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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing,
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package org.elasticsearch.search.suggest.phrase;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.LowerCaseFilter;
import org.apache.lucene.analysis.TokenFilter;
import org.apache.lucene.analysis.Tokenizer;
import org.apache.lucene.analysis.core.WhitespaceAnalyzer;
import org.apache.lucene.analysis.miscellaneous.PerFieldAnalyzerWrapper;
import org.apache.lucene.analysis.reverse.ReverseStringFilter;
import org.apache.lucene.analysis.shingle.ShingleFilter;
import org.apache.lucene.analysis.standard.StandardTokenizer;
import org.apache.lucene.analysis.synonym.SolrSynonymParser;
import org.apache.lucene.analysis.synonym.SynonymFilter;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.MultiFields;
import org.apache.lucene.search.spell.DirectSpellChecker;
import org.apache.lucene.search.spell.SuggestMode;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.BytesRef;
import org.elasticsearch.search.suggest.phrase.NoisyChannelSpellChecker.Result;
import org.elasticsearch.test.ESTestCase;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.StringReader;
import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Map;
import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.greaterThan;
public class NoisyChannelSpellCheckerTests extends ESTestCase {
private final BytesRef space = new BytesRef(" ");
private final BytesRef preTag = new BytesRef("<em>");
private final BytesRef postTag = new BytesRef("</em>");
public void testNgram() throws IOException {
RAMDirectory dir = new RAMDirectory();
Map<String, Analyzer> mapping = new HashMap<>();
mapping.put("body_ngram", new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
ShingleFilter tf = new ShingleFilter(t, 2, 3);
tf.setOutputUnigrams(false);
return new TokenStreamComponents(t, new LowerCaseFilter(tf));
}
});
mapping.put("body", new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
return new TokenStreamComponents(t, new LowerCaseFilter(t));
}
});
PerFieldAnalyzerWrapper wrapper = new PerFieldAnalyzerWrapper(new WhitespaceAnalyzer(), mapping);
IndexWriterConfig conf = new IndexWriterConfig(wrapper);
IndexWriter writer = new IndexWriter(dir, conf);
String[] strings = new String[]{
"Xorr the God-Jewel",
"Grog the God-Crusher",
"Xorn",
"Walter Newell",
"Wanda Maximoff",
"Captain America",
"American Ace",
"USA Hero",
"Wundarr the Aquarian",
"Will o' the Wisp",
"Xemnu the Titan",
"Fantastic Four",
"Quasar",
"Quasar II"
};
for (String line : strings) {
Document doc = new Document();
doc.add(new Field("body", line, TextField.TYPE_NOT_STORED));
doc.add(new Field("body_ngram", line, TextField.TYPE_NOT_STORED));
writer.addDocument(doc);
}
DirectoryReader ir = DirectoryReader.open(writer);
WordScorer wordScorer = new LaplaceScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.95d, new BytesRef(" "), 0.5f);
NoisyChannelSpellChecker suggester = new NoisyChannelSpellChecker();
DirectSpellChecker spellchecker = new DirectSpellChecker();
spellchecker.setMinQueryLength(1);
DirectCandidateGenerator generator = new DirectCandidateGenerator(spellchecker, "body", SuggestMode.SUGGEST_MORE_POPULAR, ir, 0.95, 5);
Result result = suggester.getCorrections(wrapper, new BytesRef("american ame"), generator, 1, 1, ir, "body", wordScorer, 1, 2);
Correction[] corrections = result.corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(space).utf8ToString(), equalTo("american ace"));
assertThat(corrections[0].join(space, preTag, postTag).utf8ToString(), equalTo("american <em>ace</em>"));
assertThat(result.cutoffScore, greaterThan(0d));
result = suggester.getCorrections(wrapper, new BytesRef("american ame"), generator, 1, 1, ir, "body", wordScorer, 0, 1);
corrections = result.corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(space).utf8ToString(), equalTo("american ame"));
assertThat(corrections[0].join(space, preTag, postTag).utf8ToString(), equalTo("american ame"));
assertThat(result.cutoffScore, equalTo(Double.MIN_VALUE));
suggester = new NoisyChannelSpellChecker(0.85);
wordScorer = new LaplaceScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.85d, new BytesRef(" "), 0.5f);
corrections = suggester.getCorrections(wrapper, new BytesRef("Xor the Got-Jewel"), generator, 0.5f, 4, ir, "body", wordScorer, 0, 2).corrections;
assertThat(corrections.length, equalTo(4));
assertThat(corrections[0].join(space).utf8ToString(), equalTo("xorr the god jewel"));
assertThat(corrections[1].join(space).utf8ToString(), equalTo("xor the god jewel"));
assertThat(corrections[2].join(space).utf8ToString(), equalTo("xorn the god jewel"));
assertThat(corrections[3].join(space).utf8ToString(), equalTo("xorr the got jewel"));
assertThat(corrections[0].join(space, preTag, postTag).utf8ToString(), equalTo("<em>xorr</em> the <em>god</em> jewel"));
assertThat(corrections[1].join(space, preTag, postTag).utf8ToString(), equalTo("xor the <em>god</em> jewel"));
assertThat(corrections[2].join(space, preTag, postTag).utf8ToString(), equalTo("<em>xorn</em> the <em>god</em> jewel"));
assertThat(corrections[3].join(space, preTag, postTag).utf8ToString(), equalTo("<em>xorr</em> the got jewel"));
corrections = suggester.getCorrections(wrapper, new BytesRef("Xor the Got-Jewel"), generator, 0.5f, 4, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections.length, equalTo(4));
assertThat(corrections[0].join(space).utf8ToString(), equalTo("xorr the god jewel"));
assertThat(corrections[1].join(space).utf8ToString(), equalTo("xor the god jewel"));
assertThat(corrections[2].join(space).utf8ToString(), equalTo("xorn the god jewel"));
assertThat(corrections[3].join(space).utf8ToString(), equalTo("xorr the got jewel"));
// Test some of the highlighting corner cases
suggester = new NoisyChannelSpellChecker(0.85);
wordScorer = new LaplaceScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.85d, new BytesRef(" "), 0.5f);
corrections = suggester.getCorrections(wrapper, new BytesRef("Xor teh Got-Jewel"), generator, 4f, 4, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections.length, equalTo(4));
assertThat(corrections[0].join(space).utf8ToString(), equalTo("xorr the god jewel"));
assertThat(corrections[1].join(space).utf8ToString(), equalTo("xor the god jewel"));
assertThat(corrections[2].join(space).utf8ToString(), equalTo("xorn the god jewel"));
assertThat(corrections[3].join(space).utf8ToString(), equalTo("xor teh god jewel"));
assertThat(corrections[0].join(space, preTag, postTag).utf8ToString(), equalTo("<em>xorr the god</em> jewel"));
assertThat(corrections[1].join(space, preTag, postTag).utf8ToString(), equalTo("xor <em>the god</em> jewel"));
assertThat(corrections[2].join(space, preTag, postTag).utf8ToString(), equalTo("<em>xorn the god</em> jewel"));
assertThat(corrections[3].join(space, preTag, postTag).utf8ToString(), equalTo("xor teh <em>god</em> jewel"));
// test synonyms
Analyzer analyzer = new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
TokenFilter filter = new LowerCaseFilter(t);
try {
SolrSynonymParser parser = new SolrSynonymParser(true, false, new WhitespaceAnalyzer());
parser.parse(new StringReader("usa => usa, america, american"));
filter = new SynonymFilter(filter, parser.build(), true);
} catch (Exception e) {
throw new RuntimeException(e);
}
return new TokenStreamComponents(t, filter);
}
};
spellchecker.setAccuracy(0.0f);
spellchecker.setMinPrefix(1);
spellchecker.setMinQueryLength(1);
suggester = new NoisyChannelSpellChecker(0.85);
wordScorer = new LaplaceScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.85d, new BytesRef(" "), 0.5f);
corrections = suggester.getCorrections(analyzer, new BytesRef("captian usa"), generator, 2, 4, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections[0].join(space).utf8ToString(), equalTo("captain america"));
assertThat(corrections[0].join(space, preTag, postTag).utf8ToString(), equalTo("<em>captain america</em>"));
generator = new DirectCandidateGenerator(spellchecker, "body", SuggestMode.SUGGEST_MORE_POPULAR, ir, 0.85, 10, null, analyzer, MultiFields.getTerms(ir, "body"));
corrections = suggester.getCorrections(analyzer, new BytesRef("captian usw"), generator, 2, 4, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("captain america"));
assertThat(corrections[0].join(space, preTag, postTag).utf8ToString(), equalTo("<em>captain america</em>"));
// Make sure that user supplied text is not marked as highlighted in the presence of a synonym filter
generator = new DirectCandidateGenerator(spellchecker, "body", SuggestMode.SUGGEST_MORE_POPULAR, ir, 0.85, 10, null, analyzer, MultiFields.getTerms(ir, "body"));
corrections = suggester.getCorrections(analyzer, new BytesRef("captain usw"), generator, 2, 4, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("captain america"));
assertThat(corrections[0].join(space, preTag, postTag).utf8ToString(), equalTo("captain <em>america</em>"));
}
public void testMultiGenerator() throws IOException {
RAMDirectory dir = new RAMDirectory();
Map<String, Analyzer> mapping = new HashMap<>();
mapping.put("body_ngram", new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
ShingleFilter tf = new ShingleFilter(t, 2, 3);
tf.setOutputUnigrams(false);
return new TokenStreamComponents(t, new LowerCaseFilter(tf));
}
});
mapping.put("body", new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
return new TokenStreamComponents(t, new LowerCaseFilter(t));
}
});
mapping.put("body_reverse", new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
return new TokenStreamComponents(t, new ReverseStringFilter(new LowerCaseFilter(t)));
}
});
PerFieldAnalyzerWrapper wrapper = new PerFieldAnalyzerWrapper(new WhitespaceAnalyzer(), mapping);
IndexWriterConfig conf = new IndexWriterConfig(wrapper);
IndexWriter writer = new IndexWriter(dir, conf);
String[] strings = new String[]{
"Xorr the God-Jewel",
"Grog the God-Crusher",
"Xorn",
"Walter Newell",
"Wanda Maximoff",
"Captain America",
"American Ace",
"Wundarr the Aquarian",
"Will o' the Wisp",
"Xemnu the Titan",
"Fantastic Four",
"Quasar",
"Quasar II"
};
for (String line : strings) {
Document doc = new Document();
doc.add(new Field("body", line, TextField.TYPE_NOT_STORED));
doc.add(new Field("body_reverse", line, TextField.TYPE_NOT_STORED));
doc.add(new Field("body_ngram", line, TextField.TYPE_NOT_STORED));
writer.addDocument(doc);
}
DirectoryReader ir = DirectoryReader.open(writer);
LaplaceScorer wordScorer = new LaplaceScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.95d, new BytesRef(" "), 0.5f);
NoisyChannelSpellChecker suggester = new NoisyChannelSpellChecker();
DirectSpellChecker spellchecker = new DirectSpellChecker();
spellchecker.setMinQueryLength(1);
DirectCandidateGenerator forward = new DirectCandidateGenerator(spellchecker, "body", SuggestMode.SUGGEST_ALWAYS, ir, 0.95, 10);
DirectCandidateGenerator reverse = new DirectCandidateGenerator(spellchecker, "body_reverse", SuggestMode.SUGGEST_ALWAYS, ir, 0.95, 10, wrapper, wrapper, MultiFields.getTerms(ir, "body_reverse"));
CandidateGenerator generator = new MultiCandidateGeneratorWrapper(10, forward, reverse);
Correction[] corrections = suggester.getCorrections(wrapper, new BytesRef("american cae"), generator, 1, 1, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("american ace"));
generator = new MultiCandidateGeneratorWrapper(5, forward, reverse);
corrections = suggester.getCorrections(wrapper, new BytesRef("american ame"), generator, 1, 1, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("american ace"));
corrections = suggester.getCorrections(wrapper, new BytesRef("american cae"), forward, 1, 1, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections.length, equalTo(0)); // only use forward with constant prefix
corrections = suggester.getCorrections(wrapper, new BytesRef("america cae"), generator, 2, 1, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("american ace"));
corrections = suggester.getCorrections(wrapper, new BytesRef("Zorr the Got-Jewel"), generator, 0.5f, 4, ir, "body", wordScorer, 0, 2).corrections;
assertThat(corrections.length, equalTo(4));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the god jewel"));
assertThat(corrections[1].join(new BytesRef(" ")).utf8ToString(), equalTo("zorr the god jewel"));
assertThat(corrections[2].join(new BytesRef(" ")).utf8ToString(), equalTo("four the god jewel"));
corrections = suggester.getCorrections(wrapper, new BytesRef("Zorr the Got-Jewel"), generator, 0.5f, 1, ir, "body", wordScorer, 1.5f, 2).corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the god jewel"));
corrections = suggester.getCorrections(wrapper, new BytesRef("Xor the Got-Jewel"), generator, 0.5f, 1, ir, "body", wordScorer, 1.5f, 2).corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the god jewel"));
// Test a special case where one of the suggest term is unchanged by the postFilter, 'II' here is unchanged by the reverse analyzer.
corrections = suggester.getCorrections(wrapper, new BytesRef("Quazar II"), generator, 1, 1, ir, "body", wordScorer, 1, 2).corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("quasar ii"));
}
public void testTrigram() throws IOException {
RAMDirectory dir = new RAMDirectory();
Map<String, Analyzer> mapping = new HashMap<>();
mapping.put("body_ngram", new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
ShingleFilter tf = new ShingleFilter(t, 2, 3);
tf.setOutputUnigrams(false);
return new TokenStreamComponents(t, new LowerCaseFilter(tf));
}
});
mapping.put("body", new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
return new TokenStreamComponents(t, new LowerCaseFilter(t));
}
});
PerFieldAnalyzerWrapper wrapper = new PerFieldAnalyzerWrapper(new WhitespaceAnalyzer(), mapping);
IndexWriterConfig conf = new IndexWriterConfig(wrapper);
IndexWriter writer = new IndexWriter(dir, conf);
String[] strings = new String[]{
"Xorr the God-Jewel",
"Grog the God-Crusher",
"Xorn",
"Walter Newell",
"Wanda Maximoff",
"Captain America",
"American Ace",
"USA Hero",
"Wundarr the Aquarian",
"Will o' the Wisp",
"Xemnu the Titan",
"Fantastic Four",
"Quasar",
"Quasar II"
};
for (String line : strings) {
Document doc = new Document();
doc.add(new Field("body", line, TextField.TYPE_NOT_STORED));
doc.add(new Field("body_ngram", line, TextField.TYPE_NOT_STORED));
writer.addDocument(doc);
}
DirectoryReader ir = DirectoryReader.open(writer);
WordScorer wordScorer = new LinearInterpolatingScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.85d, new BytesRef(" "), 0.5, 0.4, 0.1);
NoisyChannelSpellChecker suggester = new NoisyChannelSpellChecker();
DirectSpellChecker spellchecker = new DirectSpellChecker();
spellchecker.setMinQueryLength(1);
DirectCandidateGenerator generator = new DirectCandidateGenerator(spellchecker, "body", SuggestMode.SUGGEST_MORE_POPULAR, ir, 0.95, 5);
Correction[] corrections = suggester.getCorrections(wrapper, new BytesRef("american ame"), generator, 1, 1, ir, "body", wordScorer, 1, 3).corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("american ace"));
corrections = suggester.getCorrections(wrapper, new BytesRef("american ame"), generator, 1, 1, ir, "body", wordScorer, 1, 1).corrections;
assertThat(corrections.length, equalTo(0));
// assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("american ape"));
wordScorer = new LinearInterpolatingScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.85d, new BytesRef(" "), 0.5, 0.4, 0.1);
corrections = suggester.getCorrections(wrapper, new BytesRef("Xor the Got-Jewel"), generator, 0.5f, 4, ir, "body", wordScorer, 0, 3).corrections;
assertThat(corrections.length, equalTo(4));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the god jewel"));
assertThat(corrections[1].join(new BytesRef(" ")).utf8ToString(), equalTo("xor the god jewel"));
assertThat(corrections[2].join(new BytesRef(" ")).utf8ToString(), equalTo("xorn the god jewel"));
assertThat(corrections[3].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the got jewel"));
corrections = suggester.getCorrections(wrapper, new BytesRef("Xor the Got-Jewel"), generator, 0.5f, 4, ir, "body", wordScorer, 1, 3).corrections;
assertThat(corrections.length, equalTo(4));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the god jewel"));
assertThat(corrections[1].join(new BytesRef(" ")).utf8ToString(), equalTo("xor the god jewel"));
assertThat(corrections[2].join(new BytesRef(" ")).utf8ToString(), equalTo("xorn the god jewel"));
assertThat(corrections[3].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the got jewel"));
corrections = suggester.getCorrections(wrapper, new BytesRef("Xor the Got-Jewel"), generator, 0.5f, 1, ir, "body", wordScorer, 100, 3).corrections;
assertThat(corrections.length, equalTo(1));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the god jewel"));
// test synonyms
Analyzer analyzer = new Analyzer() {
@Override
protected TokenStreamComponents createComponents(String fieldName) {
Tokenizer t = new StandardTokenizer();
TokenFilter filter = new LowerCaseFilter(t);
try {
SolrSynonymParser parser = new SolrSynonymParser(true, false, new WhitespaceAnalyzer());
parser.parse(new StringReader("usa => usa, america, american"));
filter = new SynonymFilter(filter, parser.build(), true);
} catch (Exception e) {
throw new RuntimeException(e);
}
return new TokenStreamComponents(t, filter);
}
};
spellchecker.setAccuracy(0.0f);
spellchecker.setMinPrefix(1);
spellchecker.setMinQueryLength(1);
suggester = new NoisyChannelSpellChecker(0.95);
wordScorer = new LinearInterpolatingScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.95d, new BytesRef(" "), 0.5, 0.4, 0.1);
corrections = suggester.getCorrections(analyzer, new BytesRef("captian usa"), generator, 2, 4, ir, "body", wordScorer, 1, 3).corrections;
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("captain america"));
generator = new DirectCandidateGenerator(spellchecker, "body", SuggestMode.SUGGEST_MORE_POPULAR, ir, 0.95, 10, null, analyzer, MultiFields.getTerms(ir, "body"));
corrections = suggester.getCorrections(analyzer, new BytesRef("captian usw"), generator, 2, 4, ir, "body", wordScorer, 1, 3).corrections;
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("captain america"));
wordScorer = new StupidBackoffScorer(ir, MultiFields.getTerms(ir, "body_ngram"), "body_ngram", 0.85d, new BytesRef(" "), 0.4);
corrections = suggester.getCorrections(wrapper, new BytesRef("Xor the Got-Jewel"), generator, 0.5f, 2, ir, "body", wordScorer, 0, 3).corrections;
assertThat(corrections.length, equalTo(2));
assertThat(corrections[0].join(new BytesRef(" ")).utf8ToString(), equalTo("xorr the god jewel"));
assertThat(corrections[1].join(new BytesRef(" ")).utf8ToString(), equalTo("xor the god jewel"));
}
}