Calendar entries are displayed in inviter's timezone

[kjendal]

I'm using icals published from Office365. Events are shown in the originators timezone (not local timezone).
Using latest release. Cloned 6/28/2020.

[kjendal]

After some additional testing, it looks like the timezone is ignored and the time is used and local timezone is assumed.

My timezone is US EST. Calendar entries with
DTSTART;TZID=Eastern Standard Time:20200610T070000
DTEND;TZID=Eastern Standard Time:20200610T083000
are displayed correctly.

Here is a snippet of the ICS that is related to the problem:

BEGIN:VEVENT
UID:D08BB6CB0CBB4600A25486726835A759HLLORA
SUMMARY:[EXTERNAL]TC Monthly Telechat meeting
DTSTART;TZID=America/Los_Angeles:20200603T070000
DTEND;TZID=America/Los_Angeles:20200603T080000
CLASS:PUBLIC
PRIORITY:5
DTSTAMP:20200629T131911Z
TRANSP:OPAQUE
STATUS:CONFIRMED
SEQUENCE:0

...

[kjendal]

I have this working now, but its a bit of a hack. For those interested:
ical.js does not handle timezones at all to address this, start with the patch from https://github.com/yyolk/node-ical-improved but support timeformats without 'Z' notation (UTC)

//typical RFC date-time format
      var comps = /^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(Z)?$/.exec(val);
      if (comps !== null) {
        if (comps[7] == 'Z'){ // GMT
          //newDate = new Date(Date.UTC(
            //parseInt(comps[1], 10),
            //parseInt(comps[2], 10)-1,
            //parseInt(comps[3], 10),
            //parseInt(comps[4], 10),
            //parseInt(comps[5], 10),
            //parseInt(comps[6], 10 )
          //));
          // TODO add tz
        } else {
          //newDate = new Date(
            //parseInt(comps[1], 10),
            //parseInt(comps[2], 10)-1,
            //parseInt(comps[3], 10),
            //parseInt(comps[4], 10),
            //parseInt(comps[5], 10),
            //parseInt(comps[6], 10)
          //);            
        }
        newDate = require('moment-timezone').tz(val.toString(), (parseParams(params).TZID || '')).tz('America/New_York').toDate();
        newDate = addTZ(newDate, params);
    }

Also, Outlook (at least) uses its own (apparently) TZID notation. The few that I tried need to be added to the timezone data from moment-timezone:

 // link some timezones for MS Outlook iCal
      var moment = require('moment-timezone');
        moment.tz.link([
        'America/New_York|Eastern Standard Time',
        'America/New_York|Eastern Daylight Time',
        'America/Chicago|Central Standard Time',
        'America/Chicago|Central Daylight Time',
        'America/Denver|Mountain Standard Time',
        'America/Denver|Mountain Daylight Time',
        'America/Los_Angeles|Pacific Standard Time',
        'America/Los_Angeles|Pacific Daylight Time',
        'Europe/Brussels|W. Europe Standard Time'
        ]);

I'm sure there is a better way to do this, but at least it is working...

I have a complete list outlook/MS timezone names to moment-timezone mappings if anyone is interested.