Projektstart

backend/node_modules/cron-parser/README.md

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+cron-parser
+================
+
+[![Build Status](https://github.com/harrisiirak/cron-parser/actions/workflows/push.yml/badge.svg?branch=master)](https://github.com/harrisiirak/cron-parser/actions/workflows/push.yml)
+[![NPM version](https://badge.fury.io/js/cron-parser.png)](http://badge.fury.io/js/cron-parser)
+
+Node.js library for parsing and manipulating crontab instructions. It includes support for timezones and DST transitions.
+
+__Compatibility__  
+Node >= 12.0.0
+TypeScript >= 4.2
+
+Setup
+========
+```bash
+npm install cron-parser
+```
+
+Supported format
+========
+
+```
+*    *    *    *    *    *
+┬    ┬    ┬    ┬    ┬    ┬
+│    │    │    │    │    |
+│    │    │    │    │    └ day of week (0 - 7, 1L - 7L) (0 or 7 is Sun)
+│    │    │    │    └───── month (1 - 12)
+│    │    │    └────────── day of month (1 - 31, L)
+│    │    └─────────────── hour (0 - 23)
+│    └──────────────────── minute (0 - 59)
+└───────────────────────── second (0 - 59, optional)
+```
+
+Supports mixed use of ranges and range increments (W character not supported currently). See tests for examples.
+
+Usage
+========
+
+Simple expression.
+
+```javascript
+var parser = require('cron-parser');
+
+try {
+  var interval = parser.parseExpression('*/2 * * * *');
+
+  console.log('Date: ', interval.next().toString()); // Sat Dec 29 2012 00:42:00 GMT+0200 (EET)
+  console.log('Date: ', interval.next().toString()); // Sat Dec 29 2012 00:44:00 GMT+0200 (EET)
+
+  console.log('Date: ', interval.prev().toString()); // Sat Dec 29 2012 00:42:00 GMT+0200 (EET)
+  console.log('Date: ', interval.prev().toString()); // Sat Dec 29 2012 00:40:00 GMT+0200 (EET)
+} catch (err) {
+  console.log('Error: ' + err.message);
+}
+
+```
+
+Iteration with limited timespan. Also returns ES6 compatible iterator (when iterator flag is set to true).
+
+```javascript
+var parser = require('cron-parser');
+
+var options = {
+  currentDate: new Date('Wed, 26 Dec 2012 12:38:53 UTC'),
+  endDate: new Date('Wed, 26 Dec 2012 14:40:00 UTC'),
+  iterator: true
+};
+
+try {
+  var interval = parser.parseExpression('*/22 * * * *', options);
+
+  while (true) {
+    try {
+      var obj = interval.next();
+      console.log('value:', obj.value.toString(), 'done:', obj.done);
+    } catch (e) {
+      break;
+    }
+  }
+
+  // value: Wed Dec 26 2012 14:44:00 GMT+0200 (EET) done: false
+  // value: Wed Dec 26 2012 15:00:00 GMT+0200 (EET) done: false
+  // value: Wed Dec 26 2012 15:22:00 GMT+0200 (EET) done: false
+  // value: Wed Dec 26 2012 15:44:00 GMT+0200 (EET) done: false
+  // value: Wed Dec 26 2012 16:00:00 GMT+0200 (EET) done: false
+  // value: Wed Dec 26 2012 16:22:00 GMT+0200 (EET) done: true
+} catch (err) {
+  console.log('Error: ' + err.message);
+}
+
+```
+
+Timezone support
+
+```javascript
+var parser = require('cron-parser');
+
+var options = {
+  currentDate: '2016-03-27 00:00:01',
+  tz: 'Europe/Athens'
+};
+
+try {
+  var interval = parser.parseExpression('0 * * * *', options);
+
+  console.log('Date: ', interval.next().toString()); // Date:  Sun Mar 27 2016 01:00:00 GMT+0200
+  console.log('Date: ', interval.next().toString()); // Date:  Sun Mar 27 2016 02:00:00 GMT+0200
+  console.log('Date: ', interval.next().toString()); // Date:  Sun Mar 27 2016 04:00:00 GMT+0300 (Notice DST transition)
+} catch (err) {
+  console.log('Error: ' + err.message);
+}
+```
+
+Manipulation 
+
+```javascript
+var parser = require('cron-parser');
+
+var interval = parser.parseExpression('0 7 * * 0-4');
+var fields = JSON.parse(JSON.stringify(interval.fields)); // Fields is immutable
+fields.hour = [8];
+fields.minute = [29];
+fields.dayOfWeek = [1,3,4,5,6,7];
+var modifiedInterval = parser.fieldsToExpression(fields);
+var cronString = modifiedInterval.stringify();
+console.log(cronString); // "29 8 * * 1,3-7"
+```
+
+Options
+========
+
+* *currentDate* - Start date of the iteration
+* *endDate* - End date of the iteration
+
+`currentDate` and `endDate` accept `string`, `integer` and `Date` as input.
+
+In case of using `string` as input, not every string format accepted
+by the `Date` constructor will work correctly. 
+The supported formats are: 
+- [`ISO8601`](https://moment.github.io/luxon/#/parsing?id=iso-8601)
+- [`HTTP and RFC2822`](https://moment.github.io/luxon/#/parsing?id=http-and-rfc2822)
+- [`SQL`](https://moment.github.io/luxon/#/parsing?id=sql) 
+
+The reason being that those are the formats accepted by the
+[`luxon`](https://moment.github.io/luxon/) library which is being used to handle dates.
+
+Using `Date` as an input can be problematic specially when using the `tz` option. The issue being that, when creating a new `Date` object without
+any timezone information, it will be created in the timezone of the system that is running the code. This (most of times) won't be what the user
+will be expecting. Using one of the supported `string` formats will solve the issue(see timezone example).
+
+* *iterator* - Return ES6 compatible iterator object 
+* *utc* - Enable UTC
+* *tz* - Timezone string. It won't be used in case `utc` is enabled
+
+Last weekday of the month
+=========================
+
+This library supports parsing the range `0L - 7L` in the `weekday` position of
+the cron expression, where the `L` means "last occurrence of this weekday for
+the month in progress".
+
+For example, the following expression will run on the last monday of the month
+at midnight:
+
+```
+0 0 0 * * 1L
+```
+
+The library also supports combining `L` expressions with other weekday
+expressions. For example, the following cron will run every Monday as well
+as the last Wednesday of the month:
+
+```
+0 0 0 * * 1,3L
+```