Attach event ics files to event-related emails

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/export/icalendar.ex

@@ -3,7 +3,7 @@ defmodule Mobilizon.Service.Export.ICalendar do
   Export an event to iCalendar format.
   """
 
-  alias Mobilizon.{Actors, Events, Users}
+  alias Mobilizon.{Actors, Config, Events, Users}
   alias Mobilizon.Actors.Actor
   alias Mobilizon.Addresses.Address
   alias Mobilizon.Events.{Event, FeedToken}
@@ -11,6 +11,8 @@ defmodule Mobilizon.Service.Export.ICalendar do
   alias Mobilizon.Storage.Page
   alias Mobilizon.Users.User
 
+  @vendor "Mobilizon #{Config.instance_version()}"
+
   @doc """
   Export a public event to iCalendar format.
 
@@ -19,12 +21,19 @@ defmodule Mobilizon.Service.Export.ICalendar do
   @spec export_public_event(Event.t()) :: {:ok, String.t()}
   def export_public_event(%Event{visibility: visibility} = event)
       when visibility in [:public, :unlisted] do
-    {:ok, %ICalendar{events: [do_export_event(event)]} |> ICalendar.to_ics(vendor: "Mobilizon")}
+    export_event(event)
   end
 
   @spec export_public_event(Event.t()) :: {:error, :event_not_public}
   def export_public_event(%Event{}), do: {:error, :event_not_public}
 
+  @doc """
+  Export an event to iCalendar format
+  """
+  def export_event(%Event{} = event) do
+    {:ok, %ICalendar{events: [do_export_event(event)]} |> ICalendar.to_ics(vendor: @vendor)}
+  end
+
   @spec do_export_event(Event.t()) :: ICalendar.Event.t()
   defp do_export_event(%Event{} = event) do
     %ICalendar.Event{