KeepAttendees (Outlook -> Google Calendar) not setting any DisplayName (`(No name)` ) in sink

[frittentheke]

When using KeepAttendees (https://github.com/inovex/CalendarSync/blob/e449ad66e123d26ea2b590b9fcd0cebc3afe23b6/internal/transformation/keepAttendees.go#L22-L44) the email address is converted into some hash@localhost, but the displayname should then contain either the name or (email)address of the attendee.

Unfortunately for my setup using Outlook as source and Google Calendar as sink this does not seem to work. All appointments end up having attendees like this:

10489844856491519570@localhost
12212514355089931070@localhost
15921973589580864227@localhost
16338311574219248405@localhost
17242699230287863173@localhost
17352963055167261338@localhost
6873758520474437452@localhost
7320409542426832160@localhost
9405119741488794564@localhost

but with no DisplayName set (Google shows them with (No name). I also tried with the UseEmailAsDisplayName option enabled.

Looking at the source (https://developer.microsoft.com/en-us/graph/graph-explorer?request=me%2Fevents%3F%24select%3Dsubject%2Cbody%2CbodyPreview%2Corganizer%2Cattendees%2Cstart%2Cend%2Clocation&method=GET&version=v1.0&GraphUrl=https://graph.microsoft.com) I can see that the attendees all have am emailAddress containing two fields name and address:

[...]
 "body": {
            "attendees": [
                {
                    "type": "required",
                    "status": {
                        "response": "accepted",
                        "time": "0001-01-01T00:00:00Z"
                    },
                    "emailAddress": {
                        "name": "Rohmann, Christian [It is me - yeah]",
                        "address": "[email protected]"
                    }
                },
[...]

aligning with the model https://github.com/inovex/CalendarSync/blob/e449ad66e123d26ea2b590b9fcd0cebc3afe23b6/internal/adapter/outlook_http/models.go#L56-L63