[cristianscheid]

• Related to: Support OCM 1.3 #2386
• Depends on: feat(ocm): support new format of notfication payload server#66049

Summary

This is a prototype for replacing circles custom federation protocol with OCM. It focuses on how circles events propagate between servers. The idea is to send events via OCM notifications (ocm/notifications) instead of using the two existing custom routes (/apps/circles/incoming/ and /apps/circles/event/).

As a first step, this is what was done:

• circles is advertised on /.well-known/ocm as a new resource type/protocol:

$ curl -s https://nextcloud.local/.well-known/ocm | jq
{
  "enabled": true,
  "apiVersion": "1.0-proposal1",
  "version": "1.1.2",
  "endPoint": "https://nextcloud.local/index.php/ocm",
  "publicKey": { ... },
  "provider": "Nextcloud 36.0.0.1",
  "resourceTypes": [
    {
      "name": "file",
      "shareTypes": [
        "user",
        "group"
      ],
      "protocols": {
        "webdav": "/public.php/webdav/"
      }
    },
    {
      "name": "circle",
      "shareTypes": [],
      "protocols": {
        "circles": "/index.php/apps/circles/"
      }
    }
  ],
  [ ... ]
}

• added new config value: federated_teams_ocm
• when federated_teams_ocm is enabled and remote server advertises via OCM discovery both the circles protocol and the notification-sender-domain capability (see feat(ocm): support new format of notfication payload server#66049), circles events are sent as OCM notifications instead of the custom routes:

POST /apps/circles/incoming/ -> POST /ocm/notifications with CIRCLES_BROADCAST_EVENT
POST /apps/circles/event/ -> POST /ocm/notifications with CIRCLES_REQUEST_EVENT

• these routes/events handle circle management (e.g., adding a member, renaming circle)
• CIRCLES_BROADCAST_EVENT is sent by the server hosting the team to all remote servers that have members
  • each remote server applies the event's changes on receipt
• CIRCLES_REQUEST_EVENT is sent by a server with team members to the server hosting the team
  • the host server applies the change locally, then sends a CIRCLES_BROADCAST_EVENT to all remote servers that have members
  • each remote server applies the event's changes on receipt

• existing routes (/apps/circles/incoming/ and /apps/circles/event/ ) are still there, so servers without this change keep working
• remote servers are still registered with occ circles:remote using WebFinger discovery
• federated items (inside lib/FederatedItems) logic was not changed, meaning server still validates/applies change, and broadcasts it through the async loopback
• what changes is how circle events requests travel between servers, using OCM protocol instead of custom protocol (when enabled and remote supports it)

TODO

• add tests
• maybe as a follow up PR, we could do the remote server registration (occ circles:remote <host>) using OCM discovery instead of WebFinger, by checking if remote has it enabled and lists the circle resource type with the circles protocol

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI