// plasmaHTCache.java
// -----------------------
// part of YaCy
// (C) by Michael Peter Christen; mc@yacy.net
// first published on http://www.anomic.de
// Frankfurt, Germany, 2004
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// 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
/*
Class documentation:
This class has two purposes:
1. provide a object that carries path and header information
that shall be used as objects within a scheduler's stack
2. static methods for a cache control and cache aging
the class shall also be used to do a cache-cleaning and index creation
*/
package de.anomic.plasma;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import de.anomic.http.httpResponseHeader;
import de.anomic.index.indexDocumentMetadata;
import de.anomic.kelondro.kelondroBLOB;
import de.anomic.kelondro.kelondroBLOBArray;
import de.anomic.kelondro.kelondroBLOBBuffer;
import de.anomic.kelondro.kelondroBLOBHeap;
import de.anomic.kelondro.kelondroBase64Order;
import de.anomic.kelondro.kelondroMap;
import de.anomic.server.serverFileUtils;
import de.anomic.server.logging.serverLog;
import de.anomic.yacy.yacySeedDB;
import de.anomic.yacy.yacyURL;
public final class plasmaHTCache {
public static final String RESPONSE_HEADER_DB_NAME = "responseHeader.heap";
public static final String FILE_DB_NAME = "file.array";
public static final long oneday = 1000L * 60L * 60L * 24L; // milliseconds of a day
private static kelondroMap responseHeaderDB = null;
private static kelondroBLOBBuffer fileDB = null;
private static kelondroBLOBArray fileDBunbuffered = null;
public static long maxCacheSize = 0l;
public static File cachePath = null;
public static final serverLog log = new serverLog("HTCACHE");
// URL attributes
public static final int UA_LOCAL = 0; // URL was crawled locally
public static final int UA_TILDE = 1; // tilde appears in URL
public static final int UA_REDIRECT = 2; // The URL is a redirection
// local flag attributes
public static final char LT_LOCAL = 'L';
public static final char LT_GLOBAL = 'G';
public static void init(final File htCachePath, final long CacheSizeMax) {
cachePath = htCachePath;
maxCacheSize = CacheSizeMax;
// reset old HTCache ?
String[] list = cachePath.list();
if (list != null) {
File object;
for (int i = list.length - 1; i >= 0; i--) {
object = new File(cachePath, list[i]);
if (object.getName().equals("http") ||
object.getName().equals("yacy") ||
object.getName().equals("https") ||
object.getName().equals("ftp")) {
serverFileUtils.deleteDirectory(cachePath);
}
}
}
// set/make cache path
if (!htCachePath.exists()) {
htCachePath.mkdirs();
}
if (!htCachePath.isDirectory()) {
// if the cache does not exists or is a file and not a directory, panic
log.logSevere("the cache path " + htCachePath.toString() + " is not a directory or does not exists and cannot be created");
System.exit(0);
}
// open the response header database
openDB();
}
static void resetDB() {
log.logFine("reset responseHeader DB with "+ responseHeaderDB.size() +" entries");
if (responseHeaderDB != null) responseHeaderDB.close();
final File dbfile = new File(cachePath, RESPONSE_HEADER_DB_NAME);
if (dbfile.exists()) dbfile.delete();
openDB();
}
private static void openDB() {
// open the response header database
final File dbfile = new File(cachePath, RESPONSE_HEADER_DB_NAME);
kelondroBLOB blob = null;
try {
blob = new kelondroBLOBHeap(dbfile, yacySeedDB.commonHashLength, kelondroBase64Order.enhancedCoder);
} catch (final IOException e) {
e.printStackTrace();
}
responseHeaderDB = new kelondroMap(blob, 500);
try {
fileDBunbuffered = new kelondroBLOBArray(new File(cachePath, FILE_DB_NAME), 12, kelondroBase64Order.enhancedCoder);
fileDBunbuffered.setMaxSize(maxCacheSize);
fileDB = new kelondroBLOBBuffer(fileDBunbuffered, 2 * 1024 * 1024, true);
} catch (IOException e) {
e.printStackTrace();
}
}
public static int responseHeaderDBSize() {
return responseHeaderDB.size();
}
public static long fileDBSize() {
return fileDB.length();
}
/**
* This method changes the HTCache size.<br>
* @param the new cache size in bytes
*/
public static void setCacheSize(final long newCacheSize) {
maxCacheSize = newCacheSize;
fileDBunbuffered.setMaxSize(maxCacheSize);
}
/**
* This method returns the free HTCache size.<br>
* @return the cache size in bytes
*/
public static long getFreeSize() {
long l = fileDB.length();
return (l >= maxCacheSize) ? 0 : maxCacheSize - l;
}
public static void close() {
responseHeaderDB.close();
fileDB.close();
}
public static boolean isPicture(final String mimeType) {
if (mimeType == null) return false;
return mimeType.toUpperCase().startsWith("IMAGE");
}
public static boolean isText(final String mimeType) {
return plasmaParser.supportedMimeTypesContains(mimeType);
}
public static boolean noIndexingURL(final yacyURL url) {
if (url == null) return false;
String urlString = url.toString().toLowerCase();
//http://www.yacy.net/getimage.php?image.png
int idx = urlString.indexOf("?");
if (idx > 0) urlString = urlString.substring(0,idx);
//http://www.yacy.net/getimage.php
idx = urlString.lastIndexOf(".");
if (idx > 0) urlString = urlString.substring(idx+1);
//php
return plasmaParser.mediaExtContains(urlString);
}
// Store to Cache
public static void storeMetadata(
final httpResponseHeader responseHeader,
indexDocumentMetadata metadata
) {
if (responseHeader != null) try {
// store the response header into the header database
final HashMap<String, String> hm = new HashMap<String, String>();
hm.putAll(responseHeader);
hm.put("@@URL", metadata.url().toNormalform(false, false));
hm.put("@@DEPTH", Integer.toString(metadata.depth()));
responseHeaderDB.put(metadata.urlHash(), hm);
} catch (final Exception e) {
log.logWarning("could not write ResourceInfo: "
+ e.getClass() + ": " + e.getMessage());
resetDB();
}
}
public static void storeFile(yacyURL url, byte[] file) {
try {
fileDB.put(url.hash().getBytes("UTF-8"), file);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* Returns an object containing metadata about a cached resource
* @param url the {@link URL} of the resource
* @return an {@link IResourceInfo info object}
* @throws <b>IllegalAccessException</b> if the {@link SecurityManager} doesn't allow instantiation
* of the info object with the given protocol
* @throws <b>UnsupportedProtocolException</b> if the protocol is not supported and therefore the
* info object couldn't be created
*/
public static httpResponseHeader loadResponseHeader(final yacyURL url) throws IllegalAccessException {
// loading data from database
Map<String, String> hdb;
try {
hdb = responseHeaderDB.get(url.hash());
} catch (final IOException e) {
return null;
}
if (hdb == null) return null;
return new httpResponseHeader(null, hdb);
}
/**
* Returns the content of a cached resource as {@link InputStream}
* @param url the requested resource
* @return the resource content as {@link InputStream}. In no data
* is available or the cached file is not readable, <code>null</code>
* is returned.
*/
public static InputStream getResourceContentStream(final yacyURL url) {
// load the url as resource from the cache
byte[] b = getResourceContent(url);
if (b == null) return null;
return new ByteArrayInputStream(b);
}
public static byte[] getResourceContent(final yacyURL url) {
// load the url as resource from the cache
try {
return fileDB.get(url.hash().getBytes("UTF-8"));
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
public static long getResourceContentLength(final yacyURL url) {
// load the url as resource from the cache
try {
return fileDB.length(url.hash().getBytes("UTF-8"));
} catch (IOException e) {
e.printStackTrace();
return -1;
}
}
public static void deleteFromCache(yacyURL url) throws IOException {
responseHeaderDB.remove(url.hash());
fileDB.remove(url.hash().getBytes("UTF-8"));
}
}