Re: fetchmail to an IMAP proxy with filtering?

On 16/6/26 09:58, Jay Faulkner wrote:
> I've needed to improve my email situation for a while. Right now, I 
> have my personal mail hosted on Office 365. I just IMAP it off into 
> Thunderbird on my desktop, laptop, and phone. Two major problems with 
> that setup right now: first, I keep getting rate-limited on IMAP from 
> Office 365. Secondly, the filtering provided by the service is very 
> limited and doesn't always work great.
>
> So I was thinking, it's got to be possible for me to setup a kind of 
> client-proxy, right?
>
> I'm thinking:
> - Fetch 100% of the messages/content/etc from upstream IMAP to my server
> - Use [local filtering mechanism of some kind] to filter them into
>   trash or specific folders. I'll note: spam filtering is handled pretty
>   well by Office365, so that's outta scope. This is more about putting
>   mailing lists in their proper folders reliably, and regaining some
>   power over things like github and gerrit e-mail notifications.
> - Host an IMAP server that I can then point at this filtered, downloaded
>   message content and feed it all to as many devices as I want without
>   fear of rate limiting.
>
> A couple of extra requirements I have:
> - Any sorting done locally (e.g. filtering mailing list posts to a
>   folder) needs to *also* happen on the upstream origin IMAP server. I
>   want it to remain the source of truth and for webmail to still be
>   useful.
> - Ideally I can handle multiple accounts *with multiple logins*
>   transparently. Imagine right now I have a Thunderbird account pointed
>   to [email protected] at outlook.office365.com -- I want to just be
>   able to change that to personal_email_tld (or similar -- not a shared
>   login account) and have it transition over smoothly. If that's not
>   possible, I still want a solution where 1 login = 1 email account,
>   and not one where top-level folders map to specific accounts.
>
> I'm asking on the list because... well, first of all I've never done 
> this, but also, I just have no idea of the 2026 state of the art of 
> these tools. I'm hoping someone can help. I've worked with email a lot 
> generally, but all on the server/hosting side and all 15+ years ago so 
> I know the protocols just maybe not the best tool choices.
>
> Any help you can provide is appreciated!
>
> Thanks,
> JayF
>
> P.S. I know there will be folks saying "change hosting". I'm not going 
> to do that; as that would be disruptive to other family members on my 
> domain. Either way, if I solve this myself the hosting becomes less of 
> a concern generally.
>
>
Google "gentoo email gateway" for ideas.  I gave up on fetchmail a 
couple of years ago due to out of date upstream ISP ssl requirements and 
moved to "getmail" (which I was able to modify the source for my use 
case) which feeds to postfix and useing procmail/spamassisin and 
amavis-ng for filtering.

Hav e fun!

BillK