GELF log4j appender for log4j version 1 and 2.

This is library for appender to Graylog2 server in GELF format (http://docs.graylog.org/en/2.2/pages/gelf.html).

Configuration

1. graylogHost - hostname of Graylog server. In format 'protocol:hostname'. At this moment only UDP and TCP are supported. Example: tcp:localhost
2. port - Graylog server listen port. In case not set default 12201 will be used.
3. blocking - true in case old blocking IO must be used. Default is false.
4. soTimeout - socket timeout in milliseconds in case blocking set to true. Default: 2000
5. facility - facility used for logging. Default : gelf4j-appender
6. logExceptions - true in case exception must be logged as full_message. Default: true
7. logThread - true in case execution thread must be logged as separate field. Default: true
8. logLine - true in case execution line must be logged as separate field. Default: false
9. logFile - true in case execution file must be logged as separate field. Default: false
10. logMethod - true in case execution method must be logged as separate field. Default: false
11. logClass - true in case execution class must be logged as separate field. Default: false
12. logLogger - true in case logger name must be logged as separate field. Default: false
13. logMdcValues - true in case MDC fields must be logged each as separate field. Default: false
14. sendBufferSize - send buffer size in bytes in case non blocking IO used. Default -1 - means use system defaults.
15. useCompression - true in case GZIP compression for UDP packets will be used. Default: false
16. compressionLevel - compression level of the package. Default : 5
17. compressionLimit - mininum size of payload to apply compression. Default : 8192
18. useCircuitBreaker - true in case Circuit breaker must be used to minimize IO operations in case lost of failures.
19. failuresToOpen - number of IO failures needed to open circuit breaker.
20. secondsToRecover - seconds to recover after failures.

Log4j 1.2

Appender for log4j version 1.2 is

  org.graylog2.gelf4j.appenders.Log4jGelfAppender

Example configuration looks like

log4j.rootLogger=DEBUG, gelf_appender

log4j.appender.gelf_appender=org.graylog2.gelf4j.appenders.Log4jGelfAppender
log4j.appender.gelf_appender.graylogHost=tcp:localhost
log4j.appender.gelf_appender.blocking=true
log4j.appender.gelf_appender.useCircuitBreaker=true
log4j.appender.gelf_appender.useCompression=true
log4j.appender.gelf_appender.layout=org.apache.log4j.PatternLayout
log4j.appender.gelf_appender.layout.ConversionPattern=%p %d{MMdd-HHmm:ss,SSS} %-4r [%t] \
  [%X{process}] %c{1} - %m%n

Log4j version 2.8

Appender for log4j version 2.8 is

org.graylog2.gelf4j.appenders.Log4j2GelfAppender

Note!

Hostname in version 2.8 must be set without connection type. Use type of the protocol as :

1. type - connection type. One of tcp or udp.

Example configuration looks like

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="INFO">
    <Appenders>
        <Gelf4j2 name="syslogtest" hostname="localhost" type="tcp">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
            <KeyValuePair key="additionalField1" value="additional value 1"/>
        </Gelf4j2>
    </Appenders>
    <Loggers>
        <Root level="info">
            <AppenderRef ref="syslogtest"/>
        </Root>
    </Loggers>
</Configuration>