Add fuzzy intervals source (#49762)

This intervals source will return terms that are similar to an input term, up to
an edit distance defined by fuzziness, similar to FuzzyQuery.

Closes #49595

docs/reference/query-dsl/intervals-query.asciidoc

@@ -73,6 +73,7 @@ Valid rules include:
 * <<intervals-match,`match`>>
 * <<intervals-prefix,`prefix`>>
 * <<intervals-wildcard,`wildcard`>>
+* <<intervals-fuzzy,`fuzzy`>>
 * <<intervals-all_of,`all_of`>>
 * <<intervals-any_of,`any_of`>>
 --
@@ -97,7 +98,7 @@ set to `0`, the terms must appear next to each other.
 --
 
 `ordered`::
-(Optional, boolean) 
+(Optional, boolean)
 If `true`, matching terms must appear in their specified order. Defaults to
 `false`.
 
@@ -177,6 +178,42 @@ The `pattern` is normalized using the search analyzer from this field, unless
 `analyzer` is specified separately.
 --
 
+[[intervals-fuzzy]]
+==== `fuzzy` rule parameters
+
+The `fuzzy` rule matches terms that are similar to the provided term, within an
+edit distance defined by <<fuzziness>>.  If the fuzzy expansion matches more than
+128 terms, {es} returns an error.
+
+`term`::
+(Required, string) The term to match
+
+`prefix_length`::
+(Optional, string) Number of beginning characters left unchanged when creating
+expansions. Defaults to `0`.
+
+`transpositions`::
+(Optional, boolean) Indicates whether edits include transpositions of two
+adjacent characters (ab → ba). Defaults to `true`.
+
+`fuzziness`::
+(Optional, string) Maximum edit distance allowed for matching. See <<fuzziness>>
+for valid values and more information.  Defaults to `auto`.
+
+`analyzer`::
+(Optional, string) <<analysis, analyzer>> used to normalize the `term`.
+Defaults to the top-level `<field>` 's analyzer.
+
+`use_field`::
++
+--
+(Optional, string) If specified, match intervals from this field rather than the
+top-level `<field>`.
+
+The `term` is normalized using the search analyzer from this field, unless
+`analyzer` is specified separately.
+--
+
 [[intervals-all_of]]
 ==== `all_of` rule parameters
 

rest-api-spec/src/main/resources/rest-api-spec/test/search/230_interval_query.yml

@@ -390,8 +390,8 @@ setup:
 ---
 "Test prefix":
   - skip:
-      version: " - 8.0.0"
-      reason: "TODO: change to 7.3 in backport"
+      version: " - 7.2.99"
+      reason: "Implemented in 7.3"
   - do:
       search:
         index: test
@@ -410,8 +410,8 @@ setup:
 ---
 "Test wildcard":
   - skip:
-      version: " - 8.0.0"
-      reason: "TODO: change to 7.3 in backport"
+      version: " - 7.2.99"
+      reason: "Implemented in 7.3"
   - do:
       search:
         index: test
@@ -427,3 +427,24 @@ setup:
                         pattern: out?ide
   - match: { hits.total.value: 3 }
 
+---
+"Test fuzzy match":
+  - skip:
+      version: " - 7.5.99"
+      reason: "Implemented in 7.6"
+  - do:
+      search:
+        index: test
+        body:
+          query:
+            intervals:
+              text:
+                all_of:
+                  intervals:
+                    - fuzzy:
+                        query: cald
+                    - prefix:
+                        prefix: out
+  - match: { hits.total.value: 3 }
+
+

server/src/main/java/org/apache/lucene/queries/XIntervals.java

@@ -67,6 +67,10 @@ public static IntervalsSource prefix(BytesRef prefix) {
         return new MultiTermIntervalsSource(ca, 128, prefix.utf8ToString());
     }
 
+    public static IntervalsSource multiterm(CompiledAutomaton ca, String label) {
+        return new MultiTermIntervalsSource(ca, 128, label);
+    }
+
     static class MultiTermIntervalsSource extends IntervalsSource {
 
         private final CompiledAutomaton automaton;

server/src/main/java/org/elasticsearch/index/query/IntervalsSourceProvider.java

@@ -20,20 +20,25 @@
 package org.elasticsearch.index.query;
 
 import org.apache.lucene.index.IndexOptions;
+import org.apache.lucene.index.Term;
 import org.apache.lucene.queries.XIntervals;
 import org.apache.lucene.queries.intervals.FilteredIntervalsSource;
 import org.apache.lucene.queries.intervals.IntervalIterator;
 import org.apache.lucene.queries.intervals.Intervals;
 import org.apache.lucene.queries.intervals.IntervalsSource;
+import org.apache.lucene.search.FuzzyQuery;
 import org.apache.lucene.util.BytesRef;
+import org.apache.lucene.util.automaton.CompiledAutomaton;
 import org.elasticsearch.Version;
 import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.ParsingException;
 import org.elasticsearch.common.io.stream.NamedWriteable;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
+import org.elasticsearch.common.unit.Fuzziness;
 import org.elasticsearch.common.xcontent.ConstructingObjectParser;
+import org.elasticsearch.common.xcontent.ObjectParser;
 import org.elasticsearch.common.xcontent.ToXContentFragment;
 import org.elasticsearch.common.xcontent.ToXContentObject;
 import org.elasticsearch.common.xcontent.XContentBuilder;
@@ -85,6 +90,8 @@ public static IntervalsSourceProvider fromXContent(XContentParser parser) throws
                 return Prefix.fromXContent(parser);
             case "wildcard":
                 return Wildcard.fromXContent(parser);
+            case "fuzzy":
+                return Fuzzy.fromXContent(parser);
         }
         throw new ParsingException(parser.getTokenLocation(),
             "Unknown interval type [" + parser.currentName() + "], expecting one of [match, any_of, all_of, prefix, wildcard]");
@@ -691,6 +698,148 @@ String getUseField() {
         }
     }
 
+    public static class Fuzzy extends IntervalsSourceProvider {
+
+        public static final String NAME = "fuzzy";
+
+        private final String term;
+        private final int prefixLength;
+        private final boolean transpositions;
+        private final Fuzziness fuzziness;
+        private final String analyzer;
+        private final String useField;
+
+        public Fuzzy(String term, int prefixLength, boolean transpositions, Fuzziness fuzziness, String analyzer, String useField) {
+            this.term = term;
+            this.prefixLength = prefixLength;
+            this.transpositions = transpositions;
+            this.fuzziness = fuzziness;
+            this.analyzer = analyzer;
+            this.useField = useField;
+        }
+
+        public Fuzzy(StreamInput in) throws IOException {
+            this.term = in.readString();
+            this.prefixLength = in.readVInt();
+            this.transpositions = in.readBoolean();
+            this.fuzziness = new Fuzziness(in);
+            this.analyzer = in.readOptionalString();
+            this.useField = in.readOptionalString();
+        }
+
+        @Override
+        public IntervalsSource getSource(QueryShardContext context, MappedFieldType fieldType) {
+            NamedAnalyzer analyzer = fieldType.searchAnalyzer();
+            if (this.analyzer != null) {
+                analyzer = context.getMapperService().getIndexAnalyzers().get(this.analyzer);
+            }
+            IntervalsSource source;
+            if (useField != null) {
+                fieldType = context.fieldMapper(useField);
+                assert fieldType != null;
+                checkPositions(fieldType);
+                if (this.analyzer == null) {
+                    analyzer = fieldType.searchAnalyzer();
+                }
+            }
+            checkPositions(fieldType);
+            BytesRef normalizedTerm = analyzer.normalize(fieldType.name(), term);
+            FuzzyQuery fq = new FuzzyQuery(new Term(fieldType.name(), normalizedTerm),
+                fuzziness.asDistance(term), prefixLength, 128, transpositions);
+            CompiledAutomaton ca = new CompiledAutomaton(fq.toAutomaton());
+            source = XIntervals.multiterm(ca, term);
+            if (useField != null) {
+                source = Intervals.fixField(useField, source);
+            }
+            return source;
+        }
+
+        private void checkPositions(MappedFieldType type) {
+            if (type.indexOptions().compareTo(IndexOptions.DOCS_AND_FREQS_AND_POSITIONS) < 0) {
+                throw new IllegalArgumentException("Cannot create intervals over field [" + type.name() + "] with no positions indexed");
+            }
+        }
+
+        @Override
+        public void extractFields(Set<String> fields) {
+            if (useField != null) {
+                fields.add(useField);
+            }
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o == null || getClass() != o.getClass()) return false;
+            Fuzzy fuzzy = (Fuzzy) o;
+            return prefixLength == fuzzy.prefixLength &&
+                transpositions == fuzzy.transpositions &&
+                Objects.equals(term, fuzzy.term) &&
+                Objects.equals(fuzziness, fuzzy.fuzziness) &&
+                Objects.equals(analyzer, fuzzy.analyzer) &&
+                Objects.equals(useField, fuzzy.useField);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(term, prefixLength, transpositions, fuzziness, analyzer, useField);
+        }
+
+        @Override
+        public String getWriteableName() {
+            return NAME;
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            out.writeString(term);
+            out.writeVInt(prefixLength);
+            out.writeBoolean(transpositions);
+            fuzziness.writeTo(out);
+            out.writeOptionalString(analyzer);
+            out.writeOptionalString(useField);
+        }
+
+        @Override
+        public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+            builder.startObject(NAME);
+            builder.field("term", term);
+            builder.field("prefix_length", prefixLength);
+            builder.field("transpositions", transpositions);
+            fuzziness.toXContent(builder, params);
+            if (analyzer != null) {
+                builder.field("analyzer", analyzer);
+            }
+            if (useField != null) {
+                builder.field("use_field", useField);
+            }
+            builder.endObject();
+            return builder;
+        }
+
+        private static final ConstructingObjectParser<Fuzzy, Void> PARSER = new ConstructingObjectParser<>(NAME, args -> {
+            String term = (String) args[0];
+            int prefixLength = (args[1] == null) ? FuzzyQueryBuilder.DEFAULT_PREFIX_LENGTH : (int) args[1];
+            boolean transpositions = (args[2] == null) ? FuzzyQueryBuilder.DEFAULT_TRANSPOSITIONS : (boolean) args[2];
+            Fuzziness fuzziness = (args[3] == null) ? FuzzyQueryBuilder.DEFAULT_FUZZINESS : (Fuzziness) args[3];
+            String analyzer = (String) args[4];
+            String useField = (String) args[5];
+            return new Fuzzy(term, prefixLength, transpositions, fuzziness, analyzer, useField);
+        });
+        static {
+            PARSER.declareString(constructorArg(), new ParseField("term"));
+            PARSER.declareInt(optionalConstructorArg(), new ParseField("prefix_length"));
+            PARSER.declareBoolean(optionalConstructorArg(), new ParseField("transpositions"));
+            PARSER.declareField(optionalConstructorArg(), (p, c) -> Fuzziness.parse(p), Fuzziness.FIELD, ObjectParser.ValueType.VALUE);
+            PARSER.declareString(optionalConstructorArg(), new ParseField("analyzer"));
+            PARSER.declareString(optionalConstructorArg(), new ParseField("use_field"));
+        }
+
+        public static Fuzzy fromXContent(XContentParser parser) throws IOException {
+            return PARSER.parse(parser, null);
+        }
+    }
+
     static class ScriptFilterSource extends FilteredIntervalsSource {
 
         final IntervalFilterScript script;

server/src/main/java/org/elasticsearch/search/SearchModule.java

@@ -861,6 +861,8 @@ private void registerIntervalsSourceProviders() {
             IntervalsSourceProvider.Prefix.NAME, IntervalsSourceProvider.Prefix::new));
         namedWriteables.add(new NamedWriteableRegistry.Entry(IntervalsSourceProvider.class,
             IntervalsSourceProvider.Wildcard.NAME, IntervalsSourceProvider.Wildcard::new));
+        namedWriteables.add(new NamedWriteableRegistry.Entry(IntervalsSourceProvider.class,
+            IntervalsSourceProvider.Fuzzy.NAME, IntervalsSourceProvider.Fuzzy::new));
     }
 
     private void registerQuery(QuerySpec<?> spec) {

server/src/test/java/org/elasticsearch/index/query/IntervalQueryBuilderTests.java

@@ -19,17 +19,22 @@
 
 package org.elasticsearch.index.query;
 
+import org.apache.lucene.index.Term;
 import org.apache.lucene.queries.XIntervals;
 import org.apache.lucene.queries.intervals.IntervalQuery;
 import org.apache.lucene.queries.intervals.Intervals;
+import org.apache.lucene.queries.intervals.IntervalsSource;
 import org.apache.lucene.search.BoostQuery;
+import org.apache.lucene.search.FuzzyQuery;
 import org.apache.lucene.search.MatchNoDocsQuery;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.util.BytesRef;
+import org.apache.lucene.util.automaton.CompiledAutomaton;
 import org.elasticsearch.common.ParsingException;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.compress.CompressedXContent;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.unit.Fuzziness;
 import org.elasticsearch.common.util.BigArrays;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.index.mapper.MapperService;
@@ -529,4 +534,57 @@ public void testWildcard() throws IOException {
         assertEquals(expected, builder.toQuery(createShardContext()));
     }
 
+    private static IntervalsSource buildFuzzySource(String term, String label, int prefixLength, boolean transpositions, int editDistance) {
+        FuzzyQuery fq = new FuzzyQuery(new Term("field", term), editDistance, prefixLength, 128, transpositions);
+        return XIntervals.multiterm(new CompiledAutomaton(fq.toAutomaton()), label);
+    }
+
+    public void testFuzzy() throws IOException {
+
+        String json = "{ \"intervals\" : { \"" + STRING_FIELD_NAME + "\": { " +
+            "\"fuzzy\" : { \"term\" : \"Term\" } } } }";
+        IntervalQueryBuilder builder = (IntervalQueryBuilder) parseQuery(json);
+
+        Query expected = new IntervalQuery(STRING_FIELD_NAME,
+            buildFuzzySource("term", "Term", FuzzyQueryBuilder.DEFAULT_PREFIX_LENGTH, true, Fuzziness.AUTO.asDistance("term")));
+        assertEquals(expected, builder.toQuery(createShardContext()));
+
+        String json_with_prefix = "{ \"intervals\" : { \"" + STRING_FIELD_NAME + "\": { " +
+            "\"fuzzy\" : { \"term\" : \"Term\", \"prefix_length\" : 2 } } } }";
+        builder = (IntervalQueryBuilder) parseQuery(json_with_prefix);
+        expected = new IntervalQuery(STRING_FIELD_NAME,
+            buildFuzzySource("term", "Term", 2, true, Fuzziness.AUTO.asDistance("term")));
+        assertEquals(expected, builder.toQuery(createShardContext()));
+
+        String json_with_fuzziness = "{ \"intervals\" : { \"" + STRING_FIELD_NAME + "\": { " +
+            "\"fuzzy\" : { \"term\" : \"Term\", \"prefix_length\" : 2, \"fuzziness\" : \"1\" } } } }";
+        builder = (IntervalQueryBuilder) parseQuery(json_with_fuzziness);
+        expected = new IntervalQuery(STRING_FIELD_NAME,
+            buildFuzzySource("term", "Term", 2, true, Fuzziness.ONE.asDistance("term")));
+        assertEquals(expected, builder.toQuery(createShardContext()));
+
+        String json_no_transpositions = "{ \"intervals\" : { \"" + STRING_FIELD_NAME + "\": { " +
+            "\"fuzzy\" : { \"term\" : \"Term\", \"prefix_length\" : 2, \"transpositions\" : false } } } }";
+        builder = (IntervalQueryBuilder) parseQuery(json_no_transpositions);
+        expected = new IntervalQuery(STRING_FIELD_NAME,
+            buildFuzzySource("term", "Term", 2, false, Fuzziness.AUTO.asDistance("term")));
+        assertEquals(expected, builder.toQuery(createShardContext()));
+
+        String json_with_analyzer = "{ \"intervals\" : { \"" + STRING_FIELD_NAME + "\": { " +
+            "\"fuzzy\" : { \"term\" : \"Term\", \"prefix_length\" : 2, \"analyzer\" : \"keyword\" } } } }";
+        builder = (IntervalQueryBuilder) parseQuery(json_with_analyzer);
+        expected = new IntervalQuery(STRING_FIELD_NAME,
+            buildFuzzySource("Term", "Term", 2, true, Fuzziness.AUTO.asDistance("term")));
+        assertEquals(expected, builder.toQuery(createShardContext()));
+
+        String json_with_fixfield = "{ \"intervals\" : { \"" + STRING_FIELD_NAME + "\": { " +
+            "\"fuzzy\" : { \"term\" : \"Term\", \"prefix_length\" : 2, \"fuzziness\" : \"1\", " +
+            "\"use_field\" : \"" + MASKED_FIELD + "\" } } } }";
+        builder = (IntervalQueryBuilder) parseQuery(json_with_fixfield);
+        expected = new IntervalQuery(STRING_FIELD_NAME, Intervals.fixField(MASKED_FIELD,
+            buildFuzzySource("term", "Term", 2, true, Fuzziness.ONE.asDistance("term"))));
+        assertEquals(expected, builder.toQuery(createShardContext()));
+
+    }
+
 }