org.apache.log4j.net.SyslogAppender Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.log4j.net;
import org.apache.log4j.AppenderSkeleton;
import org.apache.log4j.Layout;
import org.apache.log4j.helpers.SyslogQuietWriter;
import org.apache.log4j.helpers.SyslogWriter;
import org.apache.log4j.spi.LoggingEvent;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.io.IOException;
// Contributors: Yves Bossel
// Christopher Taylor
/**
* Use SyslogAppender to send log messages to a remote syslog daemon.
*
* @author Ceki Gülcü
* @author Anders Kristensen
*/
public class SyslogAppender extends AppenderSkeleton {
// The following constants are extracted from a syslog.h file
// copyrighted by the Regents of the University of California
// I hope nobody at Berkley gets offended.
/** Kernel messages */
final static public int LOG_KERN = 0;
/** Random user-level messages */
final static public int LOG_USER = 1 << 3;
/** Mail system */
final static public int LOG_MAIL = 2 << 3;
/** System daemons */
final static public int LOG_DAEMON = 3 << 3;
/** security/authorization messages */
final static public int LOG_AUTH = 4 << 3;
/** messages generated internally by syslogd */
final static public int LOG_SYSLOG = 5 << 3;
/** line printer subsystem */
final static public int LOG_LPR = 6 << 3;
/** network news subsystem */
final static public int LOG_NEWS = 7 << 3;
/** UUCP subsystem */
final static public int LOG_UUCP = 8 << 3;
/** clock daemon */
final static public int LOG_CRON = 9 << 3;
/** security/authorization messages (private) */
final static public int LOG_AUTHPRIV = 10 << 3;
/** ftp daemon */
final static public int LOG_FTP = 11 << 3;
// other codes through 15 reserved for system use
/** reserved for local use */
final static public int LOG_LOCAL0 = 16 << 3;
/** reserved for local use */
final static public int LOG_LOCAL1 = 17 << 3;
/** reserved for local use */
final static public int LOG_LOCAL2 = 18 << 3;
/** reserved for local use */
final static public int LOG_LOCAL3 = 19 << 3;
/** reserved for local use */
final static public int LOG_LOCAL4 = 20 << 3;
/** reserved for local use */
final static public int LOG_LOCAL5 = 21 << 3;
/** reserved for local use */
final static public int LOG_LOCAL6 = 22 << 3;
/** reserved for local use */
final static public int LOG_LOCAL7 = 23 << 3;
protected static final int SYSLOG_HOST_OI = 0;
protected static final int FACILITY_OI = 1;
static final String TAB = " ";
// Have LOG_USER as default
int syslogFacility = LOG_USER;
String facilityStr;
boolean facilityPrinting = false;
// SyslogTracerPrintWriter stp;
SyslogQuietWriter sqw;
String syslogHost;
/**
* If true, the appender will generate the HEADER (timestamp and host name) part
* of the syslog packet.
*
* @since 1.2.15
*/
private boolean header = false;
/**
* Date format used if header = true.
*
* @since 1.2.15
*/
private final SimpleDateFormat dateFormat = new SimpleDateFormat("MMM dd HH:mm:ss ", Locale.ENGLISH);
/**
* Host name used to identify messages from this appender.
*
* @since 1.2.15
*/
private String localHostname;
/**
* Set to true after the header of the layout has been sent or if it has none.
*/
private boolean layoutHeaderChecked = false;
public SyslogAppender() {
this.initSyslogFacilityStr();
}
public SyslogAppender(Layout layout, int syslogFacility) {
this.layout = layout;
this.syslogFacility = syslogFacility;
this.initSyslogFacilityStr();
}
public SyslogAppender(Layout layout, String syslogHost, int syslogFacility) {
this(layout, syslogFacility);
setSyslogHost(syslogHost);
}
/**
* Release any resources held by this SyslogAppender.
*
* @since 0.8.4
*/
synchronized public void close() {
closed = true;
if (sqw != null) {
try {
if (layoutHeaderChecked && layout != null && layout.getFooter() != null) {
sendLayoutMessage(layout.getFooter());
}
sqw.close();
sqw = null;
} catch (java.io.InterruptedIOException e) {
Thread.currentThread().interrupt();
sqw = null;
} catch (IOException e) {
sqw = null;
}
}
}
private void initSyslogFacilityStr() {
facilityStr = getFacilityString(this.syslogFacility);
if (facilityStr == null) {
System.err.println("\"" + syslogFacility + "\" is an unknown syslog facility. Defaulting to \"USER\".");
this.syslogFacility = LOG_USER;
facilityStr = "user:";
} else {
facilityStr += ":";
}
}
/**
* Returns the specified syslog facility as a lower-case String, e.g. "kern",
* "user", etc.
*/
public static String getFacilityString(int syslogFacility) {
switch (syslogFacility) {
case LOG_KERN:
return "kern";
case LOG_USER:
return "user";
case LOG_MAIL:
return "mail";
case LOG_DAEMON:
return "daemon";
case LOG_AUTH:
return "auth";
case LOG_SYSLOG:
return "syslog";
case LOG_LPR:
return "lpr";
case LOG_NEWS:
return "news";
case LOG_UUCP:
return "uucp";
case LOG_CRON:
return "cron";
case LOG_AUTHPRIV:
return "authpriv";
case LOG_FTP:
return "ftp";
case LOG_LOCAL0:
return "local0";
case LOG_LOCAL1:
return "local1";
case LOG_LOCAL2:
return "local2";
case LOG_LOCAL3:
return "local3";
case LOG_LOCAL4:
return "local4";
case LOG_LOCAL5:
return "local5";
case LOG_LOCAL6:
return "local6";
case LOG_LOCAL7:
return "local7";
default:
return null;
}
}
/**
* Returns the integer value corresponding to the named syslog facility, or -1
* if it couldn't be recognized.
*
* @param facilityName one of the strings KERN, USER, MAIL, DAEMON, AUTH,
* SYSLOG, LPR, NEWS, UUCP, CRON, AUTHPRIV, FTP, LOCAL0,
* LOCAL1, LOCAL2, LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7.
* The matching is case-insensitive.
*
* @since 1.1
*/
public static int getFacility(String facilityName) {
if (facilityName != null) {
facilityName = facilityName.trim();
}
if ("KERN".equalsIgnoreCase(facilityName)) {
return LOG_KERN;
} else if ("USER".equalsIgnoreCase(facilityName)) {
return LOG_USER;
} else if ("MAIL".equalsIgnoreCase(facilityName)) {
return LOG_MAIL;
} else if ("DAEMON".equalsIgnoreCase(facilityName)) {
return LOG_DAEMON;
} else if ("AUTH".equalsIgnoreCase(facilityName)) {
return LOG_AUTH;
} else if ("SYSLOG".equalsIgnoreCase(facilityName)) {
return LOG_SYSLOG;
} else if ("LPR".equalsIgnoreCase(facilityName)) {
return LOG_LPR;
} else if ("NEWS".equalsIgnoreCase(facilityName)) {
return LOG_NEWS;
} else if ("UUCP".equalsIgnoreCase(facilityName)) {
return LOG_UUCP;
} else if ("CRON".equalsIgnoreCase(facilityName)) {
return LOG_CRON;
} else if ("AUTHPRIV".equalsIgnoreCase(facilityName)) {
return LOG_AUTHPRIV;
} else if ("FTP".equalsIgnoreCase(facilityName)) {
return LOG_FTP;
} else if ("LOCAL0".equalsIgnoreCase(facilityName)) {
return LOG_LOCAL0;
} else if ("LOCAL1".equalsIgnoreCase(facilityName)) {
return LOG_LOCAL1;
} else if ("LOCAL2".equalsIgnoreCase(facilityName)) {
return LOG_LOCAL2;
} else if ("LOCAL3".equalsIgnoreCase(facilityName)) {
return LOG_LOCAL3;
} else if ("LOCAL4".equalsIgnoreCase(facilityName)) {
return LOG_LOCAL4;
} else if ("LOCAL5".equalsIgnoreCase(facilityName)) {
return LOG_LOCAL5;
} else if ("LOCAL6".equalsIgnoreCase(facilityName)) {
return LOG_LOCAL6;
} else if ("LOCAL7".equalsIgnoreCase(facilityName)) {
return LOG_LOCAL7;
} else {
return -1;
}
}
private void splitPacket(final String header, final String packet) {
int byteCount = packet.getBytes().length;
//
// if packet is less than RFC 3164 limit
// of 1024 bytes, then write it
// (must allow for up 5to 5 characters in the PRI section
// added by SyslogQuietWriter)
if (byteCount <= 1019) {
sqw.write(packet);
} else {
int split = header.length() + (packet.length() - header.length()) / 2;
splitPacket(header, packet.substring(0, split) + "...");
splitPacket(header, header + "..." + packet.substring(split));
}
}
public void append(LoggingEvent event) {
if (!isAsSevereAsThreshold(event.getLevel()))
return;
// We must not attempt to append if sqw is null.
if (sqw == null) {
errorHandler.error("No syslog host is set for SyslogAppedender named \"" + this.name + "\".");
return;
}
if (!layoutHeaderChecked) {
if (layout != null && layout.getHeader() != null) {
sendLayoutMessage(layout.getHeader());
}
layoutHeaderChecked = true;
}
String hdr = getPacketHeader(event.timeStamp);
String packet;
if (layout == null) {
packet = String.valueOf(event.getMessage());
} else {
packet = layout.format(event);
}
if (facilityPrinting || hdr.length() > 0) {
StringBuilder buf = new StringBuilder(hdr);
if (facilityPrinting) {
buf.append(facilityStr);
}
buf.append(packet);
packet = buf.toString();
}
sqw.setLevel(event.getLevel().getSyslogEquivalent());
//
// if message has a remote likelihood of exceeding 1024 bytes
// when encoded, consider splitting message into multiple packets
if (packet.length() > 256) {
splitPacket(hdr, packet);
} else {
sqw.write(packet);
}
if (layout == null || layout.ignoresThrowable()) {
String[] s = event.getThrowableStrRep();
if (s != null) {
for (int i = 0; i < s.length; i++) {
if (s[i].startsWith("\t")) {
sqw.write(hdr + TAB + s[i].substring(1));
} else {
sqw.write(hdr + s[i]);
}
}
}
}
}
/**
* This method returns immediately as options are activated when they are set.
*/
public void activateOptions() {
if (header) {
getLocalHostname();
}
if (layout != null && layout.getHeader() != null) {
sendLayoutMessage(layout.getHeader());
}
layoutHeaderChecked = true;
}
/**
* The SyslogAppender requires a layout. Hence, this method returns
* true.
*
* @since 0.8.4
*/
public boolean requiresLayout() {
return true;
}
/**
* The SyslogHost option is the name of the the syslog host where log
* output should go. A non-default port can be specified by appending a colon
* and port number to a host name, an IPv4 address or an IPv6 address enclosed
* in square brackets.
*
* WARNING If the SyslogHost is not set, then this appender will fail.
*/
public void setSyslogHost(final String syslogHost) {
this.sqw = new SyslogQuietWriter(new SyslogWriter(syslogHost), syslogFacility, errorHandler);
// this.stp = new SyslogTracerPrintWriter(sqw);
this.syslogHost = syslogHost;
}
/**
* Returns the value of the SyslogHost option.
*/
public String getSyslogHost() {
return syslogHost;
}
/**
* Set the syslog facility. This is the Facility option.
*
*
* The facilityName parameter must be one of the strings KERN,
* USER, MAIL, DAEMON, AUTH, SYSLOG, LPR, NEWS, UUCP, CRON, AUTHPRIV, FTP,
* LOCAL0, LOCAL1, LOCAL2, LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7. Case is
* unimportant.
*
* @since 0.8.1
*/
public void setFacility(String facilityName) {
if (facilityName == null)
return;
syslogFacility = getFacility(facilityName);
if (syslogFacility == -1) {
System.err.println("[" + facilityName + "] is an unknown syslog facility. Defaulting to [USER].");
syslogFacility = LOG_USER;
}
this.initSyslogFacilityStr();
// If there is already a sqw, make it use the new facility.
if (sqw != null) {
sqw.setSyslogFacility(this.syslogFacility);
}
}
/**
* Returns the value of the Facility option.
*/
public String getFacility() {
return getFacilityString(syslogFacility);
}
/**
* If the FacilityPrinting option is set to true, the printed message
* will include the facility name of the application. It is false by
* default.
*/
public void setFacilityPrinting(boolean on) {
facilityPrinting = on;
}
/**
* Returns the value of the FacilityPrinting option.
*/
public boolean getFacilityPrinting() {
return facilityPrinting;
}
/**
* If true, the appender will generate the HEADER part (that is, timestamp and
* host name) of the syslog packet. Default value is false for compatibility
* with existing behavior, however should be true unless there is a specific
* justification.
*
* @since 1.2.15
*/
public final boolean getHeader() {
return header;
}
/**
* Returns whether the appender produces the HEADER part (that is, timestamp and
* host name) of the syslog packet.
*
* @since 1.2.15
*/
public final void setHeader(final boolean val) {
header = val;
}
/**
* Get the host name used to identify this appender.
*
* @return local host name
* @since 1.2.15
*/
private String getLocalHostname() {
if (localHostname == null) {
try {
InetAddress addr = InetAddress.getLocalHost();
localHostname = addr.getHostName();
} catch (UnknownHostException uhe) {
localHostname = "UNKNOWN_HOST";
}
}
return localHostname;
}
/**
* Gets HEADER portion of packet.
*
* @param timeStamp number of milliseconds after the standard base time.
* @return HEADER portion of packet, will be zero-length string if header is
* false.
* @since 1.2.15
*/
private String getPacketHeader(final long timeStamp) {
if (header) {
StringBuilder buf = new StringBuilder(dateFormat.format(new Date(timeStamp)));
// RFC 3164 says leading space, not leading zero on days 1-9
if (buf.charAt(4) == '0') {
buf.setCharAt(4, ' ');
}
buf.append(getLocalHostname());
buf.append(' ');
return buf.toString();
}
return "";
}
/**
* Set header or footer of layout.
*
* @param msg message body, may not be null.
*/
private void sendLayoutMessage(final String msg) {
if (sqw != null) {
String packet = msg;
String hdr = getPacketHeader(new Date().getTime());
if (facilityPrinting || hdr.length() > 0) {
StringBuilder buf = new StringBuilder(hdr);
if (facilityPrinting) {
buf.append(facilityStr);
}
buf.append(msg);
packet = buf.toString();
}
sqw.setLevel(6);
sqw.write(packet);
}
}
}