habitica/migrations/groups/create-group.js

import { model as Group } from '../../website/server/models/group';
import { model as User } from '../../website/server/models/user';

// @TODO: this should probably be a GroupManager library method
async function createGroup (name, privacy, type, leaderId) {
  let user = await User.findOne({_id: leaderId});

  let group = new Group({
    name,
    privacy,
    type,
  });

  group.leader = user._id;
  user.guilds.push(group._id);

  return Promise.all([group.save(), user.save()]);
}

module.exports = async function groupCreator () {
  let name = process.argv[2];
  let privacy = process.argv[3];
  let type = process.argv[4];
  let leaderId  = process.argv[5];

  await createGroup(name, privacy, type, leaderId);
};