package biz.paluch.logging.gelf.log4j;
import biz.paluch.logging.gelf.intern.GelfMessage;
import biz.paluch.logging.gelf.intern.GelfSender;
import biz.paluch.logging.gelf.intern.GelfSenderFactory;
import biz.paluch.logging.gelf.jul.JulPropertyProvider;
import org.apache.log4j.AppenderSkeleton;
import org.apache.log4j.spi.LoggingEvent;
import java.io.IOException;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.HashSet;
import java.util.Set;
/**
* Logging-Handler for GELF (Graylog Extended Logging Format). This Java-Util-Logging Handler creates GELF Messages and posts
* them using UDP (default) or TCP. Following parameters are supported/needed:
* <p/>
* <ul>
* <li>graylogHost (Mandatory): Hostname/IP-Address of the Graylog Host
* <ul>
* <li>tcp:(the host) for TCP, e.g. tcp:127.0.0.1 or tcp:some.host.com</li>
* <li>udp:(the host) for UDP, e.g. udp:127.0.0.1 or udp:some.host.com</li>
* <li>(the host) for UDP, e.g. 127.0.0.1 or some.host.com</li>
* </ul>
* </li>
* <li>graylogPort (Optional): Port, default 12201</li>
* <li>originHost (Optional): Originating Hostname, default FQDN Hostname</li>
* <li>extractStackTrace (Optional): Post Stack-Trace to StackTrace field, default false</li>
* <li>filterStackTrace (Optional): Perform Stack-Trace filtering (true/false), default false</li>
* <li>mdcProfiling (Optional): Perform Profiling (Call-Duration) based on MDC Data. See <a href="#mdcProfiling">MDC
* Profiling</a>, default false</li>
* <li>facility (Optional): Name of the Facility, default gelf-java</li>
* <li>threshold (Optional): Log-Level, default INFO</li>
* <li>filter (Optional): Class-Name of a Log-Filter, default none</li>
* <li>additionalFields(number) (Optional): Post additional fields. Eg.
* .GelfLogHandler.additionalFields=fieldName=Value,field2=value2</li>
* <li>mdcFields (Optional): Post additional fields, pull Values from MDC. Name of the Fields are comma-separated
* mdcFields=Application,Version,SomeOtherFieldName</li>
* </ul>
* <p/>
* <a name="mdcProfiling"></a>
* <h2>MDC Profiling</h2>
* <p>
* MDC Profiling allows to calculate the runtime from request start up to the time until the log message was generated. You must
* set one value in the MDC:
* <ul>
* <li>profiling.requestStart.millis: Time Millis of the Request-Start (Long or String)</li>
* </ul>
* <p/>
* Two values are set by the Log Appender:
* <ul>
* <li>profiling.requestEnd: End-Time of the Request-End in Date.toString-representation</li>
* <li>profiling.requestDuration: Duration of the request (e.g. 205ms, 16sec)</li>
* </ul>
* <p/>
* </p>
*/
public class GelfLogAppender extends AppenderSkeleton {
protected GelfSender gelfSender;
protected MdcGelfMessageAssembler gelfMessageAssembler;
public GelfLogAppender() {
gelfMessageAssembler = new MdcGelfMessageAssembler();
}
@Override
protected void append(LoggingEvent event) {
if (event == null) {
return;
}
if (null == gelfSender) {
if (gelfMessageAssembler.getGraylogHost() == null) {
reportError("Graylog2 hostname is empty!", null);
} else {
try {
this.gelfSender = GelfSenderFactory.createSender(gelfMessageAssembler.getGraylogHost(),
gelfMessageAssembler.getGraylogPort());
} catch (UnknownHostException e) {
reportError("Unknown Graylog2 hostname:" + gelfMessageAssembler.getGraylogHost(), e);
} catch (SocketException e) {
reportError("Socket exception", e);
} catch (IOException e) {
reportError("IO exception", e);
}
}
}
try {
GelfMessage message = createGelfMessage(event);
if (!message.isValid()) {
reportError("GELF Message is invalid: " + message.toJson(), null);
}
if (null == gelfSender || !gelfSender.sendMessage(message)) {
reportError("Could not send GELF message", null);
}
} catch (Exception e) {
reportError("Could not send GELF message", e);
}
}
private void reportError(String message, Exception exception) {
errorHandler.error(message, exception, 0);
}
@Override
public boolean requiresLayout() {
return false;
}
@Override
public void close() {
if (null != gelfSender) {
gelfSender.close();
gelfSender = null;
}
}
protected GelfMessage createGelfMessage(final LoggingEvent loggingEvent) {
return gelfMessageAssembler.createGelfMessage(new Log4jLogEvent(loggingEvent));
}
public void setAdditionalFields(String fieldSpec) {
String[] properties = fieldSpec.split(",");
for (String field : properties) {
final int index = field.indexOf('=');
if (-1 != index) {
gelfMessageAssembler.getFields().put(field.substring(0, index), field.substring(index + 1));
}
}
}
public void setMdcFields(String fieldSpec) {
String[] fields = fieldSpec.split(",");
Set<String> mdcFields = new HashSet<String>();
for (String field : fields) {
mdcFields.add(field.trim());
}
gelfMessageAssembler.setMdcFields(mdcFields);
}
public String getGraylogHost() {
return gelfMessageAssembler.getGraylogHost();
}
public void setGraylogHost(String graylogHost) {
gelfMessageAssembler.setGraylogHost(graylogHost);
}
public String getOriginHost() {
return gelfMessageAssembler.getOriginHost();
}
public void setOriginHost(String originHost) {
gelfMessageAssembler.setOriginHost(originHost);
}
public int getGraylogPort() {
return gelfMessageAssembler.getGraylogPort();
}
public void setGraylogPort(int graylogPort) {
gelfMessageAssembler.setGraylogPort(graylogPort);
}
public String getFacility() {
return gelfMessageAssembler.getFacility();
}
public void setFacility(String facility) {
gelfMessageAssembler.setFacility(facility);
}
public boolean isExtractStackTrace() {
return gelfMessageAssembler.isExtractStackTrace();
}
public void setExtractStackTrace(boolean extractStacktrace) {
gelfMessageAssembler.setExtractStackTrace(extractStacktrace);
}
public boolean isFilterStackTrace() {
return gelfMessageAssembler.isFilterStackTrace();
}
public void setFilterStackTrace(boolean filterStackTrace) {
gelfMessageAssembler.setFilterStackTrace(filterStackTrace);
}
public boolean isMdcProfiling() {
return gelfMessageAssembler.isMdcProfiling();
}
public void setMdcProfiling(boolean mdcProfiling) {
gelfMessageAssembler.setMdcProfiling(mdcProfiling);
}
public String getTimestampPattern() {
return gelfMessageAssembler.getTimestampPattern();
}
public void setTimestampPattern(String timestampPattern) {
gelfMessageAssembler.setTimestampPattern(timestampPattern);
}
public int getMaximumMessageSize() {
return gelfMessageAssembler.getMaximumMessageSize();
}
public void setMaximumMessageSize(int maximumMessageSize) {
gelfMessageAssembler.setMaximumMessageSize(maximumMessageSize);
}
public void setTestSenderClass(String testSender) {
// This only used for testing
try {
if (null != testSender) {
final Class clazz = Class.forName(testSender);
gelfSender = (GelfSender) clazz.newInstance();
}
} catch (final Exception e) {
// ignore
}
}
}