A timeline builder that stores an array of the date ranges that have been buffered by your application, as to reduce the amount of data your backend should load.

const timeline = new Timeline();
timeline.add(new Date(2023, 0, 1), new Date(2023, 0, 3));
timeline.add(new Date(2023, 0, 2), new Date(2023, 0, 6));

console.log(timeline);

// Output:
// [
//  DateRange {
//    start: 2023-01-01
//    end: 2023-01-06
//  }
// ]

Check out this code sample to see it in action.

Install

Add the timeline-builder package with npm:

npm install timeline-builder

or with yarn

yarn add timeline-builder

This library is written in TypeScript and has no dependencies.

Usage

Building the timeline

Instantiate the builder, that will keep the collection in memory:

const timeline = new Timeline();

There are two ways to fill up the timeline.

• Using plain date objects:

  timeline.add(new Date(2023, 0, 1), new Date(2023, 0, 3));
  timeline.add(new Date(2023, 0, 2), new Date(2023, 0, 6));

• Using a DateRange object, which is essentially a composition of a start date and end date object:

  timeline.addRange(new DateRange(new Date(2023, 0, 2), new Date(2023, 0, 6)));

  The DateRange class is used internally to compare overlapping ranges and merge them into one reconciled range.

Timeline actions

The following methods can be executed on the timeline:

• contains(start,end): checks if the range overlaps with the timeline
• containsAll(start, end): checks if the range is entirely within the timeline
• toList: creates a reconciled flat list of the timeline
• clear: clears the timeline
• count: a distinct count of the unique date ranges in the timeline

Tests

Unit tests are located in the test directory. Jest is used as the library. Run the tests by running yarn test.

License

MIT