opensearch-project · reta · Jul 5, 2023 · Jul 5, 2023 · Jul 5, 2023
@@ -3,9 +3,10 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ## [Unreleased]
 ### Added
-- Add support for knn_vector field type ([#529](https://github.com/opensearch-project/opensearch-java/pull/524))
+- Add support for knn_vector field type ([#524](https://github.com/opensearch-project/opensearch-java/pull/524))
 - Add translog option object and missing translog sync interval option in index settings ([#518](https://github.com/opensearch-project/opensearch-java/pull/518))
 - Adds the option to set slices=auto for UpdateByQueryRequest, DeleteByQueryRequest and ReindexRequest ([#538](https://github.com/opensearch-project/opensearch-java/pull/538))
+- Add support for approximate k-NN queries ([#548](https://github.com/opensearch-project/opensearch-java/pull/548))
 
 ### Dependencies
 - Bumps `com.github.jk1.dependency-license-report` from 2.2 to 2.4

@@ -78,6 +78,14 @@ public final Builder parameters(@Nullable Map<String, JsonData> map) {
             return this;
         }
 
+        /**
+         * API name: {@code parameters}
+         */
+        public final Builder parameters(String key, JsonData value) {
+            this.parameters = _mapPut(this.parameters, key, value);
+            return this;
+        }
+
         /**
          * Builds a {@link KnnVectorMethod}.
          *
@@ -194,10 +202,12 @@ protected void serializeInternal(JsonGenerator generator, JsonpMapper mapper) {
 
         if (this.parameters != null) {
             generator.writeKey("parameters");
+            generator.writeStartObject();
             for (Map.Entry<String, JsonData> item0 : this.parameters.entrySet()) {
                 generator.writeKey(item0.getKey());
                 item0.getValue().serialize(generator, mapper);
             }
+            generator.writeEnd();
         }
 
     }

@@ -65,6 +65,13 @@ public final Builder method(@Nullable KnnVectorMethod value) {
 			return this;
 		}
 
+		/**
+		 * API name: {@code method}
+		 */
+		public final Builder method(Function<KnnVectorMethod.Builder, ObjectBuilder<KnnVectorMethod>> fn) {
+			return this.method(fn.apply(new KnnVectorMethod.Builder()).build());
+		}
+
 		/**
 		 * Builds a {@link KnnVectorProperty}.
 		 *

@@ -0,0 +1,202 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.client.opensearch._types.query_dsl;
+
+import jakarta.json.stream.JsonGenerator;
+import java.util.function.Function;
+import javax.annotation.Nullable;
+import org.opensearch.client.json.JsonpDeserializable;
+import org.opensearch.client.json.JsonpDeserializer;
+import org.opensearch.client.json.JsonpMapper;
+import org.opensearch.client.json.ObjectBuilderDeserializer;
+import org.opensearch.client.json.ObjectDeserializer;
+import org.opensearch.client.util.ApiTypeHelper;
+import org.opensearch.client.util.ObjectBuilder;
+
+@JsonpDeserializable
+public class KnnQuery extends QueryBase implements QueryVariant {
+    private final String field;
+    private final float[] vector;
+    private final int k;
+    @Nullable
+    private final Query filter;
+
+    private KnnQuery(Builder builder) {
+        super(builder);
+
+        this.field = ApiTypeHelper.requireNonNull(builder.field, this, "field");
+        this.vector = ApiTypeHelper.requireNonNull(builder.vector, this, "vector");
+        this.k = ApiTypeHelper.requireNonNull(builder.k, this, "k");
+        this.filter = builder.filter;
+    }
+
+    public static KnnQuery of(Function<Builder, ObjectBuilder<KnnQuery>> fn) {
+        return fn.apply(new Builder()).build();
+    }
+
+    /**
+     * Query variant kind.
+     * @return The query variant kind.
+     */
+    @Override
+    public Query.Kind _queryKind() {
+        return Query.Kind.Knn;
+    }
+
+    /**
+     * Required - The target field.
+     * @return The target field.
+     */
+    public final String field() {
+        return this.field;
+    }
+
+    /**
+     * Required - The vector to search for.
+     * @return The vector to search for.
+     */
+    public final float[] vector() {
+        return this.vector;
+    }
+
+    /**
+     * Required - The number of neighbors the search of each graph will return.
+     * @return The number of neighbors to return.
+     */
+    public final int k() {
+        return this.k;
+    }
+
+    /**
+     * Optional - A query to filter the results of the query.
+     * @return The filter query.
+     */
+    @Nullable
+    public final Query filter() {
+        return this.filter;
+    }
+
+    @Override
+    protected void serializeInternal(JsonGenerator generator, JsonpMapper mapper) {
+        generator.writeStartObject(this.field);
+
+        super.serializeInternal(generator, mapper);
+
+        // TODO: Implement the rest of the serialization.
+
+        generator.writeKey("vector");
+        generator.writeStartArray();
+        for (float value : this.vector) {
+            generator.write(value);
+        }
+        generator.writeEnd();
+
+        generator.write("k", this.k);
+
+        if (this.filter != null) {
+            generator.writeKey("filter");
+            this.filter.serialize(generator, mapper);
+        }
+
+        generator.writeEnd();
+    }
+
+    /**
+     * Builder for {@link KnnQuery}.
+     */
+    public static class Builder extends QueryBase.AbstractBuilder<Builder> implements ObjectBuilder<KnnQuery> {
+        @Nullable
+        private String field;
+        @Nullable
+        private float[] vector;
+        @Nullable
+        private Integer k;
+        @Nullable
+        private Query filter;
+
+        /**
+         * Required - The target field.
+         * @param field The target field.
+         * @return This builder.
+         */
+        public Builder field(@Nullable String field) {
+            this.field = field;
+            return this;
+        }
+
+        /**
+         * Required - The vector to search for.
+         *
+         * @param vector The vector to search for.
+         * @return This builder.
+         */
+        public Builder vector(@Nullable float[] vector) {
+            this.vector = vector;
+            return this;
+        }
+
+        /**
+         * Required - The number of neighbors the search of each graph will return.
+         *
+         * @param k The number of neighbors to return.
+         * @return This builder.
+         */
+        public Builder k(@Nullable Integer k) {
+            this.k = k;
+            return this;
+        }
+
+        /**
+         * Optional - A query to filter the results of the knn query.
+         *
+         * @param filter The filter query.
+         * @return This builder.
+         */
+        public Builder filter(@Nullable Query filter) {
+            this.filter = filter;
+            return this;
+        }
+
+        @Override
+        protected Builder self() {
+            return this;
+        }
+
+        /**
+         * Builds a {@link KnnQuery}.
+         *
+         * @return The built {@link KnnQuery}.
+         */
+        @Override
+        public KnnQuery build() {
+            _checkSingleUse();
+
+            return new KnnQuery(this);
+        }
+    }
+
+    public static final JsonpDeserializer<KnnQuery> _DESERIALIZER = ObjectBuilderDeserializer
+            .lazy(Builder::new, KnnQuery::setupKnnQueryDeserializer);
+
+    protected static void setupKnnQueryDeserializer(ObjectDeserializer<Builder> op) {
+        setupQueryBaseDeserializer(op);
+        op.add((b, v) -> {
+            float[] vector = new float[v.size()];
+            int i = 0;
+            for (Float value : v) {
+                vector[i++] = value;
+            }
+            b.vector(vector);
+        }, JsonpDeserializer.arrayDeserializer(JsonpDeserializer.floatDeserializer()), "vector");
+        op.add(Builder::k, JsonpDeserializer.integerDeserializer(), "k");
+        op.add(Builder::filter, Query._DESERIALIZER, "filter");
+
+        op.setKey(Builder::field, JsonpDeserializer.stringDeserializer());
+    }
+}
@@ -103,6 +103,8 @@ public enum Kind implements JsonEnum {
 
 		Intervals("intervals"),
 
+		Knn("knn"),
+
 		Match("match"),
 
 		MatchAll("match_all"),
@@ -535,6 +537,23 @@ public IntervalsQuery intervals() {
 		return TaggedUnionUtils.get(this, Kind.Intervals);
 	}
 
+	/**
+	 * Is this variant instance of kind {@code knn}?
+	 */
+	public boolean isKnn() {
+		return _kind == Kind.Knn;
+	}
+
+	/**
+	 * Get the {@code knn} variant value.
+	 *
+	 * @throws IllegalStateException
+	 *             if the current variant is not of the {@code knn} kind.
+	 */
+	public KnnQuery knn() {
+		return TaggedUnionUtils.get(this, Kind.Knn);
+	}
+
 	/**
 	 * Is this variant instance of kind {@code match}?
 	 */
@@ -1340,6 +1359,16 @@ public ObjectBuilder<Query> intervals(Function<IntervalsQuery.Builder, ObjectBui
 			return this.intervals(fn.apply(new IntervalsQuery.Builder()).build());
 		}
 
+		public ObjectBuilder<Query> knn(KnnQuery v) {
+			this._kind = Kind.Knn;
+			this._value = v;
+			return this;
+		}
+
+		public ObjectBuilder<Query> knn(Function<KnnQuery.Builder, ObjectBuilder<KnnQuery>> fn) {
+			return this.knn(fn.apply(new KnnQuery.Builder()).build());
+		}
+
 		public ObjectBuilder<Query> match(MatchQuery v) {
 			this._kind = Kind.Match;
 			this._value = v;
@@ -1728,6 +1757,7 @@ protected static void setupQueryDeserializer(ObjectDeserializer<Builder> op) {
 		op.add(Builder::hasParent, HasParentQuery._DESERIALIZER, "has_parent");
 		op.add(Builder::ids, IdsQuery._DESERIALIZER, "ids");
 		op.add(Builder::intervals, IntervalsQuery._DESERIALIZER, "intervals");
+		op.add(Builder::knn, KnnQuery._DESERIALIZER, "knn");
 		op.add(Builder::match, MatchQuery._DESERIALIZER, "match");
 		op.add(Builder::matchAll, MatchAllQuery._DESERIALIZER, "match_all");
 		op.add(Builder::matchBoolPrefix, MatchBoolPrefixQuery._DESERIALIZER, "match_bool_prefix");

@@ -182,6 +182,13 @@ public static IntervalsQuery.Builder intervals() {
 		return new IntervalsQuery.Builder();
 	}
 
+	/**
+	 * Creates a builder for the {@link KnnQuery knn} {@code Query} variant.
+	 */
+	public static KnnQuery.Builder knn() {
+		return new KnnQuery.Builder();
+	}
+
 	/**
 	 * Creates a builder for the {@link MatchQuery match} {@code Query} variant.
 	 */

@@ -1066,7 +1066,7 @@ protected void serializeInternal(JsonGenerator generator, JsonpMapper mapper) {
 
 		}
 		if (this.knnAlgoParamEfSearch != null) {
-			generator.writeKey("knn.algo_param_ef_search");
+			generator.writeKey("knn.algo_param.ef_search");
 			generator.write(this.knnAlgoParamEfSearch);
 
 		}