MDTG

This package converts Date objects to military date time and vice versa.

Install

npm install mdtg

Usage

import { formatMDTG, parseMDTG } from "mdtg";

const date = new Date(Date.UTC(2024, 7, 12, 11, 55, 30));

formatMDTG(date, { form: "short" });      // "121155Z"
formatMDTG(date, { form: "standard" });   // "121155Zaug24"
formatMDTG(date);                         // "12115530Zaug24" (extended by default)

// A is UTC+1, so local time is one hour ahead of UTC.
const value = formatMDTG(date, { timezone: "A" }); // "12125530Aaug24"
parseMDTG(value).toISOString();                       // "2024-08-12T11:55:30.000Z"

parseMDTG("121155Zaug24").toISOString(); // "2024-08-12T11:55:00.000Z"
parseMDTG("121155Z");                    // month and year are current UTC month/year

API

formatMDTG(date, options)

Converts a valid Date to a date-time group. date defaults to the current date. options.form is "short", "standard", or "extended" (the default). options.timezone accepts the NATO time-zone letters A through Z; lowercase letters are accepted and unknown values default to Z. The timezone letter determines the displayed local time; parsing converts it back to a UTC Date.

formatMDTG(new Date(Date.UTC(2024, 7, 12, 11, 55, 30)), {
  form: "extended",
  timezone: "A",
});
// "12125530Aaug24"

parseMDTG(value)

Parses short (121155Z), standard (121155Zaug24), and extended (12115530Zaug24) formats into a Date. Short values use the current UTC month and year and have no seconds. Years are interpreted as 2000 through 2099.

import { parseMDTG } from "mdtg";

parseMDTG("121155Zaug24").toISOString();   // "2024-08-12T11:55:00.000Z"
parseMDTG("12115530Zaug24").toISOString(); // "2024-08-12T11:55:30.000Z"
parseMDTG("12125530Aaug24").toISOString(); // "2024-08-12T11:55:30.000Z"

parseMDTG("121155Z"); // uses the current UTC month and year

Invalid calendar dates and times, such as 310224Zfeb24 or 126155Z, throw a RangeError. Other invalid values throw an Error.

Format checks

isShortFormat, isStandardFormat, and isExtendedFormat check whether a string matches the structure of the corresponding format. isMDTG checks whether a string matches any of the three formats.

import {
  isShortFormat,
  isStandardFormat,
  isExtendedFormat,
  isMDTG,
} from "mdtg";

isShortFormat("121155Z");          // true
isStandardFormat("121155Zaug24"); // true
isExtendedFormat("12115530Zaug24"); // true
isMDTG("121155Zaug24");      // true
isMDTG("invalid");           // false