Three IMAP connection leaks were recently fixed via try/finally
(#1325, #1330, #1423). This commit applies the same pattern to the
remaining callsites that still used inline logout-only cleanup.
routes/email_helpers.py:
- _fetch_sender_thread_context: conn was uninitialized when the outer
try/except returned early on connect failure, causing the finally
block to crash on conn.close()/conn.logout(). Merged the two
separate try blocks into one and added conn=None guard.
- _pre_retrieve_context: ctx_conn.logout() was inside the loop body
with no finally, so any exception in the folder/search loop leaked
the socket. Moved cleanup into a finally block with ctx_conn=None
guard.
mcp_servers/email_server.py:
- _list_emails: multiple inline conn.logout() calls on early-return
paths; exception between them leaked the socket. Wrapped in
try/finally.
- _read_email: same pattern — four separate logout() calls replaced
by a single finally block.
- _reply_to_email: logout() called before the error check, so an
exception in conn.select() leaked the socket. Wrapped in
try/finally.
- _download_attachment: same pattern as _reply_to_email.
Also adds tests/test_imap_leak_fixes.py with 9 regression tests (one
per function/failure-mode) that monkeypatch _imap_connect and assert
conn.logout() is called exactly once even when IMAP operations raise.
read_email, reply_to_email and download_attachment fetched the full message with
the legacy bare RFC822 item (UID FETCH <uid> (RFC822)). iCloud's IMAP server
silently ignores it — the fetch returns status OK but only (UID <uid>) with no
body tuple, so the parse reports 'Email not found with UID' even though the
message exists and list_emails (which uses RFC822.HEADER) shows it. Gmail honours
(RFC822), which is why it only reproduced on iCloud.
Switch the three full-message fetches to (BODY.PEEK[]), which iCloud and Gmail
both honour and which doesn't set \Seen. Response shape is unchanged (raw bytes
still at msg_data[0][1]), so parsing is unaffected; the RFC822.HEADER (listing)
and (UID) probe fetches are left as-is.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Lucas Daniel