Onheap impl startree minmax

server/src/main/java/org/opensearch/index/compositeindex/datacube/startree/aggregators/CountValueAggregator.java

@@ -18,7 +18,7 @@
 public class CountValueAggregator implements ValueAggregator<Long> {
     public static final StarTreeNumericType VALUE_AGGREGATOR_TYPE = StarTreeNumericType.LONG;
     public static final long DEFAULT_INITIAL_VALUE = 1L;
-    private StarTreeNumericType starTreeNumericType;
+    private final StarTreeNumericType starTreeNumericType;
 
     public CountValueAggregator(StarTreeNumericType starTreeNumericType) {
         this.starTreeNumericType = starTreeNumericType;
@@ -36,21 +36,38 @@ public StarTreeNumericType getAggregatedValueType() {
 
     @Override
     public Long getInitialAggregatedValueForSegmentDocValue(Long segmentDocValue) {
+
+        if (segmentDocValue == null) {
+            return getIdentityMetricValue();
+        }
+
         return DEFAULT_INITIAL_VALUE;
     }
 
     @Override
     public Long mergeAggregatedValueAndSegmentValue(Long value, Long segmentDocValue) {
+        if (value == null) {
+            return getIdentityMetricValue();
+        }
         return value + 1;
     }
 
     @Override
     public Long mergeAggregatedValues(Long value, Long aggregatedValue) {
+        if (value == null) {
+            value = getIdentityMetricValue();
+        }
+        if (aggregatedValue == null) {
+            aggregatedValue = getIdentityMetricValue();
+        }
         return value + aggregatedValue;
     }
 
     @Override
     public Long getInitialAggregatedValue(Long value) {
+        if (value == null) {
+            return getIdentityMetricValue();
+        }
         return value;
     }
 
@@ -68,4 +85,9 @@ public Long toLongValue(Long value) {
     public Long toStarTreeNumericTypeValue(Long value) {
         return value;
     }
+
+    @Override
+    public Long getIdentityMetricValue() {
+        return 0L;
+    }
 }

server/src/main/java/org/opensearch/index/compositeindex/datacube/startree/aggregators/MaxValueAggregator.java

@@ -0,0 +1,112 @@
+/*
+ * 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.index.compositeindex.datacube.startree.aggregators;
+
+import org.apache.lucene.util.NumericUtils;
+import org.opensearch.index.compositeindex.datacube.MetricStat;
+import org.opensearch.index.compositeindex.datacube.startree.aggregators.numerictype.StarTreeNumericType;
+
+/**
+ * Max value aggregator for star tree
+ *
+ * @opensearch.experimental
+ */
+public class MaxValueAggregator implements ValueAggregator<Double> {
+
+    public static final StarTreeNumericType VALUE_AGGREGATOR_TYPE = StarTreeNumericType.DOUBLE;
+    private final StarTreeNumericType starTreeNumericType;
+
+    public MaxValueAggregator(StarTreeNumericType starTreeNumericType) {
+        this.starTreeNumericType = starTreeNumericType;
+    }
+
+    @Override
+    public MetricStat getAggregationType() {
+        return MetricStat.MAX;
+    }
+
+    @Override
+    public StarTreeNumericType getAggregatedValueType() {
+        return VALUE_AGGREGATOR_TYPE;
+    }
+
+    @Override
+    public Double getInitialAggregatedValueForSegmentDocValue(Long segmentDocValue) {
+        if (segmentDocValue == null) {
+            return getIdentityMetricValue();
+        }
+        return starTreeNumericType.getDoubleValue(segmentDocValue);
+    }
+
+    @Override
+    public Double mergeAggregatedValueAndSegmentValue(Double value, Long segmentDocValue) {
+        if (segmentDocValue == null && value != null) {
+            return value;
+        } else if (segmentDocValue != null && value == null) {
+            return starTreeNumericType.getDoubleValue(segmentDocValue);
+        } else if (segmentDocValue == null) {
+            return getIdentityMetricValue();
+        }
+        return Math.max(value, starTreeNumericType.getDoubleValue(segmentDocValue));
+    }
+
+    @Override
+    public Double mergeAggregatedValues(Double value, Double aggregatedValue) {
+        if (value == null && aggregatedValue != null) {
+            return aggregatedValue;
+        } else if (value != null && aggregatedValue == null) {
+            return value;
+        } else if (value == null) {
+            return getIdentityMetricValue();
+        }
+        return Math.max(value, aggregatedValue);
+    }
+
+    @Override
+    public Double getInitialAggregatedValue(Double value) {
+        if (value == null) {
+            return getIdentityMetricValue();
+        }
+        return value;
+    }
+
+    @Override
+    public int getMaxAggregatedValueByteSize() {
+        return Double.BYTES;
+    }
+
+    @Override
+    public Long toLongValue(Double value) {
+        try {
+            if (value == null) {
+                return null;
+            }
+            return NumericUtils.doubleToSortableLong(value);
+        } catch (Exception e) {
+            throw new IllegalStateException("Cannot convert " + value + " to sortable long", e);
+        }
+    }
+
+    @Override
+    public Double toStarTreeNumericTypeValue(Long value) {
+        try {
+            if (value == null) {
+                return getIdentityMetricValue();
+            }
+            return starTreeNumericType.getDoubleValue(value);
+        } catch (Exception e) {
+            throw new IllegalStateException("Cannot convert " + value + " to sortable aggregation type", e);
+        }
+    }
+
+    @Override
+    public Double getIdentityMetricValue() {
+        // in present aggregations, if the metric behind max is missing, we treat it as null
+        return null;
+    }
+}

server/src/main/java/org/opensearch/index/compositeindex/datacube/startree/aggregators/MetricAggregatorInfo.java

@@ -16,6 +16,7 @@
 
 /**
  * Builds aggregation function and doc values field pair to support various aggregations
+ *
  * @opensearch.experimental
  */
 public class MetricAggregatorInfo implements Comparable<MetricAggregatorInfo> {
@@ -79,7 +80,15 @@ public StarTreeNumericType getAggregatedValueType() {
      * @return field name with metric type and field
      */
     public String toFieldName() {
-        return starFieldName + DELIMITER + field + DELIMITER + metricStat.getTypeName();
+        return toFieldName(starFieldName, field, metricStat.getTypeName());
+
+    }
+
+    /**
+     * @return field name with star-tree field name metric type and field
+     */
+    public static String toFieldName(String starFieldName, String field, String metricName) {
+        return starFieldName + DELIMITER + field + DELIMITER + metricName;
     }
 
     @Override
@@ -94,7 +103,7 @@ public boolean equals(Object obj) {
         }
         if (obj instanceof MetricAggregatorInfo) {
             MetricAggregatorInfo anotherPair = (MetricAggregatorInfo) obj;
-            return metricStat == anotherPair.metricStat && field.equals(anotherPair.field);
+            return metricStat.equals(anotherPair.metricStat) && field.equals(anotherPair.field);
         }
         return false;
     }

server/src/main/java/org/opensearch/index/compositeindex/datacube/startree/aggregators/MinValueAggregator.java

@@ -0,0 +1,112 @@
+/*
+ * 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.index.compositeindex.datacube.startree.aggregators;
+
+import org.apache.lucene.util.NumericUtils;
+import org.opensearch.index.compositeindex.datacube.MetricStat;
+import org.opensearch.index.compositeindex.datacube.startree.aggregators.numerictype.StarTreeNumericType;
+
+/**
+ * Min value aggregator for star tree
+ *
+ * @opensearch.experimental
+ */
+public class MinValueAggregator implements ValueAggregator<Double> {
+
+    public static final StarTreeNumericType VALUE_AGGREGATOR_TYPE = StarTreeNumericType.DOUBLE;
+    private final StarTreeNumericType starTreeNumericType;
+
+    public MinValueAggregator(StarTreeNumericType starTreeNumericType) {
+        this.starTreeNumericType = starTreeNumericType;
+    }
+
+    @Override
+    public MetricStat getAggregationType() {
+        return MetricStat.MIN;
+    }
+
+    @Override
+    public StarTreeNumericType getAggregatedValueType() {
+        return VALUE_AGGREGATOR_TYPE;
+    }
+
+    @Override
+    public Double getInitialAggregatedValueForSegmentDocValue(Long segmentDocValue) {
+        if (segmentDocValue == null) {
+            return getIdentityMetricValue();
+        }
+        return starTreeNumericType.getDoubleValue(segmentDocValue);
+    }
+
+    @Override
+    public Double mergeAggregatedValueAndSegmentValue(Double value, Long segmentDocValue) {
+        if (segmentDocValue == null && value != null) {
+            return value;
+        } else if (segmentDocValue != null && value == null) {
+            return starTreeNumericType.getDoubleValue(segmentDocValue);
+        } else if (segmentDocValue == null) {
+            return getIdentityMetricValue();
+        }
+        return Math.min(value, starTreeNumericType.getDoubleValue(segmentDocValue));
+    }
+
+    @Override
+    public Double mergeAggregatedValues(Double value, Double aggregatedValue) {
+        if (value == null && aggregatedValue != null) {
+            return aggregatedValue;
+        } else if (value != null && aggregatedValue == null) {
+            return value;
+        } else if (value == null) {
+            return getIdentityMetricValue();
+        }
+        return Math.min(value, aggregatedValue);
+    }
+
+    @Override
+    public Double getInitialAggregatedValue(Double value) {
+        if (value == null) {
+            return getIdentityMetricValue();
+        }
+        return value;
+    }
+
+    @Override
+    public int getMaxAggregatedValueByteSize() {
+        return Double.BYTES;
+    }
+
+    @Override
+    public Long toLongValue(Double value) {
+        try {
+            if (value == null) {
+                return null;
+            }
+            return NumericUtils.doubleToSortableLong(value);
+        } catch (Exception e) {
+            throw new IllegalStateException("Cannot convert " + value + " to sortable long", e);
+        }
+    }
+
+    @Override
+    public Double toStarTreeNumericTypeValue(Long value) {
+        try {
+            if (value == null) {
+                return getIdentityMetricValue();
+            }
+            return starTreeNumericType.getDoubleValue(value);
+        } catch (Exception e) {
+            throw new IllegalStateException("Cannot convert " + value + " to sortable aggregation type", e);
+        }
+    }
+
+    @Override
+    public Double getIdentityMetricValue() {
+        // in present aggregations, if the metric behind min is missing, we treat it as null
+        return null;
+    }
+}