I need your help to find the trello API(s) to get all the users on a given card:
Does the trello has the API(s) to support this?
BTW, does the trello "@card" mean all the users above?
First, the "@card" notification option will notify every user who is a member of a card. That means every user whose avatar or initials is displayed on the card.
As for your questions about the API, let's go through those one by one:
The card creator
To find the card creator, you'll need to look up the "cardCreate" action using this request:
The "memberCreator" section in the API results for that action will give you the information of the person who created the card
You can find more information about getting card actions via the API here: https://developers.trello.com/v1.0/reference#cardsidactions
The members who are assigned the card
You can find this with the following request:
which is documented here:
The users who are subscribed to the card
Subscriptions are private, so this information isn't available via the API.
The users who have ever commented on the card
To do this, you would first want to use /1/cards/[card ID]/actions?filter=commentCard to get all of the comment actions that have occurred on that card. Then, you could write a script to parse the "memberCreator" information from those results.
The users who have ever been "at" in the comment.
There isn't a way to directly get this information via the API. The closest option would be to use the request described above to get all of the comment actions from a card, and then write a script that would look for a pattern of @ followed by some characters, followed by a space.