Help Wanted: Document how to use message attachments with incoming webhooks

[mickmister]

More context here mattermost/mattermost#21036 (comment)

[neflyte]

Where should this information live? The linked issue says that message attachments aren't just for plugins and should be more global. We should probably have more discussion around how to handle this.

[mickmister]

@neflyte Yes it seems "Plugins" is currently being used as an umbrella section, with things that are not exclusively related to plugins, namely interactive messages in this case. https://developers.mattermost.com/integrate/getting-started. Maybe we can add a new section Interactivity for "interactive messages" and "interactive dialogs".

There are also message attachments in general that are currently described in https://developers.mattermost.com/integrate/reference/message-attachments. Maybe we just need to say in the webhooks section that these attachments are supported, just as they are in the posts API.

[neflyte]

It seems that "message attachments" apply to pretty much everything, potentially in slightly different ways. It think it would be worth attempting to consolidate that information into once place outside of webhooks/slash commands/apps/plugins. I'll add a card to my board for that. 🙂

https://community.mattermost.com/boards/team/rcgiyftm7jyrxnma1osd8zswby/bbft5ccthufy1fcgdrz8ory7bga/vcfirybf6dtbu5b833e4dkhxt5a/cj6d9odmqb7rc8jrys178zwanky