diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index c178ddf070..c031903b1a 100644
--- a/synapse/api/constants.py
+++ b/synapse/api/constants.py
@@ -269,3 +269,14 @@ class PublicRoomsFilterFields:
GENERIC_SEARCH_TERM: Final = "generic_search_term"
ROOM_TYPES: Final = "room_types"
+
+
+class ApprovalNoticeMedium:
+ """Identifier for the medium this server will use to serve notice of approval for a
+ specific user's registration.
+
+ As defined in https://github.com/matrix-org/matrix-spec-proposals/blob/babolivier/m_not_approved/proposals/3866-user-not-approved-error.md
+ """
+
+ NONE = "org.matrix.msc3866.none"
+ EMAIL = "org.matrix.msc3866.email"
diff --git a/synapse/api/errors.py b/synapse/api/errors.py
index 1c6b53aa24..c606207569 100644
--- a/synapse/api/errors.py
+++ b/synapse/api/errors.py
@@ -106,6 +106,8 @@ class Codes(str, Enum):
# Part of MSC3895.
UNABLE_DUE_TO_PARTIAL_STATE = "ORG.MATRIX.MSC3895_UNABLE_DUE_TO_PARTIAL_STATE"
+ USER_AWAITING_APPROVAL = "ORG.MATRIX.MSC3866_USER_AWAITING_APPROVAL"
+
class CodeMessageException(RuntimeError):
"""An exception with integer code and message string attributes.
@@ -566,6 +568,20 @@ class UnredactedContentDeletedError(SynapseError):
return cs_error(self.msg, self.errcode, **extra)
+class NotApprovedError(SynapseError):
+ def __init__(
+ self,
+ msg: str,
+ approval_notice_medium: str,
+ ):
+ super().__init__(
+ code=403,
+ msg=msg,
+ errcode=Codes.USER_AWAITING_APPROVAL,
+ additional_fields={"approval_notice_medium": approval_notice_medium},
+ )
+
+
def cs_error(msg: str, code: str = Codes.UNKNOWN, **kwargs: Any) -> "JsonDict":
"""Utility method for constructing an error response for client-server
interactions.
|