Using Offlineimap with Gnus

As I rely more and more on my 3G connection, its high latency made my Gnus experience more more unbearable. I wanted to keep using IMAP in order to use multiple clients while on the go, so I settled on using OfflineIMAP. OfflineIMAP will download all your mail and keep it in Maildir format any changes Gnus makes will be synchronized back to GMail and as a bonus you get a backup of all your emails. Even though both OfflineIMAP and Gnus has been around for years they still don't play well with each other, Gnus uses its own flags instead of using standard Maildir flags so your changes aren't synchronized back to GMail, someone complained about this 6 years ago but sadly nothing has changed. There is still hope though, using the script he posted with OfflineIMAP's pre/post hooks we can sync Gnus flags to Maildir and vice versa.

ui = Noninteractive.Basic
accounts = nakkaya

[Account nakkaya]
localrepository = nakkayaLocal
remoterepository = nakkayaRemote
autorefresh = 1

presynchook = ~/Projects/scripts/sync_nnmaildir -g
postsynchook = ~/Projects/scripts/sync_nnmaildir -m

[Repository nakkayaLocal]
type = Maildir
localfolders = ~/Documents/mail/

[Repository nakkayaRemote]
type = Gmail
remoteuser = [email protected]
remotepass = super_secret_password
holdconnectionopen = true
keepalive = 60

#Setting realdelete = yes will Really Delete email from the server.
#Otherwise "deleting" a message will just remove any labels and 
#retain the message in the All Mail folder.
realdelete = no

Save this snippet as ".offlineimaprc", change remote repository type to IMAP if you need to use this with some other IMAP server. Only trick here is to sync Gnus flags to Maildir before IMAP sync and sync Maildir flags to Gnus flags after IMAP sync. Now run offlineimap while it synchronizes your messages open your ~/.gnus set your select method to use nnmaildir,

(setq gnus-select-method 
      '(nnmaildir "GMail" 
                  (directory "~/Documents/mail/")
                  (directory-files nnheader-directory-files-safe) 
                  (get-new-mail nil)))

(define-key gnus-group-mode-map (kbd "vo")
  '(lambda ()
     (shell-command "offlineimap&" "*offlineimap*" nil)))

Now start Gnus, press ^ (gnus-group-enter-server-mode), open nnimap:GMail, for each folder press u (gnus-browse-unsubscribe-current-group) to toggle the subscription status until you’re subscribed to the group. Then it should show up on the group screen (M-x gnus). This also adds a new key binding to the group buffer, typing "vo" will start OfflineIMAP.

For sending email using GMail, you need to install gnutls package, then add the following to your .gnus,

(load "tls")
(setq send-mail-function 'smtpmail-send-it
      message-send-mail-function 'smtpmail-send-it
      starttls-use-gnutls t
      starttls-gnutls-program "/opt/local/bin/gnutls-cli"
      starttls-extra-arguments nil      
      '(("" 587 nil nil))
      ;; smtpmail-auth-credentials
      ;;'(("" 587 "[email protected]" "pass" ))
      '(("" 587 "[email protected]" nil))
      smtpmail-default-smtp-server ""
      smtpmail-smtp-server ""
      smtpmail-smtp-service 587
      smtpmail-debug-info t
      smtpmail-local-domain "")

You also need a .netrc file in your home directory with the following content,

machine login [email protected] password pass port 587

With this setup you should be able to send and receive email. This setup isn't perfect, an OS X bug makes OfflineIMAP crash while trying to download large emails, also it does crash every 10 hours or so but I can live with that, on the plus side it makes Gnus blazing fast.