wekan/server/publications/activities.js

// We use activities fields at two different places:
// 1. The board sidebar
// 2. The card activity tab
// We use this publication to paginate for these two publications.

Meteor.publish('activities', (kind, id, limit, hideSystem) => {
  check(
    kind,
    Match.Where(x => {
      return ['board', 'card'].indexOf(x) !== -1;
    }),
  );
  check(id, String);
  check(limit, Number);
  check(hideSystem, Boolean);

  const selector = hideSystem
    ? { $and: [{ activityType: 'addComment' }, { [`${kind}Id`]: id }] }
    : { [`${kind}Id`]: id };
  return Activities.find(selector, {
    limit,
    sort: { createdAt: -1 },
  });
});