Email details: Appointment

[kulmann]

Initial Checklist

• I understand this is a user story and questions should be posted in the Community Discussions
• I searched issues and couldn’t find anything (or linked relevant results below)

User Story

• As an email app user, I want to see details about an attached appointment inlined into the email body so that I can see appointment details at a glance.

User Value

Reading emails

Acceptance Criteria

• If an email has a iCalendar file (.ics) attached, appoint details get rendered as a card above the email body (see attached mockups)
• .ics file gets parsed client side
• card is collapsed by default and shows the following information about the appointment:
  • title
  • date
  • time (from and until)
  • a button for expanding the card
• if the card is expanded it shows the following additional information about the appointment:
  • Organizer (headline and email addresses)
  • Participants (headline and full list of email addresses)
  • Add to Calendar button
• As long as we don't have a calendar integration, the button downloads the .ics file for adding it to a locally installed calendar application

Mockups

[db-ot]

• ICS file as downloadable "attachement" under

[AlexAndBear]

I think we should also limit the amount of ics files that we parse and show in the front end. If someone sends a malicious email with 100 ics files. The client would need to download all files and parse them, could end up in a freezing browser for the user.

I think parsing the first 3 ics/ical files per email should be a good limit.

For parsing, https://www.npmjs.com/package/ical.js seems to be a reliable lib.

cc @tammi-23 @kulmann