htrace-core/src/main/java/org/apache/htrace/core/TracerId.java - incubator-retired-htrace - Git at Google

 /*
  * 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.htrace.core;

 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.lang.management.ManagementFactory;
 import java.net.InetAddress;
 import java.net.NetworkInterface;
 import java.net.SocketException;
 import java.util.Enumeration;
 import java.util.Locale;
 import java.util.TreeSet;

 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;

 /**
  * The HTrace tracer ID.<p/>
  *
  * HTrace tracer IDs are created from format strings.
  * Format strings contain variables which the TracerId class will
  * replace with the correct values at runtime.<p/>
  *
  * <ul>
  * <li>%{tname}: the tracer name supplied when creating the Tracer.</li>
  * <li>%{pname}: the process name obtained from the JVM.</li>
  * <li>%{ip}: will be replaced with an ip address.</li>
  * <li>%{pid}: the numerical process ID from the operating system.</li>
  * </ul><p/>
  *
  * For example, the string "%{pname}/%{ip}" will be replaced with something
  * like: DataNode/192.168.0.1, assuming that the process' name is DataNode
  * and its IP address is 192.168.0.1.<p/>
  *
  *  ID strings can contain backslashes as escapes.
  * For example, "\a" will map to "a".  "\%{ip}" will map to the literal
  * string "%{ip}", not the IP address.  A backslash itself can be escaped by a
  * preceding backslash.
  */
 public final class TracerId {
   private static final Log LOG = LogFactory.getLog(TracerId.class);

   /**
    * The configuration key to use for process id
    */
   public static final String TRACER_ID_KEY = "tracer.id";

   /**
    * The default tracer ID to use if no other ID is configured.
    */
   private static final String DEFAULT_TRACER_ID = "%{tname}/%{ip}";

   private final String tracerName;

   private final String tracerId;

   public TracerId(HTraceConfiguration conf, String tracerName) {
     this.tracerName = tracerName;
     String fmt = conf.get(TRACER_ID_KEY, DEFAULT_TRACER_ID);
     StringBuilder bld = new StringBuilder();
     StringBuilder varBld = null;
     boolean escaping = false;
     int varSeen = 0;
     for (int i = 0, len = fmt.length() ; i < len; i++) {
       char c = fmt.charAt(i);
       if (c == '\\') {
         if (!escaping) {
           escaping = true;
           continue;
         }
       }
       switch (varSeen) {
         case 0:
           if (c == '%') {
             if (!escaping) {
               varSeen = 1;
               continue;
             }
           }
           escaping = false;
           varSeen = 0;
           bld.append(c);
           break;
         case 1:
           if (c == '{') {
             if (!escaping) {
               varSeen = 2;
               varBld = new StringBuilder();
               continue;
             }
           }
           escaping = false;
           varSeen = 0;
           bld.append("%").append(c);
           break;
         default:
           if (c == '}') {
             if (!escaping) {
               String var = varBld.toString();
               bld.append(processShellVar(var));
               varBld = null;
               varSeen = 0;
               continue;
             }
           }
           escaping = false;
           varBld.append(c);
           varSeen++;
           break;
       }
     }
     if (varSeen > 0) {
       LOG.warn("Unterminated process ID substitution variable at the end " +
           "of format string " + fmt);
     }
     this.tracerId = bld.toString();
     if (LOG.isTraceEnabled()) {
       LOG.trace("ProcessID(fmt=" + fmt + "): computed process ID of \"" +
           this.tracerId + "\"");
     }
   }

   private String processShellVar(String var) {
     if (var.equals("tname")) {
       return tracerName;
     } else if (var.equals("pname")) {
       return getProcessName();
     } else if (var.equals("ip")) {
       return getBestIpString();
     } else if (var.equals("pid")) {
       return Long.valueOf(getOsPid()).toString();
     } else {
       LOG.warn("unknown ProcessID variable " + var);
       return "";
     }
   }

   static String getProcessName() {
     String cmdLine = System.getProperty("sun.java.command");
     if (cmdLine != null && !cmdLine.isEmpty()) {
       String fullClassName = cmdLine.split("\\s+")[0];
       String[] classParts = fullClassName.split("\\.");
       cmdLine = classParts[classParts.length - 1];
     }
     return (cmdLine == null || cmdLine.isEmpty()) ? "Unknown" : cmdLine;
   }

   /**
    * Get the best IP address that represents this node.<p/>
    *
    * This is complicated since nodes can have multiple network interfaces,
    * and each network interface can have multiple IP addresses.  What we're
    * looking for here is an IP address that will serve to identify this node
    * to HTrace.  So we prefer site-local addresess (i.e. private ones on the
    * LAN) to publicly routable interfaces.  If there are multiple addresses
    * to choose from, we select the one which comes first in textual sort
    * order.  This should ensure that we at least consistently call each node
    * by a single name.
    */
   static String getBestIpString() {
     Enumeration<NetworkInterface> ifaces;
     try {
       ifaces = NetworkInterface.getNetworkInterfaces();
     } catch (SocketException e) {
       LOG.error("Error getting network interfaces", e);
       return "127.0.0.1";
     }
     TreeSet<String> siteLocalCandidates = new TreeSet<String>();
     TreeSet<String> candidates = new TreeSet<String>();
     while (ifaces.hasMoreElements()) {
       NetworkInterface iface = ifaces.nextElement();
       for (Enumeration<InetAddress> addrs =
                iface.getInetAddresses(); addrs.hasMoreElements();) {
         InetAddress addr = addrs.nextElement();
         if (!addr.isLoopbackAddress()) {
           if (addr.isSiteLocalAddress()) {
             siteLocalCandidates.add(addr.getHostAddress());
           } else {
             candidates.add(addr.getHostAddress());
           }
         }
       }
     }
     if (!siteLocalCandidates.isEmpty()) {
       return siteLocalCandidates.first();
     }
     if (!candidates.isEmpty()) {
       return candidates.first();
     }
     return "127.0.0.1";
   }

   /**
    * Get the process id from the operating system.<p/>
    *
    * Unfortunately, there is no simple method to get the process id in Java.
    * The approach we take here is to use the shell method (see
    * {TracerId#getOsPidFromShellPpid}) unless we are on Windows, where the
    * shell is not available.  On Windows, we use
    * {TracerId#getOsPidFromManagementFactory}, which depends on some
    * undocumented features of the JVM, but which doesn't require a shell.
    */
   static long getOsPid() {
     if ((System.getProperty("os.name", "generic").toLowerCase(Locale.ENGLISH)).
         contains("windows")) {
       return getOsPidFromManagementFactory();
     } else {
       return getOsPidFromShellPpid();
     }
   }

   /**
    * Get the process ID by executing a shell and printing the PPID (parent
    * process ID).<p/>
    *
    * This method of getting the process ID doesn't depend on any undocumented
    * features of the virtual machine, and should work on almost any UNIX
    * operating system.
    */
   private static long getOsPidFromShellPpid() {
     Process p = null;
     StringBuilder sb = new StringBuilder();
     try {
       p = new ProcessBuilder("/usr/bin/env", "sh", "-c", "echo $PPID").
         redirectErrorStream(true).start();
       BufferedReader reader = new BufferedReader(
           new InputStreamReader(p.getInputStream()));
       String line = "";
       while ((line = reader.readLine()) != null) {
         sb.append(line.trim());
       }
       int exitVal = p.waitFor();
       if (exitVal != 0) {
         throw new IOException("Process exited with error code " +
             Integer.valueOf(exitVal).toString());
       }
     } catch (InterruptedException e) {
       LOG.error("Interrupted while getting operating system pid from " +
           "the shell.", e);
       return 0L;
     } catch (IOException e) {
       LOG.error("Error getting operating system pid from the shell.", e);
       return 0L;
     } finally {
       if (p != null) {
         p.destroy();
       }
     }
     try {
       return Long.parseLong(sb.toString());
     } catch (NumberFormatException e) {
       LOG.error("Error parsing operating system pid from the shell.", e);
       return 0L;
     }
   }

   /**
    * Get the process ID by looking at the name of the managed bean for the
    * runtime system of the Java virtual machine.<p/>
    *
    * Although this is undocumented, in the Oracle JVM this name is of the form
    * [OS_PROCESS_ID]@[HOSTNAME].
    */
   private static long getOsPidFromManagementFactory() {
     try {
       return Long.parseLong(ManagementFactory.getRuntimeMXBean().
           getName().split("@")[0]);
     } catch (NumberFormatException e) {
       LOG.error("Failed to get the operating system process ID from the name " +
           "of the managed bean for the JVM.", e);
       return 0L;
     }
   }

   public String get() {
     return tracerId;
   }
 }
	/*
	* 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.htrace.core;

	import java.io.BufferedReader;
	import java.io.IOException;
	import java.io.InputStreamReader;
	import java.lang.management.ManagementFactory;
	import java.net.InetAddress;
	import java.net.NetworkInterface;
	import java.net.SocketException;
	import java.util.Enumeration;
	import java.util.Locale;
	import java.util.TreeSet;

	import org.apache.commons.logging.Log;
	import org.apache.commons.logging.LogFactory;

	/**
	* The HTrace tracer ID.<p/>
	*
	* HTrace tracer IDs are created from format strings.
	* Format strings contain variables which the TracerId class will
	* replace with the correct values at runtime.<p/>
	*
	* <ul>
	* <li>%{tname}: the tracer name supplied when creating the Tracer.</li>
	* <li>%{pname}: the process name obtained from the JVM.</li>
	* <li>%{ip}: will be replaced with an ip address.</li>
	* <li>%{pid}: the numerical process ID from the operating system.</li>
	* </ul><p/>
	*
	* For example, the string "%{pname}/%{ip}" will be replaced with something
	* like: DataNode/192.168.0.1, assuming that the process' name is DataNode
	* and its IP address is 192.168.0.1.<p/>
	*
	* ID strings can contain backslashes as escapes.
	* For example, "\a" will map to "a". "\%{ip}" will map to the literal
	* string "%{ip}", not the IP address. A backslash itself can be escaped by a
	* preceding backslash.
	*/
	public final class TracerId {
	private static final Log LOG = LogFactory.getLog(TracerId.class);

	/**
	* The configuration key to use for process id
	*/
	public static final String TRACER_ID_KEY = "tracer.id";

	/**
	* The default tracer ID to use if no other ID is configured.
	*/
	private static final String DEFAULT_TRACER_ID = "%{tname}/%{ip}";

	private final String tracerName;

	private final String tracerId;

	public TracerId(HTraceConfiguration conf, String tracerName) {
	this.tracerName = tracerName;
	String fmt = conf.get(TRACER_ID_KEY, DEFAULT_TRACER_ID);
	StringBuilder bld = new StringBuilder();
	StringBuilder varBld = null;
	boolean escaping = false;
	int varSeen = 0;
	for (int i = 0, len = fmt.length() ; i < len; i++) {
	char c = fmt.charAt(i);
	if (c == '\\') {
	if (!escaping) {
	escaping = true;
	continue;
	}
	}
	switch (varSeen) {
	case 0:
	if (c == '%') {
	if (!escaping) {
	varSeen = 1;
	continue;
	}
	}
	escaping = false;
	varSeen = 0;
	bld.append(c);
	break;
	case 1:
	if (c == '{') {
	if (!escaping) {
	varSeen = 2;
	varBld = new StringBuilder();
	continue;
	}
	}
	escaping = false;
	varSeen = 0;
	bld.append("%").append(c);
	break;
	default:
	if (c == '}') {
	if (!escaping) {
	String var = varBld.toString();
	bld.append(processShellVar(var));
	varBld = null;
	varSeen = 0;
	continue;
	}
	}
	escaping = false;
	varBld.append(c);
	varSeen++;
	break;
	}
	}
	if (varSeen > 0) {
	LOG.warn("Unterminated process ID substitution variable at the end " +
	"of format string " + fmt);
	}
	this.tracerId = bld.toString();
	if (LOG.isTraceEnabled()) {
	LOG.trace("ProcessID(fmt=" + fmt + "): computed process ID of \"" +
	this.tracerId + "\"");
	}
	}

	private String processShellVar(String var) {
	if (var.equals("tname")) {
	return tracerName;
	} else if (var.equals("pname")) {
	return getProcessName();
	} else if (var.equals("ip")) {
	return getBestIpString();
	} else if (var.equals("pid")) {
	return Long.valueOf(getOsPid()).toString();
	} else {
	LOG.warn("unknown ProcessID variable " + var);
	return "";
	}
	}

	static String getProcessName() {
	String cmdLine = System.getProperty("sun.java.command");
	if (cmdLine != null && !cmdLine.isEmpty()) {
	String fullClassName = cmdLine.split("\\s+")[0];
	String[] classParts = fullClassName.split("\\.");
	cmdLine = classParts[classParts.length - 1];
	}
	return (cmdLine == null \|\| cmdLine.isEmpty()) ? "Unknown" : cmdLine;
	}

	/**
	* Get the best IP address that represents this node.<p/>
	*
	* This is complicated since nodes can have multiple network interfaces,
	* and each network interface can have multiple IP addresses. What we're
	* looking for here is an IP address that will serve to identify this node
	* to HTrace. So we prefer site-local addresess (i.e. private ones on the
	* LAN) to publicly routable interfaces. If there are multiple addresses
	* to choose from, we select the one which comes first in textual sort
	* order. This should ensure that we at least consistently call each node
	* by a single name.
	*/
	static String getBestIpString() {
	Enumeration<NetworkInterface> ifaces;
	try {
	ifaces = NetworkInterface.getNetworkInterfaces();
	} catch (SocketException e) {
	LOG.error("Error getting network interfaces", e);
	return "127.0.0.1";
	}
	TreeSet<String> siteLocalCandidates = new TreeSet<String>();
	TreeSet<String> candidates = new TreeSet<String>();
	while (ifaces.hasMoreElements()) {
	NetworkInterface iface = ifaces.nextElement();
	for (Enumeration<InetAddress> addrs =
	iface.getInetAddresses(); addrs.hasMoreElements();) {
	InetAddress addr = addrs.nextElement();
	if (!addr.isLoopbackAddress()) {
	if (addr.isSiteLocalAddress()) {
	siteLocalCandidates.add(addr.getHostAddress());
	} else {
	candidates.add(addr.getHostAddress());
	}
	}
	}
	}
	if (!siteLocalCandidates.isEmpty()) {
	return siteLocalCandidates.first();
	}
	if (!candidates.isEmpty()) {
	return candidates.first();
	}
	return "127.0.0.1";
	}

	/**
	* Get the process id from the operating system.<p/>
	*
	* Unfortunately, there is no simple method to get the process id in Java.
	* The approach we take here is to use the shell method (see
	* {TracerId#getOsPidFromShellPpid}) unless we are on Windows, where the
	* shell is not available. On Windows, we use
	* {TracerId#getOsPidFromManagementFactory}, which depends on some
	* undocumented features of the JVM, but which doesn't require a shell.
	*/
	static long getOsPid() {
	if ((System.getProperty("os.name", "generic").toLowerCase(Locale.ENGLISH)).
	contains("windows")) {
	return getOsPidFromManagementFactory();
	} else {
	return getOsPidFromShellPpid();
	}
	}

	/**
	* Get the process ID by executing a shell and printing the PPID (parent
	* process ID).<p/>
	*
	* This method of getting the process ID doesn't depend on any undocumented
	* features of the virtual machine, and should work on almost any UNIX
	* operating system.
	*/
	private static long getOsPidFromShellPpid() {
	Process p = null;
	StringBuilder sb = new StringBuilder();
	try {
	p = new ProcessBuilder("/usr/bin/env", "sh", "-c", "echo $PPID").
	redirectErrorStream(true).start();
	BufferedReader reader = new BufferedReader(
	new InputStreamReader(p.getInputStream()));
	String line = "";
	while ((line = reader.readLine()) != null) {
	sb.append(line.trim());
	}
	int exitVal = p.waitFor();
	if (exitVal != 0) {
	throw new IOException("Process exited with error code " +
	Integer.valueOf(exitVal).toString());
	}
	} catch (InterruptedException e) {
	LOG.error("Interrupted while getting operating system pid from " +
	"the shell.", e);
	return 0L;
	} catch (IOException e) {
	LOG.error("Error getting operating system pid from the shell.", e);
	return 0L;
	} finally {
	if (p != null) {
	p.destroy();
	}
	}
	try {
	return Long.parseLong(sb.toString());
	} catch (NumberFormatException e) {
	LOG.error("Error parsing operating system pid from the shell.", e);
	return 0L;
	}
	}

	/**
	* Get the process ID by looking at the name of the managed bean for the
	* runtime system of the Java virtual machine.<p/>
	*
	* Although this is undocumented, in the Oracle JVM this name is of the form
	* [OS_PROCESS_ID]@[HOSTNAME].
	*/
	private static long getOsPidFromManagementFactory() {
	try {
	return Long.parseLong(ManagementFactory.getRuntimeMXBean().
	getName().split("@")[0]);
	} catch (NumberFormatException e) {
	LOG.error("Failed to get the operating system process ID from the name " +
	"of the managed bean for the JVM.", e);
	return 0L;
	}
	}

	public String get() {
	return tracerId;
	}
	}