@automattic/social-previews/src/facebook-preview/helpers.ts

A suite of components to generate previews for a post for both social and search engines.

import { firstValid, hardTruncation, shortEnough, stripHtmlTags, Formatter } from '../helpers';

const TITLE_LENGTH = 110;
const DESCRIPTION_LENGTH = 200;
export const CUSTOM_TEXT_LENGTH = 440;

export const baseDomain: Formatter = ( url ) =>
	url
		.replace( /^[^/]+[/]*/, '' ) // strip leading protocol
		.replace( /\/.*$/, '' ); // strip everything after the domain

export const facebookTitle: Formatter = ( text ) =>
	firstValid(
		shortEnough( TITLE_LENGTH ),
		hardTruncation( TITLE_LENGTH )
	)( stripHtmlTags( text ) ) || '';

export const facebookDescription: Formatter = ( text ) =>
	firstValid(
		shortEnough( DESCRIPTION_LENGTH ),
		hardTruncation( DESCRIPTION_LENGTH )
	)( stripHtmlTags( text ) ) || '';