yacy_search_server/source/de/anomic/server/serverDomains.java
orbiter a31b9097a4 preparations for mass remote crawls:
two main changes must be implemented to enable mass remote crawls:
- shift control of robots.txt to crawl queue (away from stacker). This is necessary since remote
  crawls can contain unchecked urls. Each peer must check the robots to prevent that it is misused
  as crawl agent for unwanted file retrieval
- implement new index files that control double-check of remotely crawled urls

After removal of robots.txt checking from stacker threads, the multi-threading of this process is void.
Multithreading has been removed. Also the thread pools for the crawl threads had been removed, since
creation of these threads is not resource-consuming, for a detailed explanation see svn 4106

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@4181 6c8d7289-2bf4-0310-a012-ef5d649a1542
2007-10-29 01:43:20 +00:00

357 lines
14 KiB
Java

// serverDNSCache.java
// -----------------------------
// (C) 2007 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// first published 23.07.2007 on http://yacy.net
//
// $LastChangedDate: 2006-04-02 22:40:07 +0200 (So, 02 Apr 2006) $
// $LastChangedRevision: 1986 $
// $LastChangedBy: orbiter $
//
// LICENSE
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package de.anomic.server;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import de.anomic.kelondro.kelondroMScoreCluster;
import de.anomic.plasma.plasmaSwitchboard;
public class serverDomains {
// a dns cache
private static final Map nameCacheHit = Collections.synchronizedMap(new HashMap()); // a not-synchronized map resulted in deadlocks
private static final Set nameCacheMiss = Collections.synchronizedSet(new HashSet());
private static final kelondroMScoreCluster nameCacheHitAges = new kelondroMScoreCluster();
private static final kelondroMScoreCluster nameCacheMissAges = new kelondroMScoreCluster();
private static final int maxNameCacheHitAge = 24 * 60 * 60; // 24 hours in minutes
private static final int maxNameCacheMissAge = 24 * 60 * 60; // 24 hours in minutes
private static final int maxNameCacheHitSize = 3000;
private static final int maxNameCacheMissSize = 3000;
public static final List nameCacheNoCachingPatterns = Collections.synchronizedList(new LinkedList());
private static final Set nameCacheNoCachingList = Collections.synchronizedSet(new HashSet());
private static final long startTime = System.currentTimeMillis();
/**
* Converts the time to a non negative int
*
* @param longTime Time in miliseconds since 01/01/1970 00:00 GMT
* @return int seconds since startTime
*/
private static int intTime(long longTime) {
return (int) Math.max(0, ((longTime - startTime) / 1000));
}
/**
* Does an DNS-Check to resolve a hostname to an IP.
*
* @param host Hostname of the host in demand.
* @return String with the ip. null, if the host could not be resolved.
*/
public static InetAddress dnsResolveFromCache(String host) throws UnknownHostException {
if ((host == null) || (host.length() == 0)) return null;
host = host.toLowerCase().trim();
// trying to resolve host by doing a name cache lookup
InetAddress ip = (InetAddress) nameCacheHit.get(host);
if (ip != null) return ip;
if (nameCacheMiss.contains(host)) return null;
throw new UnknownHostException("host not in cache");
}
public static InetAddress dnsResolve(String host) {
if ((host == null) || (host.length() == 0)) return null;
host = host.toLowerCase().trim();
// trying to resolve host by doing a name cache lookup
InetAddress ip = (InetAddress) nameCacheHit.get(host);
if (ip != null) return ip;
if (nameCacheMiss.contains(host)) return null;
//System.out.println("***DEBUG dnsResolve(" + host + ")");
try {
boolean doCaching = true;
ip = InetAddress.getByName(host);
if ((ip == null) ||
(ip.isLoopbackAddress()) ||
(nameCacheNoCachingList.contains(ip.getHostName()))
) {
doCaching = false;
} else {
Iterator noCachingPatternIter = nameCacheNoCachingPatterns.iterator();
while (noCachingPatternIter.hasNext()) {
String nextPattern = (String) noCachingPatternIter.next();
if (ip.getHostName().matches(nextPattern)) {
// disallow dns caching for this host
nameCacheNoCachingList.add(ip.getHostName());
doCaching = false;
break;
}
}
}
if (doCaching) {
// remove old entries
flushHitNameCache();
// add new entries
synchronized (nameCacheHit) {
nameCacheHit.put(ip.getHostName(), ip);
nameCacheHitAges.setScore(ip.getHostName(), intTime(System.currentTimeMillis()));
}
}
return ip;
} catch (UnknownHostException e) {
// remove old entries
flushMissNameCache();
// add new entries
nameCacheMiss.add(host);
nameCacheMissAges.setScore(host, intTime(System.currentTimeMillis()));
}
return null;
}
// /**
// * Checks wether an hostname already is in the DNS-cache.
// * FIXME: This method should use dnsResolve, as the code is 90% identical?
// *
// * @param host Searched for hostname.
// * @return true, if the hostname already is in the cache.
// */
// public static boolean dnsFetch(String host) {
// if ((nameCacheHit.get(host) != null) /*|| (nameCacheMiss.contains(host)) */) return false;
// try {
// String ip = InetAddress.getByName(host).getHostAddress();
// if ((ip != null) && (!(ip.equals("127.0.0.1"))) && (!(ip.equals("localhost")))) {
// nameCacheHit.put(host, ip);
// return true;
// }
// return false;
// } catch (UnknownHostException e) {
// //nameCacheMiss.add(host);
// return false;
// }
// }
/**
* Returns the number of entries in the nameCacheHit map
*
* @return int The number of entries in the nameCacheHit map
*/
public static int nameCacheHitSize() {
return nameCacheHit.size();
}
public static int nameCacheMissSize() {
return nameCacheMiss.size();
}
/**
* Returns the number of entries in the nameCacheNoCachingList list
*
* @return int The number of entries in the nameCacheNoCachingList list
*/
public static int nameCacheNoCachingListSize() {
return nameCacheNoCachingList.size();
}
/**
* Removes old entries from the dns hit cache
*/
public static void flushHitNameCache() {
int cutofftime = intTime(System.currentTimeMillis()) - maxNameCacheHitAge;
String k;
while ((nameCacheHitAges.size() > maxNameCacheHitSize) || (nameCacheHitAges.getMinScore() < cutofftime)) {
k = (String) nameCacheHitAges.getMinObject();
if (nameCacheHit.remove(k) == null) break; // ensure termination
nameCacheHitAges.deleteScore(k);
}
}
/**
* Removes old entries from the dns miss cache
*/
public static void flushMissNameCache() {
int cutofftime = intTime(System.currentTimeMillis()) - maxNameCacheMissAge;
String k;
while ((nameCacheMissAges.size() > maxNameCacheMissSize) || (nameCacheMissAges.getMinScore() < cutofftime)) {
k = (String) nameCacheMissAges.getMinObject();
if (!nameCacheMiss.remove(k)) break; // ensure termination
nameCacheMissAges.deleteScore(k);
}
}
private static InetAddress[] localAddresses = null;
static {
try {
localAddresses = InetAddress.getAllByName(InetAddress.getLocalHost().getHostName());
} catch (UnknownHostException e) {
localAddresses = new InetAddress[0];
}
}
public static boolean isLocal(String address) {
// attention! because this method does a dns resolve to look up an IP address,
// the result may be very slow. Consider 100 milliseconds per access
assert (address != null);
// check local ip addresses
if (address.equals("localhost") || address.startsWith("127")
|| address.startsWith("192.168")
|| address.startsWith("10.")
|| address.startsWith("169.254")
||
// 172.16.0.0-172.31.255.255 (I think this is faster than a regex)
(address.startsWith("172.") && (address.startsWith("172.16.")
|| address.startsWith("172.17.")
|| address.startsWith("172.18.")
|| address.startsWith("172.19.")
|| address.startsWith("172.20.")
|| address.startsWith("172.21.")
|| address.startsWith("172.22.")
|| address.startsWith("172.23.")
|| address.startsWith("172.24.")
|| address.startsWith("172.25.")
|| address.startsWith("172.26.")
|| address.startsWith("172.27.")
|| address.startsWith("172.28.")
|| address.startsWith("172.29.")
|| address.startsWith("172.30.")
|| address.startsWith("172.31."))))
return true;
// make a dns resolve if a hostname is given and check again
final InetAddress clientAddress = dnsResolve(address);
if (clientAddress != null) {
if ((clientAddress.isAnyLocalAddress()) || (clientAddress.isLoopbackAddress())) return true;
if (address.charAt(0) > '9') address = clientAddress.getHostAddress();
}
// finally check if there are other local IP adresses that are not in
// the standard IP range
for (int i = 0; i < localAddresses.length; i++) {
if (localAddresses[i].equals(clientAddress)) return true;
}
// the address must be a global address
return false;
}
public static String myPublicIP() {
try {
// if a static IP was configured, we have to return it here ...
plasmaSwitchboard sb = plasmaSwitchboard.getSwitchboard();
if (sb != null) {
String staticIP = sb.getConfig("staticIP", "");
if ((!staticIP.equals(""))) {
return staticIP;
}
}
// If port forwarding was enabled we need to return the remote IP
// Address
if ((serverCore.portForwardingEnabled) && (serverCore.portForwarding != null)) {
// does not return serverCore.portForwarding.getHost(), because
// hostnames are not valid, except in DebugMode
return InetAddress.getByName(
serverCore.portForwarding.getHost()).getHostAddress();
}
// otherwise we return the real IP address of this host
InetAddress pLIP = myPublicLocalIP();
if (pLIP != null) return pLIP.getHostAddress();
return null;
} catch (java.net.UnknownHostException e) {
System.err.println("ERROR: (internal) " + e.getMessage());
return null;
}
}
public static InetAddress myPublicLocalIP() {
try {
String hostName;
try {
hostName = InetAddress.getLocalHost().getHostName();
} catch (java.net.UnknownHostException e) {
hostName = "localhost"; // hopin' nothing serious happened only the hostname changed while running yacy
System.err.println("ERROR: (internal) " + e.getMessage());
}
// list all addresses
InetAddress[] ia = InetAddress.getAllByName(hostName);
// for (int i = 0; i < ia.length; i++) System.out.println("IP: " +
// ia[i].getHostAddress()); // DEBUG
if (ia.length == 0) {
try {
return InetAddress.getLocalHost();
} catch (UnknownHostException e) {
try {
return InetAddress.getByName("127.0.0.1");
} catch (UnknownHostException ee) {
return null;
}
}
}
if (ia.length == 1) {
// only one network connection available
return ia[0];
}
// we have more addresses, find an address that is not local
int b0, b1;
for (int i = 0; i < ia.length; i++) {
b0 = 0Xff & ia[i].getAddress()[0];
b1 = 0Xff & ia[i].getAddress()[1];
if ((b0 != 10) && // class A reserved
(b0 != 127) && // loopback
((b0 != 172) || (b1 < 16) || (b1 > 31)) && // class B reserved
((b0 != 192) || (b1 != 168)) && // class C reserved
(ia[i].getHostAddress().indexOf(":") < 0))
return ia[i];
}
// there is only a local address, we filter out the possibly
// returned loopback address 127.0.0.1
for (int i = 0; i < ia.length; i++) {
if (((0Xff & ia[i].getAddress()[0]) != 127) && (ia[i].getHostAddress().indexOf(":") < 0)) return ia[i];
}
// if all fails, give back whatever we have
for (int i = 0; i < ia.length; i++) {
if (ia[i].getHostAddress().indexOf(":") < 0) return ia[i];
}
return ia[0];
} catch (java.net.UnknownHostException e) {
System.err.println("ERROR: (internal) " + e.getMessage());
return null;
}
}
}