Hello @Callya !

Yes, UNA has the api for that. For example to add content to Posts module it's possible to call serviceEntityAdd service function:

curl -H 'Authorization: Bearer tmw.msZjv4MEpwBt6Gku6Wjzvu5i9DX7LkMZdC+8AbWar&px' "http://example.com/una/api.php?r=bx_posts/entity_add&params=%5B3%2C%7B%22title%22%3A%22Test%20title2%22%2C%22cat%22%3A3%2C%22text%22%3A%22Post%20text%22%2C%22allow_view_to%22%3A3%7D%5D"

So you may write the script, which, will parse your files with data and refer to this api page.