Migrating from offlineimap to mbsync/isync

When I originally set up my email, I can’t say I did enough research with regards to how to pull email from IMAP and store it locally for fast local access. I settled on offlineimap, which seemed to be pretty popular, but it has a few issues:

it’s slow
sometimes it gets stuck fetching mail (a couple of times I noticed days later that there was a hung process and a lockfile that kept new instances from starting)
the current version in still on python2
the author wants to replace it with imapfw (I think this started 5 years ago–and I’m not sure if it has made much progress)

On the other hand, there is a package called isync with the mbsync executable. It doesn’t seem any more actively maintained, but it’s written in C and is a lot faster. So like, mcgrof from the previous blog post, I set out to replace offlineimap with mbsync.

The config file is fairly straightforward, so I’ll roughly outline what it looks like. There weren’t many examples online, so hopefully this will help.

offlineimap:

[general]
accounts = mydomain
pythonfile = ~/.config/offlineimap/helpers.py

[Account mydomain]
localrepository = mydomain-local
remoterepository = mydomain-remote

[Repository mydomain-local]
type = Maildir
localfolders = ~/mail/mydomain

[Repository mydomain-remote]
type = IMAP
remotehost = your.imap.server.name
remoteuser = you@yourdomain.com
remotepasseval = get_pass('tuffmail')
sslcacertfile = /etc/ssl/certs/ca-certificates.crt
ssl = yes

[Account mailmydomain]
localrepository = mailmydomain-local
remoterepository = mailmydomain-remote

mbsync:

# mbsync config

Create Near
SyncState *

# my mail

MaildirStore mydomain-local
Path ~/mail/mydomain/
Inbox ~/mail/mydomain/inbox
SubFolders Verbatim

IMAPStore mydomain-remote
Host your.imap.server.name
User you@yourdomain.com
PassCmd "gpg -dq ~/.password-store/tuffmail.gpg"
SSLType IMAPS
CertificateFile /etc/ssl/certs/ca-certificates.crt

Channel mydomain-channel
Far :mydomain-remote:
Near :mydomain-local:
Patterns INBOX * !Sync*
Create Near

My worse is better get-mail-loop.sh to replace some systemd timers/units:

#!/bin/sh

set -x

while true
do
    date
    mbsync -a
    ~/bin/fetchrss.sh
    notmuchnew
    sleep 5m
done

I moved my old maildir away and had mbsync regenerate it. Then I had notmuch retag everything after mbsync downloaded it all again.

Migrating from offlineimap to mbsync/isync

June 1, 2021