jmehrens
commented
3 days ago The IMAP session properties are in the Angus Mail project. Try setting session property mail.imap.partialfetch=false. If you are using imaps the entry is mail.imaps.partialfetch=false
Describe the bug We are trying to access a local-run Microsoft Exchange Server via IMAP. This leads us to retrieving attachments of incoming mails with cut-off filenames. After enabling Debug logging we can see that jakarta mail is not downloading the entire MIME structure of the e-mail but is utilizing IMAP to fetch information about attachments via the BODYSTRUCTURE call. Apparently, Exchange is too stupid to support RFC-2251 properly, which allows long fields to be split into multiple lines, and favors to return a cut-off filename instead. This was proven with the logs, the response to the BODYSTRUCTURE call contained the clipped filename (parts of the extension were missing due to them being in the next line inside the MIME structure)
Since we know that jakarta mail also supports POP3, and POP3 expects the mail to be parsed locally, is there a way to alter its behavior on IMAP connections to be the same? Our usecase mandates that we are downloading the entire mail including attachments anyways, so parsing MIME locally would both circumvent the idiocy of Exchange and not come at mentionable cost to us transmission-wise.
To Reproduce Steps to reproduce the behavior: Not really reproducible, this occurs on a customer system with some local Microsoft Exchange server of which operations are even outsourced to a sub-contractor...
Expected behavior Jakarta Mail should ignore the fact that we are talking IMAP and request a download of the entire MIME structure for local parsing as it would do for POP3, instead of using IMAP commands for server-side parsing.
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Desktop (please complete the following information): Unknown/Irrelevant
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