Fixed #12990, Refs #27694 -- Added JSONField model field.

Thanks to Adam Johnson, Carlton Gibson, Mariusz Felisiak, and Raphael
Michel for mentoring this Google Summer of Code 2019 project and
everyone else who helped with the patch.

Special thanks to Mads Jensen, Nick Pope, and Simon Charette for
extensive reviews.

Co-authored-by: Mariusz Felisiak <felisiak.mariusz@gmail.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/django/db/backends/mysql/features.py b/django/db/backends/mysql/features.py
index 8a2a64c5e4..faa84f7d7c 100644
--- a/django/db/backends/mysql/features.py
+++ b/django/db/backends/mysql/features.py
@@ -160,3 +160,15 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     def supports_default_in_lead_lag(self):
         # To be added in https://jira.mariadb.org/browse/MDEV-12981.
         return not self.connection.mysql_is_mariadb
+
+    @cached_property
+    def supports_json_field(self):
+        if self.connection.mysql_is_mariadb:
+            return self.connection.mysql_version >= (10, 2, 7)
+        return self.connection.mysql_version >= (5, 7, 8)
+
+    @cached_property
+    def can_introspect_json_field(self):
+        if self.connection.mysql_is_mariadb:
+            return self.supports_json_field and self.can_introspect_check_constraints
+        return self.supports_json_field