From a073e84379de6ccfe547e00bd882ad1087f65889 Mon Sep 17 00:00:00 2001
From: imedina <igmecas@gmail.com>
Date: Fri, 13 Dec 2024 13:09:44 +0000
Subject: [PATCH] mongodb: fix aggregation regex

---
 .../commons/datastore/mongodb/MongoDBQueryUtils.java       | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/commons-datastore/commons-datastore-mongodb/src/main/java/org/opencb/commons/datastore/mongodb/MongoDBQueryUtils.java b/commons-datastore/commons-datastore-mongodb/src/main/java/org/opencb/commons/datastore/mongodb/MongoDBQueryUtils.java
index a7ad9b80..bd572108 100644
--- a/commons-datastore/commons-datastore-mongodb/src/main/java/org/opencb/commons/datastore/mongodb/MongoDBQueryUtils.java
+++ b/commons-datastore/commons-datastore-mongodb/src/main/java/org/opencb/commons/datastore/mongodb/MongoDBQueryUtils.java
@@ -783,7 +783,12 @@ private static List<Bson> createFacet(Bson query, List<String> facetFields) {
     }
 
     private static Facet getMongoDBFacet(String groupField, Accumulator accumulator, String accumulatorField, List<Double> boundaries) {
-        String accumulatorId = StringUtils.isNotEmpty(accumulatorField) ? "$" + accumulatorField : "$" + groupField;
+        String accumulatorId;
+        if (accumulator == count) {
+            accumulatorId = StringUtils.isNotEmpty(accumulatorField) ? "$" + accumulatorField : "1";
+        } else {
+            accumulatorId = StringUtils.isNotEmpty(accumulatorField) ? "$" + accumulatorField : "$" + groupField;
+        }
 
         Facet facet;
         switch (accumulator) {