// SurrogateReader.java
// (C) 2009 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// first published 15.04.2009 on http://yacy.net
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// 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 net.yacy.document.content;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PushbackInputStream;
import java.io.StringReader;
import java.net.MalformedURLException;
import java.nio.charset.StandardCharsets;
import java.util.Locale;
import java.util.Map;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.apache.solr.client.solrj.impl.XMLResponseParser;
import org.apache.solr.common.SolrDocument;
import org.apache.solr.common.SolrInputDocument;
import org.apache.solr.common.util.NamedList;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;
import net.yacy.cora.document.id.DigestURL;
import net.yacy.cora.lod.vocabulary.DublinCore;
import net.yacy.cora.lod.vocabulary.Geo;
import net.yacy.cora.util.ConcurrentLog;
import net.yacy.crawler.CrawlStacker;
import net.yacy.search.schema.CollectionConfiguration;
public class SurrogateReader extends DefaultHandler implements Runnable {
// definition of the surrogate main element
public final static String SURROGATES_MAIN_ELEMENT_NAME =
"surrogates";
public final static String SURROGATES_MAIN_ELEMENT_OPEN =
"<" + SURROGATES_MAIN_ELEMENT_NAME +
" xmlns:dc=\"" + DublinCore.NAMESPACE + "\"" +
" xmlns:yacy=\"http://yacy.net/\"" +
" xmlns:geo=\"" + Geo.NAMESPACE + "\">";
public final static String SURROGATES_MAIN_ELEMENT_CLOSE =
"</" + SURROGATES_MAIN_ELEMENT_NAME + ">";
public final static SolrInputDocument POISON_DOCUMENT = new SolrInputDocument();
/** Maximum bytes number that can be unread on the underlying input stream */
private static final int PUSHBACK_SIZE = 1024;
// class variables
private final StringBuilder buffer;
private boolean parsingValue;
private DCEntry dcEntry;
private String elementName;
/** Surrogates are either SolrInputDocument or DCEntry instances*/
private final BlockingQueue<Object> surrogates;
private SAXParser saxParser;
private final PushbackInputStream inputStream;
private final CrawlStacker crawlStacker;
private final CollectionConfiguration configuration;
private final int concurrency;
private static final ThreadLocal<SAXParser> tlSax = new ThreadLocal<SAXParser>();
private static SAXParser getParser() throws SAXException {
SAXParser parser = tlSax.get();
if (parser == null) {
try {
parser = SAXParserFactory.newInstance().newSAXParser();
} catch (final ParserConfigurationException e) {
throw new SAXException(e.getMessage(), e);
}
tlSax.set(parser);
}
return parser;
}
public SurrogateReader(final InputStream stream, int queueSize, CrawlStacker crawlStacker, CollectionConfiguration configuration, int concurrency) throws IOException {
this(new PushbackInputStream(stream, PUSHBACK_SIZE), queueSize, crawlStacker, configuration, concurrency);
}
public SurrogateReader(final PushbackInputStream stream, int queueSize, CrawlStacker crawlStacker, CollectionConfiguration configuration, int concurrency) throws IOException {
this.crawlStacker = crawlStacker;
this.configuration = configuration;
this.concurrency = concurrency;
this.buffer = new StringBuilder(300);
this.parsingValue = false;
this.dcEntry = null;
this.elementName = null;
this.surrogates = new ArrayBlockingQueue<>(queueSize);
this.inputStream = stream;
try {
this.saxParser = getParser();
} catch (final SAXException e) {
ConcurrentLog.logException(e);
throw new IOException(e.getMessage());
}
}
@Override
public void run() {
// test the syntax of the stream by reading parts of the beginning
try {
BufferedReader br = new BufferedReader(new InputStreamReader(this.inputStream, StandardCharsets.UTF_8));
if (isSolrDump()) {
String line;
while ((line = br.readLine()) != null) {
if (!line.startsWith("<doc>")) continue;
try {
NamedList<Object> nl = new XMLResponseParser().processResponse(new StringReader("<result>" + line + "</result>")); //
SolrDocument doc = (SolrDocument) nl.iterator().next().getValue();
// check if url is in accepted domain
String u = (String) doc.getFieldValue("sku");
if (u != null) {
try {
DigestURL url = new DigestURL(u);
final String urlRejectReason = this.crawlStacker.urlInAcceptedDomain(url);
if ( urlRejectReason == null ) {
// convert SolrDocument to SolrInputDocument
this.surrogates.put(this.configuration.toSolrInputDocument(doc));
}
} catch (MalformedURLException e) {
}
}
} catch (Throwable ee) {
// bad line
}
}
} else {
final InputSource inputSource = new InputSource(br);
inputSource.setEncoding(StandardCharsets.UTF_8.name());
this.saxParser.parse(inputSource, this);
}
} catch (final SAXParseException e) {
ConcurrentLog.logException(e);
} catch (final SAXException e) {
ConcurrentLog.logException(e);
} catch (final IOException e) {
ConcurrentLog.logException(e);
} finally {
for (int i = 0; i < this.concurrency; i++) {
try {
this.surrogates.put(POISON_DOCUMENT);
} catch (final InterruptedException e1) {
ConcurrentLog.logException(e1);
}
}
try {
this.inputStream.close();
} catch (final IOException e) {
ConcurrentLog.logException(e);
}
}
}
/**
* Check for format string in responseHeader "yacy.index.export.solr.xml"
* (introduced v1.92/9188 2017-04-30) or guess format by existing "<response>"
* and "<result>" or "<doc>" tag in the first {@value #PUSHBACK_SIZE} characters.
*
* @return true when inputStream is likely to contain a rich and full-text Solr xml data dump (see IndexExport_p.html)
*/
private boolean isSolrDump() {
boolean res = false;
byte[] b = new byte[PUSHBACK_SIZE];
int nbRead = -1;
try {
nbRead = this.inputStream.read(b);
if (nbRead > 0) {
String s = new String(b, 0, nbRead, StandardCharsets.UTF_8);
if (s.contains("format=\"yacy.index.export.solr.xml\"")) {
res = true;
} else if ((s.contains("<response>") && s.contains("<result>")) || s.startsWith("<doc>")) {
res = true;
}
}
} catch (IOException e) {
ConcurrentLog.logException(e);
} finally {
if (nbRead > 0) {
try {
this.inputStream.unread(b, 0, nbRead);
} catch (IOException e2) {
ConcurrentLog.logException(e2);
}
}
}
return res;
}
@Override
public void startElement(final String uri, final String name, String tag, final Attributes atts) throws SAXException {
if (tag == null) return;
tag = tag.toLowerCase(Locale.ROOT);
if ("record".equals(tag) || "document".equals(tag) || "doc".equals(tag)) {
this.dcEntry = new DCEntry();
} else if ("element".equals(tag) || "str".equals(tag) || "int".equals(tag) || "bool".equals(tag) || "long".equals(tag)) {
this.elementName = atts.getValue("name");
this.parsingValue = true;
} else if ("value".equals(tag)) {
this.buffer.setLength(0);
this.parsingValue = true;
} else if (tag.startsWith("dc:") || tag.startsWith("geo:") || tag.startsWith("md:")) {
// parse dublin core attribute
this.elementName = tag;
this.parsingValue = true;
}
}
@Override
public void endElement(final String uri, final String name, String tag) {
if (tag == null) return;
tag = tag.toLowerCase(Locale.ROOT);
if ("record".equals(tag) || "document".equals(tag) || "doc".equals(tag)) {
try {
// check if url is in accepted domain
final String urlRejectReason = this.crawlStacker.urlInAcceptedDomain(this.dcEntry.getIdentifier(true));
if ( urlRejectReason == null ) {
// DCEntry can not be converted to SolrInputDocument as DC schema has nothing to do with Solr collection schema
this.surrogates.put(this.dcEntry);
}
} catch (final InterruptedException e) {
ConcurrentLog.logException(e);
} finally {
this.dcEntry = null;
this.buffer.setLength(0);
this.parsingValue = false;
}
} else if ("element".equals(tag)) {
this.buffer.setLength(0);
this.parsingValue = false;
} else if ("str".equals(tag) || "int".equals(tag) || "bool".equals(tag) || "long".equals(tag)){
final String value = buffer.toString().trim();
if (this.elementName != null) {
this.dcEntry.getMap().put(this.elementName, new String[]{value});
}
this.buffer.setLength(0);
this.parsingValue = false;
} else if ("value".equals(tag)) {
final String value = buffer.toString().trim();
if (this.elementName != null) {
this.dcEntry.getMap().put(this.elementName, new String[]{value});
}
this.buffer.setLength(0);
this.parsingValue = false;
} else if (tag.startsWith("dc:") || tag.startsWith("geo:") || tag.startsWith("md:")) {
final String value = buffer.toString().trim();
if (this.elementName != null && tag.equals(this.elementName)) {
Map<String,String[]> map = this.dcEntry.getMap();
String[] oldcontent = map.get(this.elementName);
if (oldcontent == null || oldcontent.length == 0) {
map.put(this.elementName, new String[]{value});
} else {
String[] newcontent = new String[oldcontent.length + 1];
System.arraycopy(oldcontent, 0, newcontent, 0, oldcontent.length);
newcontent[oldcontent.length] = value;
map.put(this.elementName, newcontent);
}
}
this.buffer.setLength(0);
this.parsingValue = false;
}
}
@Override
public void characters(final char ch[], final int start, final int length) {
if (parsingValue) {
buffer.append(ch, start, length);
}
}
public Object take() {
try {
return this.surrogates.take();
} catch (final InterruptedException e) {
ConcurrentLog.logException(e);
return null;
}
}
}