Repository navigation
Expose message ID list from ReferencesHeader #148797
Description
Feature or enhancement
Proposal:
When sending, parsing or validating mails which are replies to other mails it is necessary to access the message IDs from the In-Reply-To and References headers. These, however, are currently not exposed.
# Example use case
if "In-Reply-To" in msg and "References" in msg:
[in_reply_to_token] = msg["In-Reply-To"].message_ids
[*_, most_recent_reference_token] = msg["References"].message_ids
if in_reply_to_token.value != most_recent_reference_token.value:
raise ValueError(f"Error: References list end must match In-Reply-To message ID")A workaround is to access the private _parse_tree property which does expose the message_id, though like any private property that should obviously be avoided. This is comparable to AddressHeader which already exposes addresses.
Has this already been discussed elsewhere?
This is a minor feature, which does not need previous discussion elsewhere
Links to previous discussion of this feature:
No response
Activity
picnixz commentedon Apr 20, 2026
cc @bitdancer
bitdancer commentedon Apr 20, 2026
Agreed that this would be a nice feature to add. Could have done it when we added the header type, but we were focused on fixing the incorrect encoding problem ;)
Abdur-rahmaanJ commentedon May 19, 2026
Having a go at it at the CPython PyCon Sprints
septatrix commentedon Oct 12, 2026
I assume nothing came of that?^^
Abdur-rahmaanJ commentedon Oct 12, 2026
@septatrix Sorry forgot to update, went to the Android side of things.