Fixed #26327 -- Added JsonAgg to contrib.postgres.

Thanks Tim Graham for review.

1 files changed, 12 insertions, 1 deletions

diff --git a/django/contrib/postgres/aggregates/general.py b/django/contrib/postgres/aggregates/general.py
index 6ff6727bd4..5d420505eb 100644
--- a/django/contrib/postgres/aggregates/general.py
+++ b/django/contrib/postgres/aggregates/general.py
@@ -1,7 +1,8 @@
+from django.contrib.postgres.fields import JSONField
 from django.db.models.aggregates import Aggregate
 
 __all__ = [
-    'ArrayAgg', 'BitAnd', 'BitOr', 'BoolAnd', 'BoolOr', 'StringAgg',
+    'ArrayAgg', 'BitAnd', 'BitOr', 'BoolAnd', 'BoolOr', 'JsonAgg', 'StringAgg',
 ]
 
 
@@ -30,6 +31,16 @@ class BoolOr(Aggregate):
     function = 'BOOL_OR'
 
 
+class JsonAgg(Aggregate):
+    function = 'JSONB_AGG'
+    _output_field = JSONField()
+
+    def convert_value(self, value, expression, connection, context):
+        if not value:
+            return []
+        return value
+
+
 class StringAgg(Aggregate):
     function = 'STRING_AGG'
     template = "%(function)s(%(distinct)s%(expressions)s, '%(delimiter)s')"