Ruby Forum NGINX > imap proxy patch

Hi list,

My company has a mail storage system (proprietary). It receives email 
via lmtp and customers can get email from imap and pop3. This system 
does not support imap subfolders. For particular reason we need to put a 
imap proxy in front of this system and I choose nginx to do that. But 
now we have a problem, our customers need to have subfolder features.

So I thought about a solution in imap proxy source code, intercept the 
commands and get subfolder creation/access and change data. All imap 
access (webmail/outlook) will use this proxy.

Example,

If one create a parent folder, let it do this, (ex. Sent)

If one request to create a sub-folder (Sent/2007) we change the request 
and create _xxx_Sent_2007 (as parent folder), When client (through 
proxy) will list or access the folder Sent, we intercept the request, 
read the original folder name and change the response to subfolder 
style.

In other words, our sub-folder protocol would be

_xxx_ (prefix)
_xxx_parent-folder_subfolder

It's a little bit comlex, but the big question is, what do you think 
about it.

Do you know any solution that implement any variation of this idea?

Best Regards,
Fernando

On Mon, Aug 18, 2008 at 08:52:39PM -0300, Fernando - Dfcom wrote:

> In other words, our sub-folder protocol would be
> 
> _xxx_ (prefix)
> _xxx_parent-folder_subfolder
> 
> It's a little bit comlex, but the big question is, what do you think about it.
> 
> Do you know any solution that implement any variation of this idea?

This requires parsing all IMAP commands while proxying.
nginx does not support it.

Fernando - Dfcom wrote:
> imap access (webmail/outlook) will use this proxy.
>  
> Example,
>  
> If one create a parent folder, let it do this, (ex. Sent)
>  
> If one request to create a sub-folder (Sent/2007) we change the 
> request and create _xxx_Sent_2007 (as parent folder), When client 
> (through proxy) will list or access the folder Sent, we intercept the 
> request, read the original folder name and change the response to 
> subfolder style.

You can do some funky stuff with namespaces in dovecot, also dovecot has
a reasonable IMAP proxy feature.  Possibly the two bits can be brought
together to achieve what you need?  Otherwise the author accepts paid
work so you might be able to pay for your required feature

Just another avenue you might try...

I guess it's not possible to switch to a new mail server such as
Dovecot/Cyrus then?

Ed W