1 /***********************************************************************
2  * Copyright (c) 2013-2024 Commonwealth Computer Research, Inc.
3  * All rights reserved. This program and the accompanying materials
4  * are made available under the terms of the Apache License, Version 2.0
5  * which accompanies this distribution and is available at
6  * http://www.opensource.org/licenses/apache2.0.php.
7  ***********************************************************************/
8 
9 package org.locationtech.geomesa.lambda.stream.stats
10 
11 import org.geotools.api.feature.simple.SimpleFeatureType
12 import org.geotools.api.filter.Filter
13 import org.geotools.util.factory.Hints
14 import org.locationtech.geomesa.curve.TimePeriod.TimePeriod
15 import org.locationtech.geomesa.index.stats.GeoMesaStats.GeoMesaStatWriter
16 import org.locationtech.geomesa.index.stats.{GeoMesaStats, NoopStatWriter}
17 import org.locationtech.geomesa.lambda.stream.TransientStore
18 import org.locationtech.geomesa.utils.collection.SelfClosingIterator
19 import org.locationtech.geomesa.utils.stats._
20 
21 import scala.reflect.ClassTag
22 
23 class TransientStats(store: TransientStore) extends GeoMesaStats {
24 
25   override val writer: GeoMesaStatWriter = NoopStatWriter
26 
27   override def getCount(sft: SimpleFeatureType, filter: Filter, exact: Boolean, queryHints: Hints): Option[Long] =
28     Some(SelfClosingIterator(store.read(Option(filter).filter(_ != Filter.INCLUDE)).iterator()).length)
29 
30   override def getMinMax[T](
31       sft: SimpleFeatureType,
32       attribute: String,
33       filter: Filter,
34       exact: Boolean): Option[MinMax[T]] = getStat[MinMax[T]](sft, Stat.MinMax(attribute), filter, exact = true)
35 
36   override def getEnumeration[T](
37       sft: SimpleFeatureType,
38       attribute: String,
39       filter: Filter,
40       exact: Boolean): Option[EnumerationStat[T]] = {
41     if (!exact) { None } else {
42       getStat[EnumerationStat[T]](sft, Stat.Enumeration(attribute), filter, exact)
43     }
44   }
45 
46   override def getFrequency[T](
47       sft: SimpleFeatureType,
48       attribute: String,
49       precision: Int,
50       filter: Filter,
51       exact: Boolean): Option[Frequency[T]] = {
52     if (!exact) { None } else {
53       getStat[Frequency[T]](sft, Stat.Frequency(attribute, precision), filter, exact)
54     }
55   }
56 
57   override def getTopK[T](
58       sft: SimpleFeatureType,
59       attribute: String,
60       filter: Filter,
61       exact: Boolean): Option[TopK[T]] = {
62     if (!exact) { None } else {
63       getStat[TopK[T]](sft, Stat.TopK(attribute), filter, exact)
64     }
65   }
66 
67   override def getHistogram[T](
68       sft: SimpleFeatureType,
69       attribute: String,
70       bins: Int,
71       min: T,
72       max: T,
73       filter: Filter,
74       exact: Boolean): Option[Histogram[T]] = {
75     if (!exact) { None } else {
76       getStat[Histogram[T]](sft, Stat.Histogram(attribute, bins, min, max)(ClassTag(min.getClass)), filter, exact)
77     }
78   }
79 
80   override def getZ3Histogram(
81       sft: SimpleFeatureType,
82       geom: String,
83       dtg: String,
84       period: TimePeriod,
85       bins: Int,
86       filter: Filter,
87       exact: Boolean): Option[Z3Histogram] = {
88     if (!exact) { None } else {
89       getStat[Z3Histogram](sft, Stat.Z3Histogram(geom, dtg, period, bins), filter, exact)
90     }
91   }
92 
93   override def getStat[T <: Stat](
94       sft: SimpleFeatureType,
95       query: String,
96       filter: Filter,
97       exact: Boolean): Option[T] = {
98     if (!exact) { None } else {
99       val stat = Stat(sft, query).asInstanceOf[T]
100       SelfClosingIterator(store.read(Option(filter).filter(_ != Filter.INCLUDE)).iterator()).foreach(stat.observe)
101       Some(stat)
102     }
103   }
104 
105   override def close(): Unit = {}
106 }