Integration with Nextcloud Deck: webhook and/or slash

Hello,

I would like to use Mattermost together with Nextcloud Deck (GitHub - nextcloud/deck: 🗂 Kanban-style project & personal management tool for Nextcloud, similar to Trello). The final objective would be to create tasks in Nextcloud Deck by sending a message on Mattermost (assigning the task to a specific person, with a due date, …)

As a first step, I would like to create (from Mattermost) a new card in Nextcloud Deck. There’s an API in Nextcloud Deck (REST API - Nextcloud Deck). On Mattermost side, I understand that I can use either outgoing webhook or slash command.

As I’m a beginner in this field, what do you advise me? Did anybody already tried something similar?

Thanks for your support!