Logstash appender for dropwizard : this generates a logstash compatible log file that can be synced using the logstash-forwarder

application.yaml

    - type: logstashfile
      currentLogFilename: /melodis/logs/UserDataStorage/logstash/logstash.log
      threshold: ALL
      archive: true
      archivedLogFilenamePattern: /melodis/logs/UserDataStorage/logstash/logstash-%d.log
      archivedFileCount: 48
      timeZone: UTC

LogstashAppender.java

import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.core.Appender;
import ch.qos.logback.core.FileAppender;
import ch.qos.logback.core.Layout;
import com.fasterxml.jackson.annotation.JsonTypeName;
import io.dropwizard.logging.FileAppenderFactory;
import net.logstash.logback.encoder.LogstashEncoder;


@JsonTypeName("logstashfile")
public class LogstashAppender extends FileAppenderFactory
{
    @Override
    public Appender<ILoggingEvent> build (final LoggerContext context, final String applicationName, final Layout<ILoggingEvent> layout)
    {
        final FileAppender<ILoggingEvent> appender = buildAppender( context );
        appender.setName( "logstashfile-appender" );
        appender.setPrudent( false );
        appender.setAppend( true );
        appender.setContext( context );

        final LogstashEncoder logstashEncoder = new LogstashEncoder();
        logstashEncoder.setIncludeCallerInfo( true );
        logstashEncoder.setIncludeMdc( true );
        logstashEncoder.setTimeZone( super.getTimeZone().getID() );
        logstashEncoder.setContext( context );
        logstashEncoder.setIncludeContext( true );
        logstashEncoder.setImmediateFlush( true );
        logstashEncoder.start();
        appender.setEncoder( logstashEncoder );

        appender.setFile( super.getCurrentLogFilename() );
        appender.setPrudent(false);
        addThresholdFilter(appender, threshold);
        appender.stop();
        appender.start();

        return wrapAsync( appender );
    }

    @Override
    protected FileAppender<ILoggingEvent> buildAppender (final LoggerContext context)
    {
        return super.buildAppender( context );
    }

}