add payment_link and banks

apps/core/session_access.py

@@ -0,0 +1,12 @@
+from django.utils import timezone
+
+
+def grant_scoped_session_access(request, grant_key, grant_id, expires_at, *, preserve_expiry=False):
+    """Rotate anonymous session keys; resource grants still validate their own expiry."""
+    session = request.session
+    session.cycle_key()
+    session[grant_key] = grant_id
+    seconds = max(1, int((expires_at - timezone.now()).total_seconds()))
+    if preserve_expiry:
+        seconds = max(session.get_expiry_age(), seconds)
+    session.set_expiry(seconds)