SOLR-11736: Rename knn Streaming Expression to knnSearch and add new knn Stream Evaluator

solr/core/src/java/org/apache/solr/handler/StreamHandler.java

@@ -127,7 +127,7 @@ public class StreamHandler extends RequestHandlerBase implements SolrCoreAware,
         .withFunctionName("topic", TopicStream.class)
         .withFunctionName("commit", CommitStream.class)
         .withFunctionName("random", RandomStream.class)
-        .withFunctionName("knn", KnnStream.class)
+        .withFunctionName("knnSearch", KnnStream.class)
 
         // decorator streams
         .withFunctionName("merge", MergeStream.class)
@@ -305,6 +305,8 @@ public class StreamHandler extends RequestHandlerBase implements SolrCoreAware,
         .withFunctionName("colAt", ColumnAtEvaluator.class)
         .withFunctionName("setColumnLabels", SetColumnLabelsEvaluator.class)
         .withFunctionName("setRowLabels", SetRowLabelsEvaluator.class)
+        .withFunctionName("knn", KnnEvaluator.class)
+        .withFunctionName("getAttributes", GetAttributesEvaluator.class)
 
         // Boolean Stream Evaluators
 

solr/solrj/src/java/org/apache/solr/client/solrj/io/eval/GetAttributesEvaluator.java

@@ -0,0 +1,42 @@
+/*
+ * 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 org.apache.solr.client.solrj.io.eval;
+
+import java.io.IOException;
+import java.util.Locale;
+
+import org.apache.solr.client.solrj.io.stream.expr.StreamExpression;
+import org.apache.solr.client.solrj.io.stream.expr.StreamFactory;
+
+public class GetAttributesEvaluator extends RecursiveObjectEvaluator implements OneValueWorker {
+  private static final long serialVersionUID = 1;
+
+  public GetAttributesEvaluator(StreamExpression expression, StreamFactory factory) throws IOException {
+    super(expression, factory);
+  }
+
+  @Override
+  public Object doWork(Object value) throws IOException {
+    if(!(value instanceof Attributes)){
+      throw new IOException(String.format(Locale.ROOT,"Invalid expression %s - found type %s for value, expecting an Attributes",toExpression(constructingFactory), value.getClass().getSimpleName()));
+    } else {
+      Attributes attributes = (Attributes)value;
+      return attributes.getAttributes();
+    }
+  }
+}

solr/solrj/src/java/org/apache/solr/client/solrj/io/eval/KnnEvaluator.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 org.apache.solr.client.solrj.io.eval;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.TreeSet;
+
+import org.apache.commons.math3.ml.distance.CanberraDistance;
+import org.apache.commons.math3.ml.distance.DistanceMeasure;
+import org.apache.commons.math3.ml.distance.EarthMoversDistance;
+import org.apache.commons.math3.ml.distance.EuclideanDistance;
+import org.apache.commons.math3.ml.distance.ManhattanDistance;
+import org.apache.solr.client.solrj.io.stream.expr.StreamExpression;
+import org.apache.solr.client.solrj.io.stream.expr.StreamExpressionNamedParameter;
+import org.apache.solr.client.solrj.io.stream.expr.StreamFactory;
+
+public class KnnEvaluator extends RecursiveObjectEvaluator implements ManyValueWorker {
+  protected static final long serialVersionUID = 1L;
+
+  private DistanceMeasure distanceMeasure;
+
+  public KnnEvaluator(StreamExpression expression, StreamFactory factory) throws IOException{
+    super(expression, factory);
+
+    DistanceEvaluator.DistanceType type = null;
+    List<StreamExpressionNamedParameter> namedParams = factory.getNamedOperands(expression);
+    if(namedParams.size() > 0) {
+      if (namedParams.size() > 1) {
+        throw new IOException("distance function expects only one named parameter 'distance'.");
+      }
+
+      StreamExpressionNamedParameter namedParameter = namedParams.get(0);
+      String name = namedParameter.getName();
+      if (!name.equalsIgnoreCase("distance")) {
+        throw new IOException("distance function expects only one named parameter 'distance'.");
+      }
+
+      String typeParam = namedParameter.getParameter().toString().trim();
+      type= DistanceEvaluator.DistanceType.valueOf(typeParam);
+    } else {
+      type = DistanceEvaluator.DistanceType.euclidean;
+    }
+
+    if (type.equals(DistanceEvaluator.DistanceType.euclidean)) {
+      distanceMeasure = new EuclideanDistance();
+    } else if (type.equals(DistanceEvaluator.DistanceType.manhattan)) {
+      distanceMeasure = new ManhattanDistance();
+    } else if (type.equals(DistanceEvaluator.DistanceType.canberra)) {
+      distanceMeasure = new CanberraDistance();
+    } else if (type.equals(DistanceEvaluator.DistanceType.earthMovers)) {
+      distanceMeasure = new EarthMoversDistance();
+    }
+
+  }
+
+  @Override
+  public Object doWork(Object... values) throws IOException {
+
+    if(values.length < 3) {
+      throw new IOException("knn expects three parameters a Matrix, numeric array and k");
+    }
+
+    Matrix matrix = null;
+    double[] vec = null;
+    int k = 0;
+
+    if(values[0] instanceof Matrix) {
+      matrix = (Matrix)values[0];
+    } else {
+      throw new IOException("The first parameter for knn should be a matrix.");
+    }
+
+    if(values[1] instanceof List) {
+      List<Number> nums = (List<Number>)values[1];
+      vec = new double[nums.size()];
+      for(int i=0; i<nums.size(); i++) {
+        vec[i] = nums.get(i).doubleValue();
+      }
+    } else {
+      throw new IOException("The second parameter for knn should be a numeric array.");
+    }
+
+    if(values[2] instanceof Number) {
+      k = ((Number)values[2]).intValue();
+    } else {
+      throw new IOException("The third parameter for knn should be k.");
+    }
+
+    double[][] data = matrix.getData();
+
+    TreeSet<Neighbor> neighbors = new TreeSet();
+    for(int i=0; i<data.length; i++) {
+      double distance = distanceMeasure.compute(vec, data[i]);
+      neighbors.add(new Neighbor(i, distance));
+      if(neighbors.size() > k) {
+        neighbors.pollLast();
+      }
+    }
+
+    double[][] out = new double[neighbors.size()][];
+    List<String> rowLabels = matrix.getRowLabels();
+    List<String> newRowLabels = new ArrayList();
+    List<Number> distances = new ArrayList();
+    int i=-1;
+
+    while(neighbors.size() > 0) {
+      Neighbor neighbor = neighbors.pollFirst();
+      int rowIndex = neighbor.getRow();
+
+      if(rowLabels != null) {
+        newRowLabels.add(rowLabels.get(rowIndex));
+      }
+
+      out[++i] = data[rowIndex];
+      distances.add(neighbor.getDistance());
+    }
+
+    Matrix knn = new Matrix(out);
+
+    if(rowLabels != null) {
+      knn.setRowLabels(newRowLabels);
+    }
+
+    knn.setColumnLabels(matrix.getColumnLabels());
+    knn.setAttribute("distances", distances);
+    return knn;
+  }
+
+  public static class Neighbor implements Comparable<Neighbor> {
+
+    private Double distance;
+    private int row;
+
+    public Neighbor(int row, double distance) {
+      this.distance = distance;
+      this.row = row;
+    }
+
+    public int getRow() {
+      return this.row;
+    }
+
+    public Double getDistance() {
+      return distance;
+    }
+
+    public int compareTo(Neighbor neighbor) {
+      return this.distance.compareTo(neighbor.getDistance());
+    }
+  }
+
+}
+

solr/solrj/src/test/org/apache/solr/client/solrj/io/stream/StreamExpressionTest.java

@@ -933,7 +933,7 @@ public class StreamExpressionTest extends SolrCloudTestCase {
   }
 
   @Test
-  public void testKnnStream() throws Exception {
+  public void testKnnSearchStream() throws Exception {
 
     UpdateRequest update = new UpdateRequest();
     update.add(id, "1", "a_t", "hello world have a very nice day blah");
@@ -947,7 +947,7 @@ public class StreamExpressionTest extends SolrCloudTestCase {
     try {
       context.setSolrClientCache(cache);
       ModifiableSolrParams sParams = new ModifiableSolrParams(StreamingTest.mapParams(CommonParams.QT, "/stream"));
-      sParams.add("expr", "knn(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", rows=\"4\", fl=\"id, score\", mintf=\"1\")");
+      sParams.add("expr", "knnSearch(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", rows=\"4\", fl=\"id, score\", mintf=\"1\")");
       JettySolrRunner jetty = cluster.getJettySolrRunner(0);
       SolrStream solrStream = new SolrStream(jetty.getBaseUrl().toString() + "/collection1", sParams);
       List<Tuple> tuples = getTuples(solrStream);
@@ -955,26 +955,26 @@ public class StreamExpressionTest extends SolrCloudTestCase {
       assertOrder(tuples, 2, 3, 4);
 
       sParams = new ModifiableSolrParams(StreamingTest.mapParams(CommonParams.QT, "/stream"));
-      sParams.add("expr", "knn(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", k=\"2\", fl=\"id, score\", mintf=\"1\")");
+      sParams.add("expr", "knnSearch(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", k=\"2\", fl=\"id, score\", mintf=\"1\")");
       solrStream = new SolrStream(jetty.getBaseUrl().toString() + "/collection1", sParams);
       tuples = getTuples(solrStream);
       assertTrue(tuples.size() == 2);
       assertOrder(tuples, 2, 3);
 
       sParams = new ModifiableSolrParams(StreamingTest.mapParams(CommonParams.QT, "/stream"));
-      sParams.add("expr", "knn(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", rows=\"4\", fl=\"id, score\", mintf=\"1\", maxdf=\"0\")");
+      sParams.add("expr", "knnSearch(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", rows=\"4\", fl=\"id, score\", mintf=\"1\", maxdf=\"0\")");
       solrStream = new SolrStream(jetty.getBaseUrl().toString() + "/collection1", sParams);
       tuples = getTuples(solrStream);
       assertTrue(tuples.size() == 0);
 
       sParams = new ModifiableSolrParams(StreamingTest.mapParams(CommonParams.QT, "/stream"));
-      sParams.add("expr", "knn(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", rows=\"4\", fl=\"id, score\", mintf=\"1\", maxwl=\"1\")");
+      sParams.add("expr", "knnSearch(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", rows=\"4\", fl=\"id, score\", mintf=\"1\", maxwl=\"1\")");
       solrStream = new SolrStream(jetty.getBaseUrl().toString() + "/collection1", sParams);
       tuples = getTuples(solrStream);
       assertTrue(tuples.size() == 0);
 
       sParams = new ModifiableSolrParams(StreamingTest.mapParams(CommonParams.QT, "/stream"));
-      sParams.add("expr", "knn(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", rows=\"2\", fl=\"id, score\", mintf=\"1\", minwl=\"20\")");
+      sParams.add("expr", "knnSearch(" + COLLECTIONORALIAS + ", id=\"1\", qf=\"a_t\", rows=\"2\", fl=\"id, score\", mintf=\"1\", minwl=\"20\")");
       solrStream = new SolrStream(jetty.getBaseUrl().toString() + "/collection1", sParams);
       tuples = getTuples(solrStream);
       assertTrue(tuples.size() == 0);
@@ -7734,6 +7734,67 @@ public class StreamExpressionTest extends SolrCloudTestCase {
     assertEquals(density.doubleValue(), 0.007852638121596995, .00001);
   }
 
+  @Test
+  public void testKnn() throws Exception {
+    String cexpr = "let(echo=true," +
+        "               a=setRowLabels(matrix(array(1,1,1,0,0,0),"+
+        "                                     array(1,0,0,0,1,1),"+
+        "                                     array(0,0,0,1,1,1)), array(row1,row2,row3)),"+
+        "               b=array(0,0,0,1,1,1),"+
+        "               c=knn(a, b, 2),"+
+        "               d=getRowLabels(c),"+
+        "               e=getAttributes(c)," +
+        "               f=knn(a, b, 2, distance=manhattan)," +
+        "               g=getAttributes(f))";
+    ModifiableSolrParams paramsLoc = new ModifiableSolrParams();
+    paramsLoc.set("expr", cexpr);
+    paramsLoc.set("qt", "/stream");
+    String url = cluster.getJettySolrRunners().get(0).getBaseUrl().toString()+"/"+COLLECTIONORALIAS;
+    TupleStream solrStream = new SolrStream(url, paramsLoc);
+    StreamContext context = new StreamContext();
+    solrStream.setStreamContext(context);
+    List<Tuple> tuples = getTuples(solrStream);
+    assertTrue(tuples.size() == 1);
+
+    List<List<Number>> knnMatrix = (List<List<Number>>)tuples.get(0).get("c");
+    assertEquals(knnMatrix.size(), 2);
+
+    List<Number> row1 = knnMatrix.get(0);
+    assertEquals(row1.size(), 6);
+    assertEquals(row1.get(0).doubleValue(), 0.0, 0.0);
+    assertEquals(row1.get(1).doubleValue(), 0.0, 0.0);
+    assertEquals(row1.get(2).doubleValue(), 0.0, 0.0);
+    assertEquals(row1.get(3).doubleValue(), 1.0, 0.0);
+    assertEquals(row1.get(4).doubleValue(), 1.0, 0.0);
+    assertEquals(row1.get(5).doubleValue(), 1.0, 0.0);
+
+    List<Number> row2 = knnMatrix.get(1);
+    assertEquals(row2.size(), 6);
+
+    assertEquals(row2.get(0).doubleValue(), 1.0, 0.0);
+    assertEquals(row2.get(1).doubleValue(), 0.0, 0.0);
+    assertEquals(row2.get(2).doubleValue(), 0.0, 0.0);
+    assertEquals(row2.get(3).doubleValue(), 0.0, 0.0);
+    assertEquals(row2.get(4).doubleValue(), 1.0, 0.0);
+    assertEquals(row2.get(5).doubleValue(), 1.0, 0.0);
+
+    Map atts = (Map)tuples.get(0).get("e");
+    List<Number> dists = (List<Number>)atts.get("distances");
+    assertEquals(dists.size(), 2);
+    assertEquals(dists.get(0).doubleValue(), 0.0, 0.0);
+    assertEquals(dists.get(1).doubleValue(), 1.4142135623730951, 0.0);
+
+    List<String> rowLabels = (List<String>)tuples.get(0).get("d");
+    assertEquals(rowLabels.size(), 2);
+    assertEquals(rowLabels.get(0), "row3");
+    assertEquals(rowLabels.get(1), "row2");
+
+    atts = (Map)tuples.get(0).get("g");
+    dists = (List<Number>)atts.get("distances");
+    assertEquals(dists.size(), 2);
+    assertEquals(dists.get(0).doubleValue(), 0.0, 0.0);
+    assertEquals(dists.get(1).doubleValue(), 2.0, 0.0);
+  }
 
   @Test
   public void testIntegrate() throws Exception {