bugfix(centroid): fix precision loss from long to double

.gitignore

@@ -99,3 +99,5 @@ gradle-app.setting
 ### VisualStudioCode template
 .vscode
 
+.settings/
+.project

README.md

@@ -16,7 +16,7 @@ Please note that [geo_shape data type](https://www.elastic.co/guide/en/elasticse
 ### Install
 
 Install plugin with:
-`./bin/elasticsearch-plugin install https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v8.19.6.0/geopoint-clustering-aggregation-8.19.6.0.zip`
+`./bin/elasticsearch-plugin install https://github.com/opendatasoft/elasticsearch-aggregation-geoclustering/releases/download/v8.19.6.1/geopoint-clustering-aggregation-8.19.6.1.zip`
 
 
 ### Quickstart

gradle.properties

@@ -1,2 +1,2 @@
 es_version = 8.19.6
-plugin_version = 8.19.6.0
+plugin_version = 8.19.6.1

src/main/java/com/opendatasoft/elasticsearch/search/aggregations/bucket/geopointclustering/InternalGeoPointClustering.java

@@ -1,6 +1,5 @@
 package com.opendatasoft.elasticsearch.search.aggregations.bucket.geopointclustering;
 
-import org.apache.lucene.geo.GeoEncodingUtils;
 import org.elasticsearch.common.geo.GeoPoint;
 import org.elasticsearch.common.geo.GeoUtils;
 import org.elasticsearch.common.io.stream.StreamInput;
@@ -35,7 +34,7 @@ static class Bucket extends InternalMultiBucketAggregation.InternalBucketWritabl
         protected long hashAsLong;
         protected GeoPoint centroid;
         protected long docCount;
-        protected InternalAggregations aggregations;  // sub-aggregations for this bucket
+        protected InternalAggregations aggregations; // sub-aggregations for this bucket
         protected boolean visited = false;
         protected Set<Long> geohashesList;
 
@@ -54,10 +53,13 @@ static class Bucket extends InternalMultiBucketAggregation.InternalBucketWritabl
         private Bucket(StreamInput in) throws IOException {
             hashAsLong = in.readLong();
             docCount = in.readVLong();
-            final long hash = in.readLong();
-            centroid = new GeoPoint(decodeLatitude(hash), decodeLongitude(hash));
+            double lat = in.readDouble();
+            double lon = in.readDouble();
+            centroid = new GeoPoint(lat, lon);
             visited = in.readBoolean();
             aggregations = InternalAggregations.readFrom(in);
+            geohashesList = new HashSet<>();
+            geohashesList.add(hashAsLong);
         }
 
         /**
@@ -67,7 +69,8 @@ private Bucket(StreamInput in) throws IOException {
         public void writeTo(StreamOutput out) throws IOException {
             out.writeLong(hashAsLong);
             out.writeVLong(docCount);
-            out.writeLong(encodeLatLon(centroid.lat(), centroid.lon()));
+            out.writeDouble(centroid.lat());
+            out.writeDouble(centroid.lon());
             out.writeBoolean(visited);
             aggregations.writeTo(out);
         }
@@ -118,14 +121,13 @@ public boolean equals(Object o) {
             if (this == o) return true;
             if (o == null || getClass() != o.getClass()) return false;
             Bucket bucket = (Bucket) o;
-            return hashAsLong == bucket.hashAsLong && docCount == bucket.docCount && Objects.equals(aggregations, bucket.aggregations);
+            return (hashAsLong == bucket.hashAsLong && docCount == bucket.docCount && Objects.equals(aggregations, bucket.aggregations));
         }
 
         @Override
         public int hashCode() {
             return Objects.hash(hashAsLong, docCount, aggregations);
         }
-
     }
 
     private final double radius;
@@ -170,20 +172,6 @@ protected void doWriteTo(StreamOutput out) throws IOException {
         out.writeCollection((Collection<? extends Writeable>) buckets);
     }
 
-    public static long encodeLatLon(double lat, double lon) {
-        return (Integer.toUnsignedLong(GeoEncodingUtils.encodeLatitude(lat)) << 32) | Integer.toUnsignedLong(
-            GeoEncodingUtils.encodeLongitude(lon)
-        );
-    }
-
-    public static double decodeLatitude(long encodedLatLon) {
-        return GeoEncodingUtils.decodeLatitude((int) (encodedLatLon >>> 32));
-    }
-
-    public static double decodeLongitude(long encodedLatLon) {
-        return GeoEncodingUtils.decodeLongitude((int) (encodedLatLon & 0xFFFFFFFFL));
-    }
-
     protected Reader<Bucket> getBucketReader() {
         return Bucket::new;
     }
@@ -254,7 +242,6 @@ private List<Bucket> mergeBuckets(Bucket[] candidateClusters, AggregationReduceC
     @Override
     protected AggregatorReducer getLeaderReducer(AggregationReduceContext context, int size) {
         return new AggregatorReducer() {
-
             final LongObjectPagedHashMap<BucketReducer> bucketsReducer = new LongObjectPagedHashMap<>(size, context.bigArrays());
 
             /**
@@ -432,7 +419,7 @@ public int hashCode() {
     @Override
     public boolean equals(Object obj) {
         InternalGeoPointClustering other = (InternalGeoPointClustering) obj;
-        return Objects.equals(requiredSize, other.requiredSize) && Objects.equals(buckets, other.buckets);
+        return (Objects.equals(requiredSize, other.requiredSize) && Objects.equals(buckets, other.buckets));
     }
 
     static class BucketPriorityQueue<A, B extends Bucket> extends ObjectArrayPriorityQueue<A> {

src/yamlRestTest/resources/rest-api-spec/test/GeoPointClusteringAggregation/20_geo_clustering.yml

@@ -124,14 +124,12 @@ setup:
         index: test
         body: {"aggs": { "gc" : { "geo_point_clustering": {"field": "point", "zoom": 1} } } }
 
-
   - match: { hits.total: 15 }
   - length: { aggregations.gc.buckets: 1 }
   - match: { aggregations.gc.buckets.0.doc_count: 15 }
   - match: { aggregations.gc.buckets.0.centroid.lat: 48.8468417795375 }
   - match: { aggregations.gc.buckets.0.centroid.lon: 2.331401154398918 }
 
-
 ---
 
 "Test Zoom 9":
@@ -278,3 +276,73 @@ setup:
 
   - gte: { hits.total: 1 }
   - length: { aggregations.gc.buckets: 1 }
+
+---
+"Test that the cache is working":
+  - do:
+      indices.create:
+        index: test_cache_index
+        body:
+          settings:
+            number_of_shards: 1
+          mappings:
+            "properties":
+              "point":
+                "type": "geo_point"
+
+  - do:
+      index:
+        index: test_cache_index
+        id: 1
+        body: { "point": [2.253588, 48.864682] }
+
+  - do:
+      index:
+        index: test_cache_index
+        id: 2
+        body: { "point": [2.336643, 48.822493] }
+
+  - do:
+      index:
+        index: test_cache_index
+        id: 3
+        body: { "point": [2.438465, 48.84204] }
+
+  - do:
+      indices.refresh:
+        index: test_cache_index
+
+  - do:
+      search:
+        index: test_cache_index
+        request_cache: true
+        body:
+          size: 0
+          aggs:
+            gc:
+              geo_point_clustering:
+                field: point
+                zoom: 1
+
+  - length: { aggregations.gc.buckets: 1 }
+  - match: { aggregations.gc.buckets.0.doc_count: 3 }
+  - match: { aggregations.gc.buckets.0.centroid.lat: 48.84307164698839 }
+  - match: { aggregations.gc.buckets.0.centroid.lon: 2.3428986221551895 }
+
+  # Second strictly identical agg is hitting the cache
+  - do:
+      search:
+        index: test_cache_index
+        request_cache: true
+        body:
+          size: 0
+          aggs:
+            gc:
+              geo_point_clustering:
+                field: point
+                zoom: 1
+
+  - length: { aggregations.gc.buckets: 1 }
+  - match: { aggregations.gc.buckets.0.doc_count: 3 }
+  - match: { aggregations.gc.buckets.0.centroid.lat: 48.84307164698839 }
+  - match: { aggregations.gc.buckets.0.centroid.lon: 2.3428986221551895 }