You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
467 lines
20 KiB
467 lines
20 KiB
// plasmaSnippetCache.java
|
|
// -----------------------
|
|
// part of YaCy
|
|
// (C) by Michael Peter Christen; mc@anomic.de
|
|
// first published on http://www.anomic.de
|
|
// Frankfurt, Germany, 2005
|
|
// last major change: 07.06.2005
|
|
//
|
|
// 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
|
|
//
|
|
// Using this software in any meaning (reading, learning, copying, compiling,
|
|
// running) means that you agree that the Author(s) is (are) not responsible
|
|
// for cost, loss of data or any harm that may be caused directly or indirectly
|
|
// by usage of this softare or this documentation. The usage of this software
|
|
// is on your own risk. The installation and usage (starting/running) of this
|
|
// software may allow other people or application to access your computer and
|
|
// any attached devices and is highly dependent on the configuration of the
|
|
// software which must be done by the user of the software; the author(s) is
|
|
// (are) also not responsible for proper configuration and usage of the
|
|
// software, even if provoked by documentation provided together with
|
|
// the software.
|
|
//
|
|
// Any changes to this file according to the GPL as documented in the file
|
|
// gpl.txt aside this file in the shipment you received can be done to the
|
|
// lines that follows this copyright notice here, but changes must not be
|
|
// done inside the copyright notive above. A re-distribution must contain
|
|
// the intact and unchanged copyright notice.
|
|
// Contributions and changes to the program code must be marked as such.
|
|
|
|
|
|
package de.anomic.plasma;
|
|
|
|
import java.io.IOException;
|
|
import java.net.URL;
|
|
import java.util.Enumeration;
|
|
import java.util.HashMap;
|
|
import java.util.HashSet;
|
|
import java.util.Iterator;
|
|
import java.util.Set;
|
|
|
|
import de.anomic.http.httpHeader;
|
|
import de.anomic.kelondro.kelondroMScoreCluster;
|
|
import de.anomic.server.logging.serverLog;
|
|
import de.anomic.yacy.yacySearch;
|
|
import de.anomic.htmlFilter.htmlFilterContentScraper;
|
|
|
|
public class plasmaSnippetCache {
|
|
|
|
private static final int maxCache = 500;
|
|
|
|
public static final int SOURCE_CACHE = 0;
|
|
public static final int SOURCE_FILE = 1;
|
|
public static final int SOURCE_WEB = 2;
|
|
|
|
public static final int ERROR_NO_HASH_GIVEN = 11;
|
|
public static final int ERROR_SOURCE_LOADING = 12;
|
|
public static final int ERROR_RESOURCE_LOADING = 13;
|
|
public static final int ERROR_PARSER_FAILED = 14;
|
|
public static final int ERROR_PARSER_NO_LINES = 15;
|
|
public static final int ERROR_NO_MATCH = 16;
|
|
|
|
private int snippetsScoreCounter;
|
|
private kelondroMScoreCluster snippetsScore;
|
|
private HashMap snippetsCache;
|
|
private plasmaHTCache cacheManager;
|
|
private plasmaParser parser;
|
|
private serverLog log;
|
|
private plasmaSwitchboard sb;
|
|
|
|
public plasmaSnippetCache(
|
|
plasmaSwitchboard theSb,
|
|
plasmaHTCache cacheManager,
|
|
plasmaParser parser,
|
|
serverLog log
|
|
) {
|
|
this.cacheManager = cacheManager;
|
|
this.parser = parser;
|
|
this.log = log;
|
|
this.sb = theSb;
|
|
this.snippetsScoreCounter = 0;
|
|
this.snippetsScore = new kelondroMScoreCluster();
|
|
this.snippetsCache = new HashMap();
|
|
}
|
|
|
|
public class result {
|
|
private String line;
|
|
private String error;
|
|
private int source;
|
|
public result(String line, int source, String errortext) {
|
|
this.line = line;
|
|
this.source = source;
|
|
this.error = errortext;
|
|
}
|
|
public boolean exists() {
|
|
return line != null;
|
|
}
|
|
public String toString() {
|
|
return (line == null) ? "" : line;
|
|
}
|
|
public String getLineRaw() {
|
|
return (line == null) ? "" : line;
|
|
}
|
|
public String getError() {
|
|
return (error == null) ? "" : error.trim();
|
|
}
|
|
public String getLineMarked(Set queryHashes) {
|
|
if (line == null) return "";
|
|
if ((queryHashes == null) || (queryHashes.size() == 0)) return line.trim();
|
|
if (line.endsWith(".")) line = line.substring(0, line.length() - 1);
|
|
Iterator i = queryHashes.iterator();
|
|
String h;
|
|
String[] w = line.split(" ");
|
|
while (i.hasNext()) {
|
|
h = (String) i.next();
|
|
for (int j = 0; j < w.length; j++) {
|
|
if (plasmaWordIndexEntry.word2hash(w[j]).equals(h)) w[j] = "<b>" + w[j] + "</b>";
|
|
}
|
|
}
|
|
StringBuffer l = new StringBuffer(line.length() + queryHashes.size() * 8);
|
|
for (int j = 0; j < w.length; j++) {
|
|
l.append(w[j]);
|
|
l.append(' ');
|
|
}
|
|
return l.toString().trim();
|
|
}
|
|
public int getSource() {
|
|
return source;
|
|
}
|
|
}
|
|
|
|
public boolean existsInCache(URL url, Set queryhashes) {
|
|
String hashes = yacySearch.set2string(queryhashes);
|
|
return retrieveFromCache(hashes, plasmaURL.urlHash(url)) != null;
|
|
}
|
|
|
|
public result retrieve(URL url, Set queryhashes, boolean fetchOnline, int snippetMaxLength) {
|
|
// heise = "0OQUNU3JSs05"
|
|
if (queryhashes.size() == 0) {
|
|
//System.out.println("found no queryhashes for URL retrieve " + url);
|
|
return new result(null, ERROR_NO_HASH_GIVEN, "no query hashes given");
|
|
}
|
|
String urlhash = plasmaURL.urlHash(url);
|
|
|
|
// try to get snippet from snippetCache
|
|
int source = SOURCE_CACHE;
|
|
String wordhashes = yacySearch.set2string(queryhashes);
|
|
String line = retrieveFromCache(wordhashes, urlhash);
|
|
if (line != null) {
|
|
//System.out.println("found snippet for URL " + url + " in cache: " + line);
|
|
return new result(line, source, null);
|
|
}
|
|
|
|
// if the snippet is not in the cache, we can try to get it from the htcache
|
|
byte[] resource = null;
|
|
httpHeader header = null;
|
|
try {
|
|
resource = cacheManager.loadResource(url);
|
|
if ((fetchOnline) && (resource == null)) {
|
|
plasmaHTCache.Entry entry = loadResourceFromWeb(url, 5000);
|
|
if (entry != null) {
|
|
header = entry.responseHeader;
|
|
}
|
|
resource = cacheManager.loadResource(url);
|
|
source = SOURCE_WEB;
|
|
}
|
|
} catch (IOException e) {
|
|
return new result(null, ERROR_SOURCE_LOADING, "error loading resource from web: " + e.getMessage());
|
|
}
|
|
if (resource == null) {
|
|
//System.out.println("cannot load document for URL " + url);
|
|
return new result(null, ERROR_RESOURCE_LOADING, "error loading resource from web, cacheManager returned NULL");
|
|
}
|
|
plasmaParserDocument document = parseDocument(url, resource, header);
|
|
|
|
if (document == null) return new result(null, ERROR_PARSER_FAILED, "parser error/failed"); // cannot be parsed
|
|
//System.out.println("loaded document for URL " + url);
|
|
String[] sentences = document.getSentences();
|
|
//System.out.println("----" + url.toString()); for (int l = 0; l < sentences.length; l++) System.out.println(sentences[l]);
|
|
if ((sentences == null) || (sentences.length == 0)) {
|
|
//System.out.println("found no sentences in url " + url);
|
|
return new result(null, ERROR_PARSER_NO_LINES, "parser returned no sentences");
|
|
}
|
|
|
|
// we have found a parseable non-empty file: use the lines
|
|
line = computeSnippet(sentences, queryhashes, 8 + 6 * queryhashes.size(), snippetMaxLength);
|
|
//System.out.println("loaded snippet for URL " + url + ": " + line);
|
|
if (line == null) return new result(null, ERROR_NO_MATCH, "no matching snippet found");
|
|
if (line.length() > snippetMaxLength) line = line.substring(0, snippetMaxLength);
|
|
|
|
// finally store this snippet in our own cache
|
|
storeToCache(wordhashes, urlhash, line);
|
|
return new result(line, source, null);
|
|
}
|
|
|
|
public void storeToCache(String wordhashes, String urlhash, String snippet) {
|
|
// generate key
|
|
String key = urlhash + wordhashes;
|
|
|
|
// do nothing if snippet is known
|
|
if (snippetsCache.containsKey(key)) return;
|
|
|
|
// learn new snippet
|
|
snippetsScore.addScore(key, snippetsScoreCounter++);
|
|
snippetsCache.put(key, snippet);
|
|
|
|
// care for counter
|
|
if (snippetsScoreCounter == java.lang.Integer.MAX_VALUE) {
|
|
snippetsScoreCounter = 0;
|
|
snippetsScore = new kelondroMScoreCluster();
|
|
snippetsCache = new HashMap();
|
|
}
|
|
|
|
// flush cache if cache is full
|
|
while (snippetsCache.size() > maxCache) {
|
|
key = (String) snippetsScore.getMinObject();
|
|
snippetsScore.deleteScore(key);
|
|
snippetsCache.remove(key);
|
|
}
|
|
}
|
|
|
|
private String retrieveFromCache(String wordhashes, String urlhash) {
|
|
// generate key
|
|
String key = urlhash + wordhashes;
|
|
return (String) snippetsCache.get(key);
|
|
}
|
|
|
|
private String computeSnippet(String[] sentences, Set queryhashes, int minLength, int maxLength) {
|
|
try {
|
|
if ((sentences == null) || (sentences.length == 0)) return null;
|
|
if ((queryhashes == null) || (queryhashes.size() == 0)) return null;
|
|
kelondroMScoreCluster hitTable = new kelondroMScoreCluster();
|
|
Iterator j;
|
|
HashMap hs;
|
|
String hash;
|
|
for (int i = 0; i < sentences.length; i++) {
|
|
//System.out.println("Sentence " + i + ": " + sentences[i]);
|
|
if (sentences[i].length() > minLength) {
|
|
hs = hashSentence(sentences[i]);
|
|
j = queryhashes.iterator();
|
|
while (j.hasNext()) {
|
|
hash = (String) j.next();
|
|
if (hs.containsKey(hash)) {
|
|
//System.out.println("hash " + hash + " appears in line " + i);
|
|
hitTable.incScore(new Integer(i));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
int score = hitTable.getMaxScore(); // best number of hits
|
|
if (score <= 0) return null;
|
|
// we found (a) line(s) that have <score> hits.
|
|
// now find the shortest line of these hits
|
|
int shortLineIndex = -1;
|
|
int shortLineLength = Integer.MAX_VALUE;
|
|
for (int i = 0; i < sentences.length; i++) {
|
|
if ((hitTable.getScore(new Integer(i)) == score) &&
|
|
(sentences[i].length() < shortLineLength)) {
|
|
shortLineIndex = i;
|
|
shortLineLength = sentences[i].length();
|
|
}
|
|
}
|
|
// find a first result
|
|
String result = sentences[shortLineIndex];
|
|
// remove all hashes that appear in the result
|
|
hs = hashSentence(result);
|
|
j = queryhashes.iterator();
|
|
Integer pos;
|
|
Set remaininghashes = new HashSet();
|
|
int p, minpos = result.length(), maxpos = -1;
|
|
while (j.hasNext()) {
|
|
hash = (String) j.next();
|
|
pos = (Integer) hs.get(hash);
|
|
if (pos == null) {
|
|
remaininghashes.add(new String(hash));
|
|
} else {
|
|
p = pos.intValue();
|
|
if (p > maxpos) maxpos = p;
|
|
if (p < minpos) minpos = p;
|
|
}
|
|
}
|
|
// check result size
|
|
maxpos = maxpos + 10;
|
|
if (maxpos > result.length()) maxpos = result.length();
|
|
if (minpos < 0) minpos = 0;
|
|
// we have a result, but is it short enough?
|
|
if (maxpos - minpos + 10 > maxLength) {
|
|
// the string is too long, even if we cut at both ends
|
|
// so cut here in the middle of the string
|
|
int lenb = result.length();
|
|
result = result.substring(0, (minpos + 20 > result.length()) ? result.length() : minpos + 20).trim() +
|
|
" [..] " +
|
|
result.substring((maxpos + 26 > result.length()) ? result.length() : maxpos + 26).trim();
|
|
maxpos = maxpos + lenb - result.length() + 6;
|
|
}
|
|
if (maxpos > maxLength) {
|
|
// the string is too long, even if we cut it at the end
|
|
// so cut it here at both ends at once
|
|
int newlen = maxpos - minpos + 10;
|
|
int around = (maxLength - newlen) / 2;
|
|
result = "[..] " + result.substring(minpos - around, ((maxpos + around) > result.length()) ? result.length() : (maxpos + around)).trim() + " [..]";
|
|
minpos = around;
|
|
maxpos = result.length() - around - 5;
|
|
}
|
|
if (result.length() > maxLength) {
|
|
// trim result, 1st step (cut at right side)
|
|
result = result.substring(0, maxpos).trim() + " [..]";
|
|
}
|
|
if (result.length() > maxLength) {
|
|
// trim result, 2nd step (cut at left side)
|
|
result = "[..] " + result.substring(minpos).trim();
|
|
}
|
|
if (result.length() > maxLength) {
|
|
// trim result, 3rd step (cut in the middle)
|
|
result = result.substring(6, 20).trim() + " [..] " + result.substring(result.length() - 26, result.length() - 6).trim();
|
|
}
|
|
if (queryhashes.size() == 0) return result;
|
|
// the result has not all words in it.
|
|
// find another sentence that represents the missing other words
|
|
// and find recursively more sentences
|
|
maxLength = maxLength - result.length();
|
|
if (maxLength < 20) maxLength = 20;
|
|
String nextSnippet = computeSnippet(sentences, remaininghashes, minLength, maxLength);
|
|
return result + ((nextSnippet == null) ? "" : (" / " + nextSnippet));
|
|
} catch (IndexOutOfBoundsException e) {
|
|
log.logSevere("computeSnippet: error with string generation", e);
|
|
return "";
|
|
}
|
|
}
|
|
|
|
private HashMap hashSentence(String sentence) {
|
|
// generates a word-wordPos mapping
|
|
HashMap map = new HashMap();
|
|
Enumeration words = plasmaCondenser.wordTokenizer(sentence, 0);
|
|
int pos = 0;
|
|
String word;
|
|
while (words.hasMoreElements()) {
|
|
word = (String) words.nextElement();
|
|
map.put(plasmaWordIndexEntry.word2hash(word), new Integer(pos));
|
|
pos += word.length() + 1;
|
|
}
|
|
return map;
|
|
}
|
|
|
|
public plasmaParserDocument parseDocument(URL url, byte[] resource) {
|
|
return parseDocument(url, resource, null);
|
|
}
|
|
|
|
public plasmaParserDocument parseDocument(URL url, byte[] resource, httpHeader header) {
|
|
if (resource == null) return null;
|
|
|
|
if (header == null) {
|
|
try {
|
|
header = this.cacheManager.getCachedResponse(plasmaURL.urlHash(url));
|
|
} catch (IOException e) {}
|
|
}
|
|
|
|
if (header == null) {
|
|
String filename = this.cacheManager.getCachePath(url).getName();
|
|
int p = filename.lastIndexOf('.');
|
|
if ( // if no extension is available
|
|
(p < 0) ||
|
|
// or the extension is supported by one of the parsers
|
|
((p >= 0) && (plasmaParser.supportedFileExtContains(filename.substring(p + 1))))
|
|
) {
|
|
String supposedMime = "text/html";
|
|
|
|
// if the mimeType Parser is installed we can set the mimeType to null to force
|
|
// a mimetype detection
|
|
if (plasmaParser.supportedMimeTypesContains("application/octet-stream")) {
|
|
supposedMime = null;
|
|
} else if (p != -1){
|
|
// otherwise we try to determine the mimeType per file Extension
|
|
supposedMime = plasmaParser.getMimeTypeByFileExt(filename.substring(p + 1));
|
|
}
|
|
|
|
return this.parser.parseSource(url, supposedMime, resource);
|
|
} else {
|
|
return null;
|
|
}
|
|
} else {
|
|
if (plasmaParser.supportedMimeTypesContains(header.mime())) {
|
|
return this.parser.parseSource(url, header.mime(), resource);
|
|
} else {
|
|
return null;
|
|
}
|
|
}
|
|
}
|
|
|
|
public byte[] getResource(URL url, boolean fetchOnline, int socketTimeout) {
|
|
// load the url as resource from the web
|
|
try {
|
|
byte[] resource = cacheManager.loadResource(url);
|
|
if ((fetchOnline) && (resource == null)) {
|
|
loadResourceFromWeb(url, (socketTimeout < 0) ? -1 : socketTimeout);
|
|
resource = cacheManager.loadResource(url);
|
|
}
|
|
return resource;
|
|
} catch (IOException e) {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
public plasmaHTCache.Entry loadResourceFromWeb(URL url, int socketTimeout) throws IOException {
|
|
return plasmaCrawlWorker.load(
|
|
url,
|
|
"",
|
|
null,
|
|
null,
|
|
0,
|
|
null,
|
|
socketTimeout,
|
|
this.sb.remoteProxyConfig,
|
|
this.cacheManager,
|
|
true,
|
|
this.log);
|
|
}
|
|
|
|
public void fetch(plasmaSearchResult acc, Set queryhashes, String urlmask, int fetchcount, long maxTime) {
|
|
// fetch snippets
|
|
int i = 0;
|
|
plasmaCrawlLURL.Entry urlentry;
|
|
String urlstring;
|
|
long limitTime = (maxTime < 0) ? Long.MAX_VALUE : System.currentTimeMillis() + maxTime;
|
|
while ((acc.hasMoreElements()) && (i < fetchcount) && (System.currentTimeMillis() < limitTime)) {
|
|
urlentry = acc.nextElement();
|
|
if (urlentry.url().getHost().endsWith(".yacyh")) continue;
|
|
urlstring = htmlFilterContentScraper.urlNormalform(urlentry.url());
|
|
if ((urlstring.matches(urlmask)) &&
|
|
(!(existsInCache(urlentry.url(), queryhashes)))) {
|
|
new Fetcher(urlentry.url(), queryhashes).start();
|
|
i++;
|
|
}
|
|
}
|
|
}
|
|
|
|
public class Fetcher extends Thread {
|
|
URL url;
|
|
Set queryhashes;
|
|
public Fetcher(URL url, Set queryhashes) {
|
|
if (url.getHost().endsWith(".yacyh")) return;
|
|
this.url = url;
|
|
this.queryhashes = queryhashes;
|
|
}
|
|
public void run() {
|
|
log.logFine("snippetFetcher: try to get URL " + url);
|
|
plasmaSnippetCache.result snippet = retrieve(url, queryhashes, true, 260);
|
|
if (snippet.line == null)
|
|
log.logFine("snippetFetcher: cannot get URL " + url + ". error(" + snippet.source + "): " + snippet.error);
|
|
else
|
|
log.logFine("snippetFetcher: got URL " + url + ", the snippet is '" + snippet.line + "', source=" + snippet.source);
|
|
}
|
|
}
|
|
|
|
}
|