wanasit/chrono

$ npm install --save chrono-node

import * as chrono from 'chrono-node';

chrono.parseDate('An appointment on Sep 12-13'); 

const chrono = require('chrono-node');

// or `import chrono from 'chrono-node'` for ECMAScript

import * as chrono from 'chrono-node';

chrono.parseDate('An appointment on Sep 12-13');
// Fri Sep 12 2014 12:00:00 GMT-0500 (CDT)
    
chrono.parse('An appointment on Sep 12-13');
/* [{ 
    index: 18,
    text: 'Sep 12-13',
    start: ...
}] */

parse(text: string, ref?: ParsingReference, option?: ParsingOption): ParsedResult[] {...}

// (Note: the examples run on JST timezone)

chrono.parseDate('Friday', new Date(2012, 8 - 1, 23)); 
// Fri Aug 24 2012 12:00:00 GMT+0900 (JST)

chrono.parseDate('Friday', new Date(2012, 8 - 1, 1)); 
// Fri Aug 03 2012 12:00:00 GMT+0900 (JST)

chrono.parseDate("Friday at 4pm", {
    // Wed Jun 09 2021 21:00:00 GMT+0900 (JST)
    // = Wed Jun 09 2021 07:00:00 GMT-0500 (CDT)
    instant: new Date(1623240000000), 
    timezone: "CDT",
})
// Sat Jun 12 2021 06:00:00 GMT+0900 (JST)
// = Fri Jun 11 2021 16:00:00 GMT-0500 (CDT)

const referenceDate = new Date(2012, 7, 25);
// Sat Aug 25 2012 00:00:00 GMT+0900 -- The reference date was Saturday

chrono.parseDate('Friday', referenceDate);
// Fri Aug 24 2012 12:00:00 GMT+0900 (JST) -- The day before was Friday

chrono.parseDate('Friday', referenceDate, { forwardDate: true });
// Fri Aug 31 2012 12:00:00 GMT+0900 (JST) -- The following Friday

// Chrono doesn't understand XYZ, so no timezone is parsed
chrono.parse('at 10:00 XYZ', new Date(2023, 3, 20))
// "knownValues": {"hour": 10, "minute": 0}

// Make Chrono parse XYZ as offset GMT-0300 (180 minutes)
chrono.parse('at 10:00 XYZ', new Date(2023, 3, 20), { timezones: { XYZ: -180 } })
// "knownValues": {"hour": 10, "minute": 0, "timezoneOffset": -180}

// Make Chrono parse XYZ as offset GMT-0300 outside of DST, and GMT-0200 during DST. Assume DST is between 
import { getLastDayOfMonthTransition } from "timezone";
import { Weekday, Month } from "parsing";

const parseXYZAsAmbiguousTz = {
  timezoneOffsetDuringDst: -120,
  timezoneOffsetNonDst: -180,
  dstStart: (year: number) => getLastWeekdayOfMonth(year, Month.FEBRUARY, Weekday.SUNDAY, 2),
  dstEnd: (year: number) => getLastWeekdayOfMonth(year, Month.SEPTEMBER, Weekday.SUNDAY, 3)
};
// Parsing a date which falls within DST
chrono.parse('Jan 1st 2023 at 10:00 XYZ', new Date(2023, 3, 20), { timezones: { XYZ: parseXYZAsAmbiguousTz } })
// "knownValues": {"month": 1, ..., "timezoneOffset": -180}

// Parsing a non-DST date
chrono.parse('Jun 1st 2023 at 10:00 XYZ', new Date(2023, 3, 20), { timezones: { XYZ: parseXYZAsAmbiguousTz } })
// "knownValues": {"month": 6, ..., "timezoneOffset": -120}

const results = chrono.parse('I have an appointment tomorrow from 10 to 11 AM');

results[0].index;     // 22
results[0].text;      // 'tomorrow from 10 to 11 AM'
results[0].refDate;   // Sat Dec 13 2014 21:50:14 GMT-0600 (CST)

// `start` is Sat Dec 14 2014 10:00:00
results[0].start.get('day');    // 14 (the 14th, the day after refDate)
results[0].start.get('month');  // 12 (or December)
results[0].start.get('hour');   // 10 
results[0].start.date();        // Sun Dec 14 2014 10:00:00 GMT-0600 (CST)

...
results[0].end.date();  // Sun Dec 14 2014 11:00:00 GMT-0600 (CST)

// 'strict' mode
chrono.strict.parseDate('Today');       // null
chrono.strict.parseDate('Friday');      // null
chrono.strict.parseDate('2016-07-01');  // Fri Jul 01 2016 12:00:00 ...
chrono.strict.parseDate('Jul 01 2016'); // Fri Jul 01 2016 12:00:00 ...

// 'casual' mode (default) 
chrono.parseDate('Today');              // Thu Jun 30 2016 12:00:00 ...
chrono.casual.parseDate('Friday');      // Fri Jul 01 2016 12:00:00 ...
chrono.casual.parseDate('2016-07-01');  // Fri Jul 01 2016 12:00:00 ...
chrono.casual.parseDate('Jul 01 2016'); // Fri Jul 01 2016 12:00:00 ...

// default English (US)
chrono.parseDate('6/10/2018');    

chrono.en.parseDate('6/10/2018');       // June 10th, 2018
chrono.en.GB.parseDate('6/10/2018');    // October 6th, 2018

chrono.ja.parseDate('昭和６４年１月７日'); 

Invalid regular expression: /* omitted */: Invalid property name in character class

// CommonJS (Node.js)
const chrono = require('chrono-node/en')

// ECMAScript
import chrono from 'chrono-node/en'

// TypeScript
// Warning: `moduleResolution` must be set to `node16` or `nodeNext` in tsconfig.json`
import * as chrono from 'chrono-node/en'

interface Parser {
    pattern: (context: ParsingContext) => RegExp,
    extract: (context: ParsingContext, match: RegExpMatchArray) =>
        (ParsingComponents | ParsingResult | {[c in Component]?: number} | null)
}

const custom = chrono.casual.clone();
custom.parsers.push({
    pattern: () => { return /\bChristmas\b/i },
    extract: (context, match) => {
        return {
            day: 25, month: 12
        }
    }
});

custom.parseDate("I'll arrive at 2.30AM on Christmas night");
// Wed Dec 25 2013 02:30:00 GMT+0900 (JST)
// 'at 2.30AM on Christmas'

interface Refiner {
    refine: (context: ParsingContext, results: ParsingResult[]) => ParsingResult[]
}

const custom = chrono.casual.clone();
custom.refiners.push({
    refine: (context, results) => {
        // If there is no AM/PM (meridiem) specified,
        //  let all time between 1:00 - 4:00 be PM (13.00 - 16.00)
        results.forEach((result) => {
            if (!result.start.isCertain('meridiem') &&
                result.start.get('hour') >= 1 && result.start.get('hour') < 4) {

                result.start.assign('meridiem', 1);
                result.start.assign('hour', result.start.get('hour') + 12);
            }
        });
        return results;
    }
});

// This will be parsed as PM.
// > Tue Dec 16 2014 14:30:00 GMT-0600 (CST) 
custom.parseDate("This is at 2.30");

// Unless the 'AM' part is specified
// > Tue Dec 16 2014 02:30:00 GMT-0600 (CST)
custom.parseDate("This is at 2.30 AM");

# Clone and install library
$ git clone https://github.com/wanasit/chrono.git chrono
$ cd chrono
$ npm install

# Run the test
$ npm run test

# Run the test in watch mode
$ npm run watch

$ npm run build