### Problem Currently, Public API support is lacking in Merge Train. This means, users cannot automate their workflow via API. Today, users can control via UI, which is manual operation. ### Proposal Public API support for Merge Train. Here are the proposed endpoints. - `GET api/v4/:id/merge_requests/merge_trains` ... Get all merge trains in the project - `GET api/v4/:id/merge_requests/:merge_request_iid/merge_train` ... Get the detail of the merge train - `POST api/v4/:id/merge_requests/:merge_request_iid/merge_train` ... Add a merge request to a train - `DELETE api/v4/:id/merge_requests/:merge_request_iid/merge_train` ... Remove a merge request from a train ### Related - https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/13059