Within Rocket.Chat, without starting additional apps, enable a user of Nextcloud to select files from his Nextcloud server/account and upload (or reference) them within Rocket.Chat channels.
Need to build a minimal skeleton that eliminates the technical hurdles, and allow additional contributors to extend it into a full feature.
From Frank (CEO NextCloud):
Information about the Nextcloud APIs that can be used:
Login Flow to get the app to password for authentication: https://docs.nextcloud.com/server/13/developermanual/clientapis/LoginFlow/index.html
WebDav. This is mostly standard WebDAV to browse the files: https://docs.nextcloud.com/server/13/developermanual/clientapis/WebDAV/index.html
Sharing. This is the API to get a sharing link for any file https://docs.nextcloud.com/server/13/developer_manual/core/ocs-share-api.html
Federated Sharing. This is our current Federation API but work in progress. https://lukasreschke.github.io/OpenCloudMeshSpecification/#federated-sharing