fix(participant exports): fix participants by returning the export type as well as the file path

We previously used the Apollo context but that's really unreliable.

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

lib/graphql/resolvers/participant.ex

@@ -302,7 +302,7 @@ defmodule Mobilizon.GraphQL.Resolvers.Participant do
         if can_event_be_updated_by?(event, moderator_actor) do
           case export_format(format, event, roles, locale) do
             {:ok, path} ->
-              {:ok, path}
+              {:ok, %{path: path, format: format}}
 
             {:error, :export_dependency_not_installed} ->
               {:error,

lib/graphql/schema/events/participant.ex

@@ -61,6 +61,12 @@ defmodule Mobilizon.GraphQL.Schema.Events.ParticipantType do
     field(:total, :integer, description: "The total number of participants in the list")
   end
 
+  object :participant_export do
+    meta(:authorize, :user)
+    field(:path, :string, description: "The path to the exported file")
+    field(:format, :export_format_enum, description: "The path to the exported file")
+  end
+
   @desc """
   The possible values for a participant role
   """
@@ -132,7 +138,7 @@ defmodule Mobilizon.GraphQL.Schema.Events.ParticipantType do
     end
 
     @desc "Export the event participants as a file"
-    field :export_event_participants, :string do
+    field :export_event_participants, :participant_export do
       arg(:event_id, non_null(:id),
         description: "The ID from the event for which to export participants"
       )