ActiveSync / Push Notifications for Cloudron Mailserver

[girish]

I had to look up the difference between IMAP IDLE and ActiveSync. Per https://www.aspnix.com/kb/sales-kb/imap-idle-vs-activesync/, "While IMAP IDLE provides real-time notifications to your client, it differs from ActiveSync in many ways. IMAP IDLE is an extension of the IMAP protocol (as described here) and IMAP being a message protocol, it handles only email. ActiveSync (as described here) handles email, calendar, contacts, notes and tasks, and syncs them across all of your clients (that support ActiveSync, including devices)."

[jdaviescoates]

@girish I also note that it adds:

"IMAP IDLE can also only generally receive notifications for the folder you currently have selected / viewing. ActiveSync does not have this limitation and receives real-time notifications for all folders."

[jimcavoli]

I've been looking at packaging EAS support broadly through the excellent Kopano-affiliated Z-Push - https://z-push.org - before. I'm just not sure if that would be more useful for the box generally, as a standalone, or as an additional component of some of the webmail app(s).

[girish]

IIRC, @nebulon tried integrating z-push into mail server or SOGo a long time ago, I don't recall entirely. @nebulon do you remember?

[girish]

Don't mind me. The history of that task is at https://git.cloudron.io/cloudron/sogo-app/-/issues/4 . I have to look closer to understand whether it makes sense to integrate ActiveSync in SOGo or in the mail server itself. It looks like it belongs in SOGo but I am not 100% sure.

[jimcavoli]

@girish I tend to agree for that particular app's packaging, though for folks using other solutions for calendar/contacts or who want a more arbitrary mapping, perhaps a freestanding packaging would still make sense, just automating the setup for the Cloudron mail server bit?

[girish]

@jimcavoli How would that work? The z-push server can pull in data from an arbitrary caldav/cardav/imap ?

(I am not an expert on this, so excuse my basic questions)

[jimcavoli]

@girish It's actually pretty slick. Z-Push supports multiple backends for each of the major components, but there's also BackendCombined which allows you to use any of the others (IMAP/CardDav/CalDAV/LDAP/Kopano/MailDir/SQL/more - full list at https://github.com/Z-Hub/Z-Push/tree/develop/src/backend) in combination to serve all the various resources supported.

[girish]

@jimcavoli Very nice, open to have this is as a separate app, if it's easy to package.

[jimcavoli]

@girish Yeah, fairly. All traditional PHP. Doesn't have any admin interface or whatever - designed to be configured in the PHP files. I'll see about throwing something together - should we keep that discussion here for now?

[girish]

@jimcavoli Just to confirm. You think it's a better idea to put this as a separate app than to integrate into mail server, correct? (I think so too from my understanding of how this works with other apps, but want to confirm). If so, let's create a z-push app request and let's continue there. We can probably close this thread.

[jimcavoli]

@girish Yeah, at this point in time. At least if we change our minds from there, it's easy enough to change up later. Created https://forum.cloudron.io/topic/4311/z-push and added it to my personal list

[fbartels]

@girish you could compare Z-Push to a webmail client, but instead of using your webbrowser you use an activesync client to open it.

So treating it like the other webmail interfaces would make sense

[CBCUN]

Hello,
when ist the Z-Push App available? Do you have a Roadmap for this?

Greetings Chris

[crazybrad]

@girish Did Z-Push ever make the final cut for the App Store? Since Zopano stopped supporting this, a new maintainer has emerged (https://kopano.com/blog/z-push-has-a-new-home-and-a-new-maintainer/) and Z-Push appears to have been updated to PHP8+ which is encouraging. @fbartels In searching for z-push I even found an old docker repo you were playing with 9 years ago! This could be a very powerful option for Cloudron email with ActiveSync as an alternative to Exchange/O365. Any interest in pursuing this?

[girish]

We haven't explorer further. I did quickly check if the packages are still there, but atleast on Ubuntu 23, it's gone.

$ apt search z-push
Sorting... Done
Full Text Search... Done

$ apt search z-push-backend-imap
Sorting... Done
Full Text Search... Done

[fbartels]

@crazybrad said in ActiveSync / Push Notifications for Cloudron Mailserver:

n searching for z-push I even found an old docker repo you were playing with 9 years ago

If you look into what you call Zopano, then you will find my name in a lot more places, since to this day Kopano is still my employer

The diff backend used in Z-Push for imap mailboxes is not very efficient, but as long as its only a couple devices it should work. The Kopano backend of Z-Push scales better, but also has its limitations.

The reason for retiring the old project is that we have moved over to a different architecture with a fresh and better scaleable implementation of ActiveSync. If you look into a full Exchange replacement, then https://kopano.com/products/cloud/ may be interesting to you.

[crazybrad]

@fbartels Thanks for the reference and transparency. Kopano Cloud looks interesting and we will consider it for future projects. @girish Thank you for revisiting this.

[crazybrad]

@girish Seems like the package dependencies are all PHP related (php php-cli php-soap php-mbstring php-imap libawl-php php-curl php-xml php-ldap). I searched on one of my Ubuntu 22.04 LTS instances and all packages were available. I don't have Ubuntu 23 so I can't check that version specifically. Given these are fairly standard libs I would hope they will be available in subsequent Ubuntu releases (23+). FYI, installation details are here for Ubuntu 22.04: https://github.com/Z-Hub/Z-Push/wiki/Installation#Z-Push-on-Ubuntu-2204.