json.payload do
  json.array! @messages do |message|
    json.id message.id
    json.content message.content
    json.message_type message.message_type_before_type_cast
    json.content_type message.content_type
    json.content_attributes message.content_attributes
    json.created_at message.created_at.to_i
    json.conversation_id message.conversation.display_id
    json.attachments message.attachments.map(&:push_event_data) if message.attachments.present?
    json.sender message.sender.push_event_data if message.sender
  end
end
json.meta do
  json.contact_last_seen_at @conversation.contact_last_seen_at.to_i if @conversation.present?
end