cron-time-generator2/helpers.ts

Cron Time Expression Generator

const DaysDictionary: Record<string, number> = {
  sun: 0,
  mon: 1,
  tue: 2,
  wed: 3,
  thu: 4,
  fri: 5,
  sat: 6,
  sunday: 0,
  monday: 1,
  tuesday: 2,
  wednesday: 3,
  thursday: 4,
  friday: 5,
  saturday: 6,
};

export default {
  /**
   * @param {number} position
   * @param {*} value
   * @param {string} str
   */
  spliceIntoPosition(
    position: number,
    value: string,
    str: string | undefined = undefined
  ): string {
    if (str === undefined) {
      str = this.minute();
    }

    let def = str.split(" ");
    def.splice(position, 1, value);
    return def.join(" ");
  },

  minute(): string {
    return "* * * * *";
  },

  hour(): string {
    return "0 * * * *";
  },

  day(hourOfTheDay: number = 0, minuteOfTheHour: number = 0): string {
    return `${minuteOfTheHour} ${hourOfTheDay} * * *`;
  },

  /**
   * Get the integer representation of day string.
   * @param {string|number} day
   * @return {number}
   * @example
   *  Helpers.dayToInt('sunday') // 0
   *  Helpers.dayToInt('monday') // 1
   */
  dayToInt(day: number | string): number {
    if (typeof day === "number") return day;
    day = day.trim().toLowerCase();

    const value = DaysDictionary[day];

    if (!value) throw Error(`Day: "${day}" is not a valid day.`);

    return value;
  },

  /**
   * Get the integer representation of multiple day strings.
   * @param days
   */
  daysToIntegers(days: (string | number)[]): number[] {
    const newDays: number[] = [];
    for (const day of days) {
      if (typeof day === "string") {
        newDays.push(this.dayToInt(day));
      } else {
        newDays.push(day);
      }
    }

    return newDays;
  },

  /**
   * Checks of startDay and endDay follows calendar sequence.
   * else throws error.
   * @param startDay
   * @param endDay
   */
  validateStartToEndDay(startDay: number, endDay: number) {
    if (startDay > endDay)
      throw Error(
        "startDay must come before endDay following normal calendar sequence."
      );
  },
};