Link Jira issue state with external service task system


I’m currently working on a plugin which needs to link a Jira issue to an external service which have its own task system. A transition in the task should change issue state, and the other way around should work too. I’m working on the latter.

This external service have three main states for its tasks: “Todo”, “In progress”, “Done”.

I’ve set up a webhook to get transition events from Jira, but I don’t find a way to know in what category the new issue state is in (here, “categories” means the colors of the workflow states). Since it doesn’t seem possible, I tried something else.

Via the REST API, I tried to get all the data I needed to let the user map the workflow states to task states, but I can’t find a way to get either the active workflow scheme of a projet, nor the available states of a workflow.

Is this impossble to achieve with atlassian-connect-express?
Or is a workaround possible?

Thanks in advance,
Quentin Bazin