export const checkValidChars = ( value: string ) => { const validChars = /^([\u0E00-\u0E7Fa-z0-9-._*]+)$/g; return validChars.test( value ); }; export default function validateDomain( value: string ) { try { if ( value ) { // Only allow domains with a dot in them (not localhost, for example). if ( ! value.includes( '.' ) ) { throw new Error( 'Invalid domain' ); } let normalised = value; // If the domain doesn't start with http:// or https://, add https:// if ( ! normalised.startsWith( 'http://' ) && ! normalised.startsWith( 'https://' ) ) { normalised = 'https://' + normalised; } // Test if we can parse the URL. If we can't, it's invalid. const url = new URL( normalised ); // Check if the protocol is 'http' or 'https'. const protocolCheck = url.protocol === 'http:' || url.protocol === 'https:'; if ( ! protocolCheck ) { return false; } const { hostname } = url; return checkValidChars( hostname ); } return undefined; } catch ( e ) { return false; } }