fecha

What is fecha?

The 'fecha' npm package is a lightweight JavaScript library for parsing, formatting, and manipulating dates. It provides a simple and flexible API for handling date and time operations.

What are fecha's main functionalities?

Date Formatting

This feature allows you to format JavaScript Date objects into strings using various format patterns. The example formats the current date into 'YYYY-MM-DD' format.

const fecha = require('fecha');
const formattedDate = fecha.format(new Date(), 'YYYY-MM-DD');
console.log(formattedDate); // Outputs: 2023-10-05

Date Parsing

This feature allows you to parse date strings into JavaScript Date objects using specified format patterns. The example parses the string '2023-10-05' into a Date object.

const fecha = require('fecha');
const parsedDate = fecha.parse('2023-10-05', 'YYYY-MM-DD');
console.log(parsedDate); // Outputs: Thu Oct 05 2023 00:00:00 GMT+0000 (Coordinated Universal Time)

Custom Formatting Tokens

This feature allows you to define custom formatting tokens for date formatting. The example defines a custom token 'custom' for time formatting and uses it to format the current time.

const fecha = require('fecha');
fecha.masks.custom = 'HH:mm:ss';
const customFormattedDate = fecha.format(new Date(), 'custom');
console.log(customFormattedDate); // Outputs: current time in 'HH:mm:ss' format

Other packages similar to fecha

moment

Moment.js is a comprehensive library for parsing, validating, manipulating, and formatting dates. It offers a wide range of features and is widely used, but it is larger in size compared to 'fecha'.

date-fns

date-fns provides a set of functions for manipulating JavaScript dates in a functional programming style. It is modular and tree-shakeable, making it a lightweight alternative to Moment.js.

dayjs

Day.js is a minimalist JavaScript library that parses, validates, manipulates, and displays dates and times. It is similar to Moment.js but much smaller in size, making it a good alternative for performance-sensitive applications.

README

fecha

Lightweight date formatting and parsing (~2KB). Meant to replace parsing and formatting functionality of moment.js.

NPM

npm install fecha --save

Yarn

yarn add fecha

Fecha vs Moment

	Fecha	Moment
Size (Min. and Gzipped)	2.1KBs	13.1KBs
Date Parsing	✓	✓
Date Formatting	✓	✓
Date Manipulation		✓
I18n Support	✓	✓

Use it

Formatting

format accepts a Date object (or timestamp) and a string format and returns a formatted string. See below for available format tokens.

Note: format will throw an error when passed invalid parameters

import { format } from 'fecha';

type format = (date: Date, format?: string, i18n?: I18nSettings) => str;

// Custom formats
format(new Date(2015, 10, 20), 'dddd MMMM Do, YYYY'); // 'Friday November 20th, 2015'
format(new Date(1998, 5, 3, 15, 23, 10, 350), 'YYYY-MM-DD hh:mm:ss.SSS A'); // '1998-06-03 03:23:10.350 PM'

// Named masks
format(new Date(2015, 10, 20), 'isoDate'); // '2015-11-20'
format(new Date(2015, 10, 20), 'mediumDate'); // 'Nov 20, 2015'
format(new Date(2015, 10, 20, 3, 2, 1), 'isoDateTime'); // '2015-11-20T03:02:01-05:00'
format(new Date(2015, 2, 10, 5, 30, 20), 'shortTime'); // '05:30'

// Literals
format(new Date(2001, 2, 5, 6, 7, 2, 5), '[on] MM-DD-YYYY [at] HH:mm'); // 'on 03-05-2001 at 06:07'

Parsing

parse accepts a Date string and a string format and returns a Date object. See below for available format tokens.

NOTE: parse will throw an error when passed invalid string format or missing format. You MUST specify a format.

import { parse } from 'fecha';

type parse = (dateStr: string, format: string, i18n?: I18nSettingsOptional) => Date|null;

// Custom formats
parse('February 3rd, 2014', 'MMMM Do, YYYY'); // new Date(2014, 1, 3)
parse('10-12-10 14:11:12', 'YY-MM-DD HH:mm:ss'); // new Date(2010, 11, 10, 14, 11, 12)

// Named masks
parse('5/3/98', 'shortDate'); // new Date(1998, 4, 3)
parse('November 4, 2005', 'longDate'); // new Date(2005, 10, 4)
parse('2015-11-20T03:02:01-05:00', 'isoDateTime'); // new Date(2015, 10, 20, 3, 2, 1)

// Override i18n
parse('4 de octubre de 1983', 'M de MMMM de YYYY', {
  monthNames: [
    'enero',
    'febrero',
    'marzo',
    'abril',
    'mayo',
    'junio',
    'julio',
    'agosto',
    'septiembre',
    'octubre',
    'noviembre',
    'diciembre'
  ]
}); // new Date(1983, 9, 4)

i18n Support

import {setGlobalDateI18n} from 'fecha';

/*
Default I18n Settings
{
  dayNamesShort: ['Sun', 'Mon', 'Tue', 'Wed', 'Thur', 'Fri', 'Sat'],
  dayNames: ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'],
  monthNamesShort: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'],
  monthNames: ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'],
  amPm: ['am', 'pm'],
  // D is the day of the month, function returns something like...  3rd or 11th
  DoFn(dayOfMonth) {
    return dayOfMonth + [ 'th', 'st', 'nd', 'rd' ][ dayOfMonth % 10 > 3 ? 0 : (dayOfMonth - dayOfMonth % 10 !== 10) * dayOfMonth % 10 ];
  }
}
*/

setGlobalDateI18n({
  dayNamesShort: ['Sun', 'Mon', 'Tue', 'Wed', 'Thur', 'Fri', 'Sat'],
  dayNames: ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'],
  monthNamesShort: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'],
  monthNames: ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'],
  amPm: ['am', 'pm'],
  // D is the day of the month, function returns something like...  3rd or 11th
  DoFn: function (D) {
    return D + [ 'th', 'st', 'nd', 'rd' ][ D % 10 > 3 ? 0 : (D - D % 10 !== 10) * D % 10 ];
  }
});

Custom Named Masks

import { format, setGlobalDateMasks } from 'fecha';
/*
Default global masks
{
  default: 'ddd MMM DD YYYY HH:mm:ss',
  shortDate: 'M/D/YY',
  mediumDate: 'MMM D, YYYY',
  longDate: 'MMMM D, YYYY',
  fullDate: 'dddd, MMMM D, YYYY',
  shortTime: 'HH:mm',
  mediumTime: 'HH:mm:ss',
  longTime: 'HH:mm:ss.SSS'
}
*/

// Create a new mask
setGlobalDateMasks({
  myMask: 'HH:mm:ss YY/MM/DD';
});

// Use it
format(new Date(2014, 5, 6, 14, 10, 45), 'myMask'); // '14:10:45 14/06/06'

Formatting Tokens

	Token	Output
Month	M	1 2 ... 11 12
	MM	01 02 ... 11 12
	MMM	Jan Feb ... Nov Dec
	MMMM	January February ... November December
Day of Month	D	1 2 ... 30 31
	Do	1st 2nd ... 30th 31st
	DD	01 02 ... 30 31
Day of Week	d	0 1 ... 5 6
	ddd	Sun Mon ... Fri Sat
	dddd	Sunday Monday ... Friday Saturday
Year	YY	70 71 ... 29 30
	YYYY	1970 1971 ... 2029 2030
AM/PM	A	AM PM
	a	am pm
Hour	H	0 1 ... 22 23
	HH	00 01 ... 22 23
	h	1 2 ... 11 12
	hh	01 02 ... 11 12
Minute	m	0 1 ... 58 59
	mm	00 01 ... 58 59
Second	s	0 1 ... 58 59
	ss	00 01 ... 58 59
Fractional Second	S	0 1 ... 8 9
	SS	0 1 ... 98 99
	SSS	0 1 ... 998 999
Timezone	Z	-07:00 -06:00 ... +06:00 +07:00
	ZZ	-0700 -0600 ... +0600 +0700

Changelog

4.2.3

• Fixed bug with UTC date on daylights savings time #94