文件上传彻底的表格到电子邮件rails

hi i am trying to upload the PDF document from the form and directly to the controller and all i need is the full path of file is uploading.i was using remortipart but i cannot use it because its rails 5 project.and i am only getting path of my project directory is there any way i can get full path to file from any where in my computer.And i am trying to send file directly into email without saving it anywherehi i am trying to upload the PDF document from