feat(flags): add GET feature_flags/:id/status for determining flag staleness

posthog/api/feature_flag.py

@@ -56,6 +56,7 @@
 from posthog.models.feedback.survey import Survey
 from posthog.models.group_type_mapping import GroupTypeMapping
 from posthog.models.property import Property
+from posthog.models.feature_flag.flag_status import FeatureFlagStatusChecker, FeatureFlagStatus
 from posthog.queries.base import (
     determine_parsed_date_for_property_matching,
 )
@@ -836,6 +837,20 @@ def all_activity(self, request: request.Request, **kwargs):
 
         return activity_page_response(activity_page, limit, page, request)
 
+    @action(methods=["GET"], detail=True, required_scopes=["feature_flag:read"])
+    def status(self, request: request.Request, **kwargs):
+        feature_flag_id = kwargs["pk"]
+
+        checker = FeatureFlagStatusChecker(
+            feature_flag_id=feature_flag_id,
+        )
+        flag_status, reason = checker.get_status()
+
+        return Response(
+            {"status": flag_status, "reason": reason},
+            status=status.HTTP_404_NOT_FOUND if flag_status == FeatureFlagStatus.UNKNOWN else status.HTTP_200_OK,
+        )
+
     @action(methods=["GET"], detail=True, required_scopes=["activity_log:read"])
     def activity(self, request: request.Request, **kwargs):
         limit = int(request.query_params.get("limit", "10"))