Support iMIP invitations from Mail

[miaulalala]

Fixes nextcloud/mail#6803
Fixes #19144
Fixes #22532
To Do:

• Write updated or accepted calendar events to CalDAV
• Tests

Don't do "Fix CANCEL method for emails that are updated from UI (#33008) - the STATUS CANCELLED should also lead to an iMIP message with method CANCEL, not reply" as we're using a systemwide email address which could lead to cancellation email addresses not being processed by other mail clients.

Considerations:

• Extend the CalendarImpl to handle these requests
• Preconditions as specified in the RFC must be met, and the VEVENT that should be written needs to be compared to the original for both ORGANIZER and ATTENDEE
• CANCEL requests must be from the right email address and the right organiser or they shouldn't be processed. (but what if we send them from NC from the system email? Will that work? maybe accepting the system email as a secondary email address as specified in the RFC could work.)

[github-advanced-security]

Found 20 potential problems in the proposed changes. Check the Files changed tab for more details.

[miaulalala]

@st3iny sorry I forgot to tell you: there will be two new endpoints for processing the invitations/responses but you can use them almost the same as the createFromString. I just need a recipient and sender for both to do the security checks as mentioned in the RFC.

[miaulalala]

F*CK YEAH

[ChristophWurst]

Looks good so far!

[github-advanced-security]

Found 15 potential problems in the proposed changes. Check the Files changed tab for more details.

[github-advanced-security]

Found 15 potential problems in the proposed changes. Check the Files changed tab for more details.

[kesselb]

Thank you 👍

Looks good to me. Did a test run with 4 users.

• Organizer Admin
• Local guest User2
• Local guest User3
• External guest with Gmail account

The invitation is properly sent to all 4 guests. External guest with Gmail account accepted the invitation. Response went to Admin's inbox and IMipService updated the attendance for Admin, User2 and User 3 🥳 🥳

Updating the calendar attendance may take a while. On mailbox refresh the message is flagged as imip message and processed by a background job later. We recommend to run the background job every 5 minutes. I understand the technical reasoning yet it's not ideal.

Thunderbird shows a hint when a message contains an imip reply/cancel and if the data is already processed. I believe that would be a nice enhancement.

Run into the following "bug" while testing this PR. It seems unrelated and should not block it:

I accepted the invitation for User2 via Calendar. The vcard is updated properly but the imip processing does not work. Only my (the copy in my personal calendar) is updated. Organizer and other attendees don't see the updated attendance. Looked at it with Xdebug for a second but could not figure it out. The imip logic is executed however it does not emit an imip message. A starting point for further debugging could be the InviteResponseController as it works over there.

[miaulalala]

I accepted the invitation for User2 via Calendar. The vcard is updated properly but the imip processing does not work. Only my (the copy in my personal calendar) is updated. Organizer and other attendees don't see the updated attendance. Looked at it with Xdebug for a second but could not figure it out. The imip logic is executed however it does not emit an imip message. A starting point for further debugging could be the InviteResponseController as it works over there.

Sorry I think I "steh auf der Leitung":

So you accepted an Invitation from Admin to User2 via Calendar, and the calendar doesn't distribute the changes to the other Attendees/ Guests?

This sounds like a bug I've seen before... @st3iny how did you implement the Accept/Decline from Calendar? Does that do a PROPPATCH?

[st3iny]

This sounds like a bug I've seen before... @st3iny how did you implement the Accept/Decline from Calendar? Does that do a PROPPATCH?

I just set the participation status of the attendee on the local copy and then save the ics again (via PUT). The rest is handled by Sabre and wasn't touched by me.

[miaulalala]

This sounds like a bug I've seen before... @st3iny how did you implement the Accept/Decline from Calendar? Does that do a PROPPATCH?

I just set the participation status of the attendee on the local copy and then save the ics again (via PUT). The rest is handled by Sabre and wasn't touched by me.

It was the plus sign in Daniel's test email that makes it break 🕵️

[Luncheon3462]

@ChristophWurst @miaulalala @st3iny, please help get this fixed. When Office 365 sends calendar invitations, the snappymail nextcloud app by @the-djmaze handles them perfectly. They appear in the email message and can be added to a nextcloud calendar with one-click. Maybe this code that @the-djmaze mentioned will work? https://github.com/the-djmaze/snappymail/blob/fffc04499875531bd3dd626d01baaf7a86452cd3/plugins/nextcloud/js/message.js#L111-L179

[miaulalala]

@ChristophWurst @miaulalala @st3iny, please help get this fixed. When Office 365 sends calendar invitations, the snappymail nextcloud app by @the-djmaze handles them perfectly. They appear in the email message and can be added to a nextcloud calendar with one-click. Maybe this code that @the-djmaze mentioned will work? the-djmaze/snappymail@fffc044/plugins/nextcloud/js/message.js#L111-L179

Hi Luncheon, please stop mass tagging and commenting on old tickets and PRs. You're creating a lot of noise, not just for us but also the-djmaze. That isn't cool.

If you have a feature request or bug to report, use the new issue button in the repository AFTER you've searched if an issue already exists. If it does, please refrain from commenting unless you have logs / debugging steps to add, and add your reaction to the ticket instead. If you're a developer, you can also contribute your own PRs and we will work with you to get them merged.

Cheers.