RunKit + npm: ical-generator

const ical = require('ical-generator'); const cal = ical({domain: 'localhost'}); const data = { "address": "", "attendeesCount": 0, "authorId": "Rikke", "canComment": true, "commentsCount": 0, "content": "Test", "endDateTime": 1593727200, "eventType": "Activity", "geonameId": "2622170", "id": "PRL3iujYMiE57LglNwgj", "media": [ "https://firebasestorage.googleapis.com/v0/b/minlan…=media&token=ff111bb0-fa75-4412-9cb1-c16e1aab6449", "https://firebasestorage.googleapis.com/v0/b/minlan…=media&token=e2cb61d6-5485-4267-b895-212bcc26e1a2", "https://firebasestorage.googleapis.com/v0/b/minlan…=media&token=a6c32ec2-3041-4674-874e-545b30ad730b" ], "postalCode": "", "startDateTime": 1593684000, "tags": [], "title": "Test", "unionId": null, "viewsCount": 0, "villgInfo": { "geonameId": "2622170", "toponymName": "Fjaltring" } } var media = data['media'][0]; cal.domain('example.com'); const event = cal.createEvent({ start: new Date(), end: new Date(), summary: 'Example Event', description: 'It works ;)', organizer: 'Organizer\'s Name <organizer@example.com>', url: 'https://example.com', x: { "X-IMAGE;FMTTYPE": `${media}` } }); // update event's description event.description('It still works ;)'); cal.toString();