datafire/distribution/src/util/schedule.js

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"use strict";

var schedule = module.exports = {};

schedule.parse = function (sched) {
  var cronMatch = sched.match(/^cron\((.*)\)$/);
  if (cronMatch) return cronMatch[1];
  var rateMatch = sched.match(/^rate\((\d+)\s+(\w+)\)/);
  if (!rateMatch) throw new Error("Could not parse schedule: " + sched);
  var unit = rateMatch[2];
  var num = +rateMatch[1];
  return schedule.cronRate(num, unit);
};

var UNITS = ['minute', 'hour', 'day', 'month', 'dayOfWeek', 'year'];

schedule.cronRate = function (num, unit) {
  if (/s$/.test(unit)) unit = unit.substring(0, unit.length - 1);
  var cron = '';
  var set = false;
  UNITS.forEach(function (nextUnit) {
    if (cron) cron += ' ';
    if (nextUnit === unit) {
      cron += '*/' + num;
      set = true;
    } else if (!set) {
      cron += '0';
    } else {
      cron += '*';
    }
  });
  return cron;
};

schedule.cronToNodeCron = function (cron) {
  var times = cron.split(/\s+/);
  if (times.length === 6) {
    var year = times.pop(); // remove year
    if (year !== '*') throw new Error("Cron expressions with six pieces should use '*' for the year");
  }
  if (times.length !== 5) {
    throw new Error("Cron expressions should have exactly five pieces");
  }
  times.unshift('0'); // add seconds;
  return times.join(' ');
};