Support highlighter

sdk-core/src/main/java/io/milvus/response/SearchResultsWrapper.java

@@ -253,7 +253,7 @@ public long getNumQueries() {
         return results.getNumQueries();
     }
 
-    private static final class Position {
+    public static final class Position {
         private final long offset;
         private final long k;
 
@@ -271,7 +271,7 @@ public long getK() {
         }
     }
 
-    private Position getOffsetByIndex(int indexOfTarget) {
+    public Position getOffsetByIndex(int indexOfTarget) {
         List<Long> kList = results.getTopksList();
 
         // if the server didn't return separate topK, use same topK value "0"

sdk-core/src/main/java/io/milvus/v2/service/vector/request/SearchReq.java

@@ -23,6 +23,7 @@
 import io.milvus.v2.common.IndexParam;
 import io.milvus.v2.service.collection.request.CreateCollectionReq;
 import io.milvus.v2.service.vector.request.data.BaseVector;
+import io.milvus.v2.service.vector.request.highlighter.Highlighter;
 
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -69,6 +70,9 @@ public class SearchReq {
     //     Boolean, Long, Double, String, List<Boolean>, List<Long>, List<Double>, List<String>
     private Map<String, Object> filterTemplateValues;
 
+    // milvus v2.6.9 supports highlighter for search results
+    private Highlighter highlighter;
+
     private SearchReq(SearchReqBuilder builder) {
         this.databaseName = builder.databaseName;
         this.collectionName = builder.collectionName;
@@ -95,6 +99,7 @@ private SearchReq(SearchReqBuilder builder) {
         this.functionScore = builder.functionScore;
         this.filterTemplateValues = builder.filterTemplateValues;
         this.timezone = builder.timezone;
+        this.highlighter = builder.highlighter;
     }
 
     // Getters and Setters
@@ -294,6 +299,10 @@ public void setFilterTemplateValues(Map<String, Object> filterTemplateValues) {
         this.filterTemplateValues = filterTemplateValues;
     }
 
+    public Highlighter getHighlighter() {
+        return highlighter;
+    }
+
     @Override
     public String toString() {
         return "SearchReq{" +
@@ -319,6 +328,7 @@ public String toString() {
                 ", groupSize=" + groupSize +
                 ", strictGroupSize=" + strictGroupSize +
                 ", ranker=" + ranker +
+                ", highlighter=" + (highlighter == null ? "null" : (highlighter.highlightType() + ":" + highlighter.getParams())) +
                 ", functionScore=" + functionScore +
 //                ", filterTemplateValues=" + filterTemplateValues +
                 '}';
@@ -354,6 +364,7 @@ public static class SearchReqBuilder {
         private CreateCollectionReq.Function ranker;
         private FunctionScore functionScore;
         private Map<String, Object> filterTemplateValues = new HashMap<>(); // default value
+        private Highlighter highlighter;
 
         private SearchReqBuilder() {
         }
@@ -487,6 +498,11 @@ public SearchReqBuilder filterTemplateValues(Map<String, Object> filterTemplateV
             return this;
         }
 
+        public SearchReqBuilder highlighter(Highlighter highlighter) {
+            this.highlighter = highlighter;
+            return this;
+        }
+
         public SearchReq build() {
             return new SearchReq(this);
         }

sdk-core/src/main/java/io/milvus/v2/service/vector/request/highlighter/Highlighter.java

@@ -0,0 +1,28 @@
+/*
+ * 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.
+ */
+
+package io.milvus.v2.service.vector.request.highlighter;
+
+import java.util.Map;
+
+public interface Highlighter {
+    String highlightType();
+
+    Map<String, String> getParams();
+}

sdk-core/src/main/java/io/milvus/v2/service/vector/request/highlighter/LexicalHighlighter.java

@@ -0,0 +1,170 @@
+/*
+ * 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.
+ */
+
+package io.milvus.v2.service.vector.request.highlighter;
+
+import io.milvus.common.utils.JsonUtils;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+public class LexicalHighlighter implements Highlighter {
+    private final List<HighlightQuery> highlightQueries;
+    private final Boolean highlightSearchText;
+    private final List<String> preTags;
+    private final List<String> postTags;
+    private final Integer fragmentOffset;
+    private final Integer fragmentSize;
+    private final Integer numOfFragments;
+
+    public LexicalHighlighter(LexicalHighlighterBuilder builder) {
+        this.highlightQueries = builder.highlightQueries;
+        this.highlightSearchText = builder.highlightSearchText;
+        this.preTags = builder.preTags;
+        this.postTags = builder.postTags;
+        this.fragmentOffset = builder.fragmentOffset;
+        this.fragmentSize = builder.fragmentSize;
+        this.numOfFragments = builder.numOfFragments;
+    }
+
+    @Override
+    public String highlightType() {
+        return "Lexical";
+    }
+
+    @Override
+    public Map<String, String> getParams() {
+        Map<String, String> params = new java.util.HashMap<>();
+        if (this.highlightQueries != null) {
+            // serialize the list of HighlightQuery to a JSON array string using Gson
+            params.put("highlight_queries", JsonUtils.toJson(this.highlightQueries));
+        }
+        if (this.highlightSearchText != null) {
+            params.put("highlight_search_text", this.highlightSearchText.toString());
+        }
+        if (this.preTags != null) {
+            params.put("pre_tags", JsonUtils.toJson(this.preTags));
+        }
+        if (this.postTags != null) {
+            params.put("post_tags", JsonUtils.toJson(this.postTags));
+        }
+        if (this.fragmentOffset != null) {
+            params.put("fragment_offset", this.fragmentOffset.toString());
+        }
+        if (this.fragmentSize != null) {
+            params.put("fragment_size", this.fragmentSize.toString());
+        }
+        if (this.numOfFragments != null) {
+            params.put("num_of_fragments", this.numOfFragments.toString());
+        }
+        return params;
+    }
+
+    public static class HighlightQuery {
+        public String type;
+        public String field;
+        public String text;
+
+        public HighlightQuery(String type, String field, String query) {
+            this.type = type;
+            this.field = field;
+            this.text = query;
+        }
+
+        @Override
+        public String toString() {
+            return JsonUtils.toJson(this);
+        }
+    }
+
+    public static class LexicalHighlighterBuilder {
+        private List<HighlightQuery> highlightQueries;
+        private Boolean highlightSearchText;
+        private List<String> preTags;
+        private List<String> postTags;
+        private Integer fragmentOffset;
+        private Integer fragmentSize;
+        private Integer numOfFragments;
+
+        public LexicalHighlighterBuilder() {
+        }
+
+        public LexicalHighlighterBuilder highlightQueries(List<HighlightQuery> queries) {
+            this.highlightQueries = queries;
+            return this;
+        }
+
+        public LexicalHighlighterBuilder addHighlightQuery(HighlightQuery q) {
+            if (this.highlightQueries == null) this.highlightQueries = new ArrayList<>();
+            this.highlightQueries.add(q);
+            return this;
+        }
+
+        public LexicalHighlighterBuilder highlightSearchText(Boolean highlightSearchText) {
+            this.highlightSearchText = highlightSearchText;
+            return this;
+        }
+
+        public LexicalHighlighterBuilder preTags(List<String> preTags) {
+            this.preTags = preTags;
+            return this;
+        }
+
+        public LexicalHighlighterBuilder addPreTag(String tag) {
+            if (this.preTags == null) this.preTags = new ArrayList<>();
+            this.preTags.add(tag);
+            return this;
+        }
+
+        public LexicalHighlighterBuilder postTags(List<String> postTags) {
+            this.postTags = postTags;
+            return this;
+        }
+
+        public LexicalHighlighterBuilder addPostTag(String tag) {
+            if (this.postTags == null) this.postTags = new ArrayList<>();
+            this.postTags.add(tag);
+            return this;
+        }
+
+        public LexicalHighlighterBuilder fragmentOffset(Integer offset) {
+            this.fragmentOffset = offset;
+            return this;
+        }
+
+        public LexicalHighlighterBuilder fragmentSize(Integer size) {
+            this.fragmentSize = size;
+            return this;
+        }
+
+        public LexicalHighlighterBuilder numOfFragments(Integer num) {
+            this.numOfFragments = num;
+            return this;
+        }
+
+        public LexicalHighlighter build() {
+            return new LexicalHighlighter(this);
+        }
+    }
+
+    public static LexicalHighlighterBuilder builder() {
+        return new LexicalHighlighterBuilder();
+    }
+}