Django Admin export selection as vCard action

vcard_export_action.py

from django.http import HttpResponse
from datetime import datetime

def export_as_vcard(modeladmin, request, queryset):
  """
  Export vCard admin action
  Update source to match your model
  
  Example usage:

  from vcard_export_action import export_as_vcard

  class YourModelAdmin(admin.ModelAdmin):
    list_display = (...)
    list_filter = [...]
    actions = [export_as_vcard("vCard Export", fields=[...])]
  """
  # Prepare vCard
  d = datetime.now()
  output = ""
  for person in queryset.all():
    person_output = """BEGIN:VCARD
VERSION:3.0
N:{last_name};{first_name}
FN:{first_name} {last_name}
TEL;TYPE=HOME,VOICE:{phone}
TEL;TYPE=WORK,VOICE:{secondary_phone}
EMAIL:{email}
REV:{rev}
END:VCARD"""
    person_output = person_output.format(
                        first_name = person.first_name, 
                        last_name = person.last_name,
                        phone = person.phone,
                        secondary_phone = person.secondary_phone,
                        email = person.email,
                        rev = d.strftime('%Y%M%d%H%f'),
                        )
    output += person_output
  # Prepare response
  response = HttpResponse(output, mimetype='text/vcard')
  if queryset.count() == 1:
    # Name the file after the person being exported
    filename = queryset[0].last_name + '_' + queryset[0].first_name
  else:
    # Or, if there are more than 1 person, name it after the datetime of the export
    filename = d.strftime('%Y%M%d%H%f') + '.vcf'  
  response['Content-Disposition'] = 'attachment; filename=%s' % filename
  return response

export_as_vcard.short_description = "Export as vCard"