Query DSL: Support fuzzy query, closes #213.

modules/elasticsearch/src/main/java/org/elasticsearch/index/query/xcontent/FuzzyLikeThisQueryParser.java

@@ -84,6 +84,10 @@ public class FuzzyLikeThisQueryParser extends AbstractIndexComponent implements
                     boost = parser.floatValue();
                 } else if ("ignore_tf".equals(currentFieldName) || "ignoreTF".equals(currentFieldName)) {
                     ignoreTF = parser.booleanValue();
+                } else if ("min_similarity".equals(currentFieldName) || "minSimilarity".equals(currentFieldName)) {
+                    minSimilarity = parser.floatValue();
+                } else if ("prefix_length".equals(currentFieldName) || "prefixLength".equals(currentFieldName)) {
+                    prefixLength = parser.intValue();
                 }
             } else if (token == XContentParser.Token.START_ARRAY) {
                 if ("fields".equals(currentFieldName)) {

modules/elasticsearch/src/main/java/org/elasticsearch/index/query/xcontent/FuzzyQueryBuilder.java

@@ -0,0 +1,93 @@
+/*
+ * Licensed to Elastic Search and Shay Banon under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. Elastic Search 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.
+ */
+
+package org.elasticsearch.index.query.xcontent;
+
+import org.elasticsearch.util.xcontent.builder.XContentBuilder;
+
+import java.io.IOException;
+
+/**
+ * A Query that does fuzzy matching for a specific value.
+ *
+ * @author kimchy (shay.banon)
+ */
+public class FuzzyQueryBuilder extends BaseQueryBuilder {
+
+    private final String name;
+
+    private final String value;
+
+    private float boost = -1;
+
+    private Float minSimilarity;
+
+    private Integer prefixLength;
+
+    /**
+     * Constructs a new term query.
+     *
+     * @param name  The name of the field
+     * @param value The value of the term
+     */
+    public FuzzyQueryBuilder(String name, String value) {
+        this.name = name;
+        this.value = value;
+    }
+
+    /**
+     * Sets the boost for this query.  Documents matching this query will (in addition to the normal
+     * weightings) have their score multiplied by the boost provided.
+     */
+    public FuzzyQueryBuilder boost(float boost) {
+        this.boost = boost;
+        return this;
+    }
+
+    public FuzzyQueryBuilder minSimilarity(float defaultMinSimilarity) {
+        this.minSimilarity = defaultMinSimilarity;
+        return this;
+    }
+
+    public FuzzyQueryBuilder prefixLength(int prefixLength) {
+        this.prefixLength = prefixLength;
+        return this;
+    }
+
+    @Override public void doXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject(FuzzyQueryParser.NAME);
+        if (boost == -1 && minSimilarity == null && prefixLength == null) {
+            builder.field(name, value);
+        } else {
+            builder.startObject(name);
+            builder.field("value", value);
+            if (boost != -1) {
+                builder.field("boost", boost);
+            }
+            if (minSimilarity != null) {
+                builder.field("min_similarity", minSimilarity);
+            }
+            if (prefixLength != null) {
+                builder.field("prefix_length", prefixLength);
+            }
+            builder.endObject();
+        }
+        builder.endObject();
+    }
+}

modules/elasticsearch/src/main/java/org/elasticsearch/index/query/xcontent/FuzzyQueryParser.java

@@ -0,0 +1,101 @@
+/*
+ * Licensed to Elastic Search and Shay Banon under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. Elastic Search 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.
+ */
+
+package org.elasticsearch.index.query.xcontent;
+
+import org.apache.lucene.index.Term;
+import org.apache.lucene.search.FuzzyQuery;
+import org.apache.lucene.search.Query;
+import org.elasticsearch.index.AbstractIndexComponent;
+import org.elasticsearch.index.Index;
+import org.elasticsearch.index.mapper.MapperService;
+import org.elasticsearch.index.query.QueryParsingException;
+import org.elasticsearch.index.settings.IndexSettings;
+import org.elasticsearch.util.settings.Settings;
+import org.elasticsearch.util.xcontent.XContentParser;
+
+import java.io.IOException;
+
+import static org.elasticsearch.index.query.support.QueryParsers.*;
+
+/**
+ * @author kimchy (shay.banon)
+ */
+public class FuzzyQueryParser extends AbstractIndexComponent implements XContentQueryParser {
+
+    public static final String NAME = "fuzzy";
+
+    public FuzzyQueryParser(Index index, @IndexSettings Settings indexSettings) {
+        super(index, indexSettings);
+    }
+
+    @Override public String[] names() {
+        return new String[]{NAME};
+    }
+
+    @Override public Query parse(QueryParseContext parseContext) throws IOException, QueryParsingException {
+        XContentParser parser = parseContext.parser();
+
+        XContentParser.Token token = parser.nextToken();
+        assert token == XContentParser.Token.FIELD_NAME;
+        String fieldName = parser.currentName();
+
+        String value = null;
+        float boost = 1.0f;
+        float minSimilarity = FuzzyQuery.defaultMinSimilarity;
+        int prefixLength = FuzzyQuery.defaultPrefixLength;
+        token = parser.nextToken();
+        if (token == XContentParser.Token.START_OBJECT) {
+            String currentFieldName = null;
+            while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
+                if (token == XContentParser.Token.FIELD_NAME) {
+                    currentFieldName = parser.currentName();
+                } else {
+                    if ("term".equals(currentFieldName)) {
+                        value = parser.text();
+                    } else if ("value".equals(currentFieldName)) {
+                        value = parser.text();
+                    } else if ("boost".equals(currentFieldName)) {
+                        boost = parser.floatValue();
+                    } else if ("min_similarity".equals(currentFieldName) || "minSimilarity".equals(currentFieldName)) {
+                        minSimilarity = parser.floatValue();
+                    } else if ("prefix_length".equals(currentFieldName) || "prefixLength".equals(currentFieldName)) {
+                        prefixLength = parser.intValue();
+                    }
+                }
+            }
+            parser.nextToken();
+        } else {
+            value = parser.text();
+            // move to the next token
+            parser.nextToken();
+        }
+
+        if (value == null) {
+            throw new QueryParsingException(index, "No value specified for fuzzy query");
+        }
+
+        MapperService.SmartNameFieldMappers smartNameFieldMappers = parseContext.smartFieldMappers(fieldName);
+
+        FuzzyQuery fuzzyQuery = new FuzzyQuery(new Term(fieldName, value), minSimilarity, prefixLength);
+        fuzzyQuery.setBoost(boost);
+
+        return wrapSmartNameQuery(fuzzyQuery, smartNameFieldMappers, parseContext);
+    }
+}

modules/elasticsearch/src/main/java/org/elasticsearch/index/query/xcontent/QueryBuilders.java

@@ -82,6 +82,16 @@ public abstract class QueryBuilders {
         return new TermQueryBuilder(name, value);
     }
 
+    /**
+     * A Query that matches documents using fuzzy query.
+     *
+     * @param name  The name of the field
+     * @param value The value of the term
+     */
+    public static FuzzyQueryBuilder fuzzyQuery(String name, String value) {
+        return new FuzzyQueryBuilder(name, value);
+    }
+
     /**
      * A Query that matches documents containing a term.
      *

modules/elasticsearch/src/main/java/org/elasticsearch/index/query/xcontent/XContentQueryParserRegistry.java

@@ -52,6 +52,7 @@ public class XContentQueryParserRegistry {
         add(queryParsersMap, new QueryStringQueryParser(index, indexSettings, analysisService));
         add(queryParsersMap, new BoolQueryParser(index, indexSettings));
         add(queryParsersMap, new TermQueryParser(index, indexSettings));
+        add(queryParsersMap, new FuzzyQueryParser(index, indexSettings));
         add(queryParsersMap, new FieldQueryParser(index, indexSettings, analysisService));
         add(queryParsersMap, new RangeQueryParser(index, indexSettings));
         add(queryParsersMap, new PrefixQueryParser(index, indexSettings));

modules/elasticsearch/src/test/java/org/elasticsearch/index/query/xcontent/SimpleIndexQueryParserTests.java

@@ -220,6 +220,46 @@ public class SimpleIndexQueryParserTests {
         assertThat(fieldQuery.includesMin(), equalTo(true));
     }
 
+    @Test public void testFuzzyQueryBuilder() throws IOException {
+        IndexQueryParser queryParser = newQueryParser();
+        Query parsedQuery = queryParser.parse(fuzzyQuery("name.first", "sh").buildAsBytes());
+        assertThat(parsedQuery, instanceOf(FuzzyQuery.class));
+        FuzzyQuery fuzzyQuery = (FuzzyQuery) parsedQuery;
+        assertThat(fuzzyQuery.getTerm(), equalTo(new Term("name.first", "sh")));
+    }
+
+    @Test public void testFuzzyQuery() throws IOException {
+        IndexQueryParser queryParser = newQueryParser();
+        String query = copyToStringFromClasspath("/org/elasticsearch/index/query/xcontent/fuzzy.json");
+        Query parsedQuery = queryParser.parse(query);
+        assertThat(parsedQuery, instanceOf(FuzzyQuery.class));
+        FuzzyQuery fuzzyQuery = (FuzzyQuery) parsedQuery;
+        assertThat(fuzzyQuery.getTerm(), equalTo(new Term("name.first", "sh")));
+    }
+
+    @Test public void testFuzzyQueryWithFieldsBuilder() throws IOException {
+        IndexQueryParser queryParser = newQueryParser();
+        Query parsedQuery = queryParser.parse(fuzzyQuery("name.first", "sh").minSimilarity(0.1f).prefixLength(1).boost(2.0f).buildAsBytes());
+        assertThat(parsedQuery, instanceOf(FuzzyQuery.class));
+        FuzzyQuery fuzzyQuery = (FuzzyQuery) parsedQuery;
+        assertThat(fuzzyQuery.getTerm(), equalTo(new Term("name.first", "sh")));
+        assertThat(fuzzyQuery.getMinSimilarity(), equalTo(0.1f));
+        assertThat(fuzzyQuery.getPrefixLength(), equalTo(1));
+        assertThat(fuzzyQuery.getBoost(), equalTo(2.0f));
+    }
+
+    @Test public void testFuzzyQueryWithFields() throws IOException {
+        IndexQueryParser queryParser = newQueryParser();
+        String query = copyToStringFromClasspath("/org/elasticsearch/index/query/xcontent/fuzzy-with-fields.json");
+        Query parsedQuery = queryParser.parse(query);
+        assertThat(parsedQuery, instanceOf(FuzzyQuery.class));
+        FuzzyQuery fuzzyQuery = (FuzzyQuery) parsedQuery;
+        assertThat(fuzzyQuery.getTerm(), equalTo(new Term("name.first", "sh")));
+        assertThat(fuzzyQuery.getMinSimilarity(), equalTo(0.1f));
+        assertThat(fuzzyQuery.getPrefixLength(), equalTo(1));
+        assertThat(fuzzyQuery.getBoost(), equalTo(2.0f));
+    }
+
     @Test public void testFieldQueryBuilder1() throws IOException {
         IndexQueryParser queryParser = newQueryParser();
         Query parsedQuery = queryParser.parse(fieldQuery("age", 34).buildAsBytes());

modules/elasticsearch/src/test/java/org/elasticsearch/index/query/xcontent/fuzzy-with-fields.json

@@ -0,0 +1,10 @@
+{
+    "fuzzy" : {
+        "name.first" :  {
+            "value" : "sh",
+            "min_similarity" : 0.1,
+            "prefix_length" : 1,
+            "boost" : 2.0
+        }
+    }
+}

modules/elasticsearch/src/test/java/org/elasticsearch/index/query/xcontent/fuzzy.json

@@ -0,0 +1,3 @@
+{
+    "fuzzy" : { "name.first" : "sh" }
+}