org.hibernate logger to be redirected to my logs, but at least I got the logger to work

Log4j2 saving file (using RollingFile appender)

I am trying log4j2 to create log file to the system I am developing right, I have followed the instruction on their site and there is no error occurred when I run it, but the log is not saved on where I set it (ex. "D:\logs\app.log").
Here is My log4j.xml
<?xml version="1.0" encoding="UTF-8"?>
<configuration status="OFF">
<appenders>
<RollingFile name="MyRollingFile" fileName="D:/logs/app.log"
filePattern="logs/$${date:yyyy-MM}/app-%d{MM-dd-yyyy}-%i.log.gz">
<PatternLayout>
<pattern>%d %p %C{1.} [%t] %m%n</pattern>
</PatternLayout>
<Policies>
<TimeBasedTriggeringPolicy />
<SizeBasedTriggeringPolicy size="250 MB"/>
</Policies>
<DefaultRolloverStrategy max="20"/>
</RollingFile>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
</Console>
</appenders>
<loggers>
<logger name="Log_RollingFile" level="TRACE" additivity="false">
<appender-ref ref="MyRollingFile"/>
</logger>
<root level="ERROR">
<appender-ref ref="Console"/>
</root>
</loggers>
</configuration>
I tried to :
delete app.log to see if my configuration (D:\logs\app.log) works. When I run the application it creates app.log so I think it means that it sees the configuration and the only thing is it is NOT SAVING the log.info that I did in java application
Change root level to "TRACE", and it prints the log.info.
[EDIT:]
I have also these libraries on my classpath
log4j-api-2.0-beta3.jar
log4j-core-2.0-beta3.jar
Am I missing something on RollingFile configuration or a library (maybe)?
Thanks in advance.
Your logger name is incorrect.
As explained in the configuration instructions you linked to, the logger should be named according to the package/classes you wish to capture logging for.
In their example the logger named com.foo.Bar would log everything from the Bar class in package com.foo with TRACE level.

Categories

Resources