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* 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.
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package org.apache.solr.spelling;
import static org.apache.solr.common.params.CommonParams.ID;
import java.lang.invoke.MethodHandles;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import org.apache.lucene.analysis.Token;
import org.apache.lucene.index.IndexReader;
import org.apache.solr.common.params.CommonParams;
import org.apache.solr.common.params.CursorMarkParams;
import org.apache.solr.common.params.DisMaxParams;
import org.apache.solr.common.params.GroupParams;
import org.apache.solr.common.params.ModifiableSolrParams;
import org.apache.solr.common.params.SolrParams;
import org.apache.solr.common.params.SpellingParams;
import org.apache.solr.common.util.NamedList;
import org.apache.solr.handler.component.QueryComponent;
import org.apache.solr.handler.component.ResponseBuilder;
import org.apache.solr.handler.component.SearchComponent;
import org.apache.solr.request.LocalSolrQueryRequest;
import org.apache.solr.response.SolrQueryResponse;
import org.apache.solr.search.EarlyTerminatingCollectorException;
import org.apache.solr.search.SolrIndexSearcher;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class SpellCheckCollator {
private static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
private int maxCollations = 1;
private int maxCollationTries = 0;
private int maxCollationEvaluations = 10000;
private boolean suggestionsMayOverlap = false;
private int docCollectionLimit = 0;
public List<SpellCheckCollation> collate(SpellingResult result,
String originalQuery, ResponseBuilder ultimateResponse) {
List<SpellCheckCollation> collations = new ArrayList<>();
QueryComponent queryComponent = null;
if (ultimateResponse.components != null) {
for (SearchComponent sc : ultimateResponse.components) {
if (sc instanceof QueryComponent) {
queryComponent = (QueryComponent) sc;
break;
}
}
}
boolean verifyCandidateWithQuery = true;
int maxTries = maxCollationTries;
int maxNumberToIterate = maxTries;
if (maxTries < 1) {
maxTries = 1;
maxNumberToIterate = maxCollations;
verifyCandidateWithQuery = false;
}
if (queryComponent == null && verifyCandidateWithQuery) {
LOG.info("Could not find an instance of QueryComponent. Disabling collation verification against the index.");
maxTries = 1;
verifyCandidateWithQuery = false;
}
docCollectionLimit = docCollectionLimit > 0 ? docCollectionLimit : 0;
int maxDocId = -1;
if (verifyCandidateWithQuery && docCollectionLimit > 0) {
IndexReader reader = ultimateResponse.req.getSearcher().getIndexReader();
maxDocId = reader.maxDoc();
}
int tryNo = 0;
int collNo = 0;
PossibilityIterator possibilityIter = new PossibilityIterator(result.getSuggestions(),
maxNumberToIterate, maxCollationEvaluations, suggestionsMayOverlap);
while (tryNo < maxTries && collNo < maxCollations && possibilityIter.hasNext()) {
PossibilityIterator.RankedSpellPossibility possibility = possibilityIter.next();
String collationQueryStr = getCollation(originalQuery, possibility.corrections);
int hits = 0;
if (verifyCandidateWithQuery) {
tryNo++;
SolrParams origParams = ultimateResponse.req.getParams();
ModifiableSolrParams params = new ModifiableSolrParams(origParams);
Iterator<String> origParamIterator = origParams.getParameterNamesIterator();
int pl = SpellingParams.SPELLCHECK_COLLATE_PARAM_OVERRIDE.length();
while (origParamIterator.hasNext()) {
String origParamName = origParamIterator.next();
if (origParamName
.startsWith(SpellingParams.SPELLCHECK_COLLATE_PARAM_OVERRIDE)
&& origParamName.length() > pl) {
String[] val = origParams.getParams(origParamName);
if (val.length == 1 && val[0].length() == 0) {
params.set(origParamName.substring(pl), (String[]) null);
} else {
params.set(origParamName.substring(pl), val);
}
}
}
params.set(CommonParams.Q, collationQueryStr);
params.remove(CommonParams.START);
params.set(CommonParams.ROWS, "" + docCollectionLimit);
// we don't want any stored fields
params.set(CommonParams.FL, ID);
// we'll sort by doc id to ensure no scoring is done.
params.set(CommonParams.SORT, "_docid_ asc");
// CursorMark does not like _docid_ sorting, and we don't need it.
params.remove(CursorMarkParams.CURSOR_MARK_PARAM);
// If a dismax query, don't add unnecessary clauses for scoring
params.remove(DisMaxParams.TIE);
params.remove(DisMaxParams.PF);
params.remove(DisMaxParams.PF2);
params.remove(DisMaxParams.PF3);
params.remove(DisMaxParams.BQ);
params.remove(DisMaxParams.BF);
// Collate testing does not support Grouping (see SOLR-2577)
params.remove(GroupParams.GROUP);
// Collate testing does not support the Collapse QParser (See SOLR-8807)
params.remove("expand");
String[] filters = params.getParams(CommonParams.FQ);
if (filters != null) {
List<String> filtersToApply = new ArrayList<>(filters.length);
for (String fq : filters) {
if (!fq.startsWith("{!collapse")) {
filtersToApply.add(fq);
}
}
params.set("fq", filtersToApply.toArray(new String[filtersToApply.size()]));
}
// creating a request here... make sure to close it!
ResponseBuilder checkResponse = new ResponseBuilder(
new LocalSolrQueryRequest(ultimateResponse.req.getCore(), params),
new SolrQueryResponse(), Arrays.<SearchComponent> asList(queryComponent));
checkResponse.setQparser(ultimateResponse.getQparser());
checkResponse.setFilters(ultimateResponse.getFilters());
checkResponse.setQueryString(collationQueryStr);
checkResponse.components = Arrays.<SearchComponent>asList(queryComponent);
try {
queryComponent.prepare(checkResponse);
if (docCollectionLimit > 0) {
int f = checkResponse.getFieldFlags();
checkResponse.setFieldFlags(f |= SolrIndexSearcher.TERMINATE_EARLY);
}
queryComponent.process(checkResponse);
hits = (Integer) checkResponse.rsp.getToLog().get("hits");
} catch (EarlyTerminatingCollectorException etce) {
assert (docCollectionLimit > 0);
assert 0 < etce.getNumberScanned();
assert 0 < etce.getNumberCollected();
if (etce.getNumberScanned() == maxDocId) {
hits = etce.getNumberCollected();
} else {
hits = (int) ( ((float)( maxDocId * etce.getNumberCollected() ))
/ (float)etce.getNumberScanned() );
}
} catch (Exception e) {
LOG.warn("Exception trying to re-query to check if a spell check possibility would return any hits.", e);
} finally {
checkResponse.req.close();
}
}
if (hits > 0 || !verifyCandidateWithQuery) {
collNo++;
SpellCheckCollation collation = new SpellCheckCollation();
collation.setCollationQuery(collationQueryStr);
collation.setHits(hits);
collation.setInternalRank(suggestionsMayOverlap ? ((possibility.rank * 1000) + possibility.index) : possibility.rank);
NamedList<String> misspellingsAndCorrections = new NamedList<>();
for (SpellCheckCorrection corr : possibility.corrections) {
misspellingsAndCorrections.add(corr.getOriginal().toString(), corr.getCorrection());
}
collation.setMisspellingsAndCorrections(misspellingsAndCorrections);
collations.add(collation);
}
if (LOG.isDebugEnabled()) {
LOG.debug("Collation: " + collationQueryStr + (verifyCandidateWithQuery ? (" will return " + hits + " hits.") : ""));
}
}
return collations;
}
private String getCollation(String origQuery,
List<SpellCheckCorrection> corrections) {
StringBuilder collation = new StringBuilder(origQuery);
int offset = 0;
String corr = "";
for(int i=0 ; i<corrections.size() ; i++) {
SpellCheckCorrection correction = corrections.get(i);
Token tok = correction.getOriginal();
// we are replacing the query in order, but injected terms might cause
// illegal offsets due to previous replacements.
if (tok.getPositionIncrement() == 0)
continue;
corr = correction.getCorrection();
boolean addParenthesis = false;
Character requiredOrProhibited = null;
int indexOfSpace = corr.indexOf(' ');
StringBuilder corrSb = new StringBuilder(corr);
int bump = 1;
//If the correction contains whitespace (because it involved breaking a word in 2+ words),
//then be sure all of the new words have the same optional/required/prohibited status in the query.
while(indexOfSpace>-1 && indexOfSpace<corr.length()-1) {
addParenthesis = true;
char previousChar = tok.startOffset()>0 ? origQuery.charAt(tok.startOffset()-1) : ' ';
if(previousChar=='-' || previousChar=='+') {
corrSb.insert(indexOfSpace + bump, previousChar);
if(requiredOrProhibited==null) {
requiredOrProhibited = previousChar;
}
bump++;
} else if ((tok.getFlags() & QueryConverter.TERM_IN_BOOLEAN_QUERY_FLAG) == QueryConverter.TERM_IN_BOOLEAN_QUERY_FLAG) {
corrSb.insert(indexOfSpace + bump, "AND ");
bump += 4;
}
indexOfSpace = correction.getCorrection().indexOf(' ', indexOfSpace + bump);
}
int oneForReqOrProhib = 0;
if(addParenthesis) {
if(requiredOrProhibited!=null) {
corrSb.insert(0, requiredOrProhibited);
oneForReqOrProhib++;
}
corrSb.insert(0, '(');
corrSb.append(')');
}
corr = corrSb.toString();
int startIndex = tok.startOffset() + offset - oneForReqOrProhib;
int endIndex = tok.endOffset() + offset;
collation.replace(startIndex, endIndex, corr);
offset += corr.length() - oneForReqOrProhib - (tok.endOffset() - tok.startOffset());
}
return collation.toString();
}
public SpellCheckCollator setMaxCollations(int maxCollations) {
this.maxCollations = maxCollations;
return this;
}
public SpellCheckCollator setMaxCollationTries(int maxCollationTries) {
this.maxCollationTries = maxCollationTries;
return this;
}
public SpellCheckCollator setMaxCollationEvaluations(
int maxCollationEvaluations) {
this.maxCollationEvaluations = maxCollationEvaluations;
return this;
}
public SpellCheckCollator setSuggestionsMayOverlap(
boolean suggestionsMayOverlap) {
this.suggestionsMayOverlap = suggestionsMayOverlap;
return this;
}
public SpellCheckCollator setDocCollectionLimit(int docCollectionLimit) {
this.docCollectionLimit = docCollectionLimit;
return this;
}
}