From: Eric Hodel <drbrain@...7.net>
Date: 2009-05-29T06:24:52+09:00
Subject: Re: Net/IMAP and FLAGGED messages

On May 28, 2009, at 10:25, clegault@gmail.com wrote:

> I have been trying to find some example of how to check for the X-
> Priority flag using Net/IMAP in ruby.

X-Priority is not an IMAP flag, it is a message header.  Flags are  
stored separately from message headers and have nothing to do with  
each other.  Note that IMAP has several flags including \Flagged,  
\Deleted, \Draft, etc. and keywords which are arbitrary text.  None of  
these have anything to do with message headers.

> I have tried to do a search for it:
>
> imap.search(["FLAGGED"]).collect

This search will give you messages you have flagged in your email  
client, usually with a little orange flag icon.

You want this search to get messages with the X-Priority header:

imap.search ['HEADER', 'X-Priority', '']

See RFC 3501 section 6.4.4

> And I have tried to do a fetch on a given message to try to find it:
>
> fetch_result = imap.fetch(msgID, ["UID", "FLAGGED"])

There's no "FLAGGED" fetch term.

If you only want to get the X-Priority value, this is sufficient:

BODY[HEADER.FIELDS (X-Priority)]

See RFC 3501 section 6.4.5

Beware bug 1496, as a workaround you can wrap this in  
Net::IMAP::RawData.new if you're fetching more than one item.

http://redmine.ruby-lang.org/issues/show/1496

Also, given that you have the UID already, you can use #zip to match a  
response to its UID.

> I can't find any example of this anywhere, and the docs for Net/IMAP
> just simply say "Flag indicating a message has been flagged for
> special or urgent attention".
>
> Does anyone have some example of how I can retrieve this information?

See the imap_processor gem and the imap_to_rss gem.