date-genie

date-genie is a Javascript date manipulation library written in Typescript. Use it to count the number of weeks or months that have occured since the Unix epoch.

Disclaimer

This library has been thoroughly tested in UTC (Zulu Time) environments. Running this code in a timezone other than UTC could produce unpredictable results.

Installation

Use the package manager npm to install date-genie.

npm install date-genie

Usage

import genie from 'date-genie';

getWeek(Date, TimezoneOffset)

Provided a given Date, return the number of full weeks that have occured before this date + 1. Monday is considered the first day of the week.

TimezoneOffset is optional. If supplied, it shifts the date to the specified timezone using the offset. Otherwise it defaults to 0.

// Tuesday, November 5th, 2019
var date = new Date("2019-11-05T00:00:00.000Z"); 
var result = genie.getWeek(date);
// result = 2601 because November 5th, 2019 is in the 2601st week since the Unix epoch

// Using TimezoneOffset
// Sunday, November 3rd, 2019 @ 10pm PST
// Note that the UTC date is November 4th but the TimezoneOffset shifts it back
var date = new Date("2019-11-04T06:00:00.000Z");
var timezoneOffset = 480;
var result = genie.getWeek(date, timezoneOffset);
// result = 2600 because November 3rd, 2019 is in the 2600th week since the Unix epoch

getMonth(Date, TimezoneOffset)

Provided a given Date, return the number of full months that have occured before this date + 1.

TimezoneOffset is optional. If supplied, it shifts the date to the specified timezone using the offset. Otherwise it defaults to 0.

// Friday, November 1st, 2019
var date = new Date("2019-11-01T00:00:00.000Z"); 
var result = genie.getMonth(date);
// result = 599 because November 2019 is the 599th month since the Unix epoch

Roadmap

• Add support for dates before 1970. Currently only dates after January 1st, 1970 are supported and have been tested.
• Allow the day a week starts to be adjusted for getWeek. Currently defaults to Monday.
• Support environments operating in timezones other than UTC.
• Solve Year 2038 problem

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to add/update tests as appropriate.

# Build and run tests
npm test

# Compile TypeScript into ./build
tsc

# Build for distribution
gulp

License

ISC