download a dossier as zip with all attachments

app/lib/active_storage/downloadable_file.rb

@@ -0,0 +1,29 @@
+class ActiveStorage::DownloadableFile
+  def initialize(attached)
+    if using_local_backend?
+      @url = 'file://' + ActiveStorage::Blob.service.path_for(attached.key)
+    else
+      @url = attached.service_url
+    end
+  end
+
+  def url
+    @url
+  end
+
+  def self.create_list_from_dossier(dossier)
+    pjs = PiecesJustificativesService.liste_pieces_justificatives(dossier)
+    pjs.map do |pj|
+      [
+        ActiveStorage::DownloadableFile.new(pj.piece_justificative_file),
+        pj.piece_justificative_file.filename.to_s
+      ]
+    end
+  end
+
+  private
+
+  def using_local_backend?
+    [:local, :local_test, :test].include?(Rails.application.config.active_storage.service)
+  end
+end