A script to post the name of a team member to a slack web hook once a week.

team-member-by-week.js

(async function () {
  var webHookUrl = "https://hooks.slack.com/triggers/a/b/c";

  // credits chatgpt
  function isoWeek(date) {
    // copy date so don't modify original
    date = new Date(date);

    // set to nearest thursday (current date + 4 - current day) % 7
    date.setUTCDate(date.getUTCDate() + 4 - (date.getUTCDay() || 7));

    // get first day of year
    var yearStart = new Date(Date.UTC(date.getUTCFullYear(), 0, 1));

    // calculate full weeks to nearest thursday
    var week = Math.ceil(((date - yearStart) / 86400000 + 1) / 7);

    return week;
  }

  var team = [];

  var memberByWeek = [...Array(52).keys()]
    .map((n) => n + 1)
    .map((week) => team[(week - 1) % team.length]);

  var member = memberByWeek[isoWeek(new Date())];

  await fetch(webHookUrl, {
    method: "POST",
    body: JSON.stringify({ member }),
    headers: {
      "content-type": "application/json",
    },
  });
})();