feature: Update MR reviewer

[zemzale]

Describe the feature or problem you'd like to solve

In GitLab 13.7 there is MR reviewers field https://about.gitlab.com/blog/2020/10/13/merge-request-reviewers/

Currently there is no way how to interact with this from glab.

Propose a Solution

Add a new flag to --reviewers to allow updating that from glab

Additional context

I actually have not found any API documentation about this. Maybe it's missing, but I didn't dig for too long or just missed it.

[profclems]

This feature is relatively new and I believe most self-hosted instances haven't made the upgrade yet.

Also, I don't know if there's any endpoint available to get the reviewers (Let me know if you find any).

The only endpoint quite close is the Project level Rules under Merge Request approvals API, then we use the eligible approvers list.
This will definately come with a lot of limitations.

Do you have any suggestion on what we can do?

[zemzale]

Also, I don't know if there's any endpoint available to get the reviewers (Let me know if you find any).

It's possible from the MR get endpoint it's just not documented. It's basically the same thing as assignees on a different key.
Example :

{
   ...
    "reviewers": [
        {
            "id": 2182404,
            "name": "Alberts Zemzale",
            "username": "zemzale",
            "state": "active",
            "avatar_url": "https://assets.gitlab-static.net/uploads/-/system/user/avatar/2182404/avatar.png",
            "web_url": "https://gitlab.com/zemzale"
        }
    ],
    ...
}

It seems like updating is not yet possible via API https://gitlab.com/gitlab-org/gitlab/-/issues/292714 . The milestone for that is 13.8 so that is a blocker for updating.

Also it doesn't seem like xanzy/go-gitlab has support for reviewer attribute, but I have opend an issue about it xanzy/go-gitlab#1030

[profclems]

It's possible from the MR get endpoint it's just not documented. It's basically the same thing as assignees on a different key.

Seems the reviewers returned are those who have left a review on the MR or those that reviews have been requested from.
I had expected it to return a list of users who are eligible to review, approve or merge the merge request.

I tried this on gitlab-org/gitlab repo:

→ glab api /projects/gitlab-org%2Fgitlab/merge_requests/51578

The response comes with an empty reviewers array because no review has been left on the merge request and no review requested

{
   ...
   "assignees": [
    {
      "id": 1758950,
      "name": "Erick Bajao",
      "username": "iamricecake",
      "state": "active",
      "avatar_url": "https://assets.gitlab-static.net/uploads/-/system/user/avatar/1758950/avatar.png",
      "web_url": "https://gitlab.com/iamricecake"
    }, 
    {
      "id": 4155490,
      "name": "Marcel Amirault",
      "username": "marcel.amirault",
      "state": "active",
      "avatar_url": "https://assets.gitlab-static.net/uploads/-/system/user/avatar/4155490/avatar.png",
      "web_url": "https://gitlab.com/marcel.amirault"
    }
  ],
  "assignee": {
    "id": 1758950,
    "name": "Erick Bajao",
    "username": "iamricecake",
    "state": "active",
    "avatar_url": "https://assets.gitlab-static.net/uploads/-/system/user/avatar/1758950/avatar.png",
    "web_url": "https://gitlab.com/iamricecake"
  },
  "reviewers": [],
  ...
}

[profclems]

This merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/51186 has been reviewed:

→ gl api /projects/gitlab-org%2Fgitlab/merge_requests/51186

{
...
"reviewers": [
    {
      "id": 142752,
      "name": "Gary Holtz",
      "username": "garyh",
      "state": "active",
      "avatar_url": "https://assets.gitlab-static.net/uploads/-/system/user/avatar/142752/avatar.png",
      "web_url": "https://gitlab.com/garyh"
    }, 
    {
      "id": 236961,
      "name": "Marcia Ramos",
      "username": "marcia",
      "state": "active",
      "avatar_url": "https://assets.gitlab-static.net/uploads/-/system/user/avatar/236961/avatar.png",
      "web_url": "https://gitlab.com/marcia"
    }, 
    {
      "id": 1884221,
      "name": "Patrick Bajao",
      "username": "patrickbajao",
      "state": "active",
      "avatar_url": "https://assets.gitlab-static.net/uploads/-/system/user/avatar/1884221/avatar.png",
      "web_url": "https://gitlab.com/patrickbajao"
    }
  ],
...
}

[kousikmitra]

Would like to work on this one if anyone else haven't pick it yet. :)

[zemzale]

@kousikmitra sure thing. Go ahead and just open a PR.