feat(messaging): point a sender refusal at the from a send names

products/messaging/backend/facade/contracts.py

@@ -38,6 +38,7 @@ class TransactionalEmailError(Exception):
     """A send the caller has to fix before retrying. `code` is stable for API clients."""
 
     code = "invalid"
+    attr: str | None = None
 
 
 class TemplateNotSendable(TransactionalEmailError):
@@ -102,6 +103,10 @@ class SenderNotVerified(TransactionalEmailError):
     code = "sender_not_verified"
 
 
+class NamedSenderNotVerified(SenderNotVerified):
+    attr = "from"
+
+
 class SenderRequired(TransactionalEmailError):
     code = "sender_required"
 

products/messaging/backend/presentation/views/message_templates.py

@@ -597,7 +597,7 @@ class SendTransactionalEmailResponseSerializer(serializers.Serializer):
     )
 
 
-class TransactionalEmailRejected(exceptions.APIException):
+class TransactionalEmailRejected(exceptions.ValidationError):
     STATUS_BY_CODE = {
         "quota_limited": 429,
         "idempotency_key_in_flight": 409,
@@ -607,12 +607,12 @@ class TransactionalEmailRejected(exceptions.APIException):
         "recipient_suppressed": 422,
         "recipient_unreachable": 422,
     }
-    # The caller has to change the request. Without this the error handler reports a server error.
+    # The caller has to change the request. Without this the error handler types it `validation_error`.
     default_type = "invalid_request"
 
     def __init__(self, error: TransactionalEmailError) -> None:
         self.status_code = self.STATUS_BY_CODE.get(error.code, status.HTTP_400_BAD_REQUEST)
-        super().__init__(detail=str(error), code=error.code)
+        super().__init__(detail={error.attr: [str(error)]} if error.attr else str(error), code=error.code)
 
 
 class TransactionalEmailUnavailable(exceptions.APIException):

products/messaging/backend/services/transactional_email.py

@@ -32,6 +32,7 @@
     InvalidRecipient,
     InvalidRequest,
     MarketingTemplate,
+    NamedSenderNotVerified,
     QueuedEmail,
     QuotaLimited,
     RecipientSuppressed,
@@ -557,7 +558,7 @@ def _code_send_sender(team_id: int, address: str | None) -> dict[str, Any]:
         ) from e
     except TransactionalEmailSenderUnavailable as e:
         if address:
-            raise SenderNotVerified(f"No verified sender in this project can send from `{email}`.") from e
+            raise NamedSenderNotVerified(f"No verified sender in this project can send from `{email}`.") from e
         raise SenderNotVerified("This project has no verified email sender. Verify a sender domain first.") from e
     return {"integrationId": sender_id, "email": email, "name": name}
 

products/messaging/backend/tests/api/test_transactional_email.py

@@ -736,7 +736,11 @@ def test_a_code_send_without_from_and_without_a_default_sends_from(
         if code is None:
             assert json.loads(mock_post.call_args.kwargs["data"])["send"]["from"] == {"integrationId": created[0].id}
         else:
-            assert response.json()["code"] == code
+            assert (response.json()["type"], response.json()["code"], response.json()["attr"]) == (
+                "invalid_request",
+                code,
+                None,
+            )
             mock_post.assert_not_called()
 
     def test_refuses_a_code_send_from_an_unverified_domain(self, mock_post, _flag, capture):
@@ -745,7 +749,11 @@ def test_refuses_a_code_send_from_an_unverified_domain(self, mock_post, _flag, c
         )
 
         assert response.status_code == status.HTTP_400_BAD_REQUEST, response.json()
-        assert response.json()["code"] == "sender_not_verified"
+        assert (response.json()["type"], response.json()["code"], response.json()["attr"]) == (
+            "invalid_request",
+            "sender_not_verified",
+            "from",
+        )
         assert not TransactionalEmailKey.objects.for_team(self.team.id, canonical=True).exists()
         assert capture.call_args.kwargs["properties"]["error_code"] == "sender_not_verified"
         mock_post.assert_not_called()