Enabled the IVF algorithm to work with Filters of K-NN Query.

CHANGELOG.md

@@ -15,6 +15,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 ## [Unreleased 2.x](https://github.com/opensearch-project/k-NN/compare/2.9...2.x)
 ### Features
 ### Enhancements
+* Enabled the IVF algorithm to work with Filters of K-NN Query. [#1013](https://github.com/opensearch-project/k-NN/pull/1013)
 ### Bug Fixes
 ### Infrastructure
 ### Documentation

src/main/java/org/opensearch/knn/index/query/KNNWeight.java

@@ -6,6 +6,7 @@
 package org.opensearch.knn.index.query;
 
 import lombok.extern.log4j.Log4j2;
+import org.apache.commons.lang.StringUtils;
 import org.apache.lucene.index.BinaryDocValues;
 import org.apache.lucene.index.DocValues;
 import org.apache.lucene.search.FilteredDocIdSetIterator;
@@ -49,6 +50,7 @@
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.concurrent.ExecutionException;
 import java.util.stream.Collectors;
@@ -290,7 +292,7 @@ private Map<Integer, Float> doExactSearch(final LeafReaderContext leafReaderCont
         float[] queryVector = this.knnQuery.getQueryVector();
         try {
             final BinaryDocValues values = DocValues.getBinary(leafReaderContext.reader(), fieldInfo.getName());
-            final SpaceType spaceType = SpaceType.getSpace(fieldInfo.getAttribute(SPACE_TYPE));
+            final SpaceType spaceType = getSpaceType(fieldInfo);
             // Creating min heap and init with MAX DocID and Score as -INF.
             final HitQueue queue = new HitQueue(this.knnQuery.getK(), true);
             ScoreDoc topDoc = queue.top();
@@ -351,4 +353,20 @@ public static float normalizeScore(float score) {
         if (score >= 0) return 1 / (1 + score);
         return -score + 1;
     }
+
+    private SpaceType getSpaceType(final FieldInfo fieldInfo) {
+        final String spaceTypeString = fieldInfo.getAttribute(SPACE_TYPE);
+        if (StringUtils.isNotEmpty(spaceTypeString)) {
+            return SpaceType.getSpace(spaceTypeString);
+        }
+
+        final String modelId = fieldInfo.getAttribute(MODEL_ID);
+        if (StringUtils.isNotEmpty(modelId)) {
+            ModelMetadata modelMetadata = modelDao.getMetadata(modelId);
+            return modelMetadata.getSpaceType();
+        }
+        throw new IllegalArgumentException(
+            String.format(Locale.ROOT, "Unable to find the Space Type from Field Info attribute for field %s", fieldInfo.getName())
+        );
+    }
 }

src/test/java/org/opensearch/knn/index/FaissIT.java

@@ -221,7 +221,7 @@ public void testDocDeletion() throws IOException {
         deleteKnnDoc(INDEX_NAME, "1");
     }
 
-    public void testEndToEnd_fromModel() throws IOException, InterruptedException {
+    public void testKNNQuery_withModelDifferentCombination_thenSuccess() throws IOException, InterruptedException {
         String modelId = "test-model";
         int dimension = 128;
 
@@ -270,10 +270,9 @@ public void testEndToEnd_fromModel() throws IOException, InterruptedException {
         // Index some documents
         int numDocs = 100;
         for (int i = 0; i < numDocs; i++) {
-            Float[] indexVector = new Float[dimension];
+            float[] indexVector = new float[dimension];
             Arrays.fill(indexVector, (float) i);
-
-            addKnnDoc(indexName, Integer.toString(i), fieldName, indexVector);
+            addKnnDocWithAttributes(indexName, Integer.toString(i), fieldName, indexVector, ImmutableMap.of("rating", String.valueOf(i)));
         }
 
         // Run search and ensure that the values returned are expected
@@ -287,6 +286,34 @@ public void testEndToEnd_fromModel() throws IOException, InterruptedException {
         for (int i = 0; i < k; i++) {
             assertEquals(numDocs - i - 1, Integer.parseInt(results.get(i).getDocId()));
         }
+
+        // doing exact search with filters
+        Response exactSearchFilteredResponse = searchKNNIndex(
+            indexName,
+            new KNNQueryBuilder(fieldName, queryVector, k, QueryBuilders.rangeQuery("rating").gte("90").lte("99")),
+            k
+        );
+        List<KNNResult> exactSearchFilteredResults = parseSearchResponse(
+            EntityUtils.toString(exactSearchFilteredResponse.getEntity()),
+            fieldName
+        );
+        for (int i = 0; i < k; i++) {
+            assertEquals(numDocs - i - 1, Integer.parseInt(exactSearchFilteredResults.get(i).getDocId()));
+        }
+
+        // doing exact search with filters
+        Response aNNSearchFilteredResponse = searchKNNIndex(
+            indexName,
+            new KNNQueryBuilder(fieldName, queryVector, k, QueryBuilders.rangeQuery("rating").gte("80").lte("99")),
+            k
+        );
+        List<KNNResult> aNNSearchFilteredResults = parseSearchResponse(
+            EntityUtils.toString(aNNSearchFilteredResponse.getEntity()),
+            fieldName
+        );
+        for (int i = 0; i < k; i++) {
+            assertEquals(numDocs - i - 1, Integer.parseInt(aNNSearchFilteredResults.get(i).getDocId()));
+        }
     }
 
     @SneakyThrows

src/testFixtures/java/org/opensearch/knn/KNNRestTestCase.java

@@ -1322,4 +1322,26 @@ protected void addKnnDocWithAttributes(String docId, float[] vector, Map<String,
         Response response = client().performRequest(request);
         assertEquals(request.getEndpoint() + ": failed", RestStatus.OK, RestStatus.fromCode(response.getStatusLine().getStatusCode()));
     }
+
+    protected void addKnnDocWithAttributes(
+        String indexName,
+        String docId,
+        String vectorFieldName,
+        float[] vector,
+        Map<String, String> fieldValues
+    ) throws IOException {
+        Request request = new Request("POST", "/" + indexName + "/_doc/" + docId + "?refresh=true");
+
+        final XContentBuilder builder = XContentFactory.jsonBuilder().startObject().field(vectorFieldName, vector);
+        for (String fieldName : fieldValues.keySet()) {
+            builder.field(fieldName, fieldValues.get(fieldName));
+        }
+        builder.endObject();
+        request.setJsonEntity(Strings.toString(builder));
+        client().performRequest(request);
+
+        request = new Request("POST", "/" + indexName + "/_refresh");
+        Response response = client().performRequest(request);
+        assertEquals(request.getEndpoint() + ": failed", RestStatus.OK, RestStatus.fromCode(response.getStatusLine().getStatusCode()));
+    }
 }