API endpoint: /api.php
GET /api.php?fn=ping GET /api.php?fn=list&dir=/ POST /api.php?fn=mkdir (dir=/, name=Folder) POST /api.php?fn=delete (path=/Folder/file.txt) POST /api.php?fn=upload (dir=/) [multipart: file=@...] GET /api.php?fn=getfile&path=/Folder/file.txt