post
https://api.apicbase.com/api/v2/procurement/purchase_orders//invoices/
Attaches an invoice file to a purchase order.
Note: This endpoint will be deprecated soon in favor of using Upload Invoices (with AI) or Upload Invoice File (no AI).
This endpoint attaches an invoice file directly to a purchase order without creating an invoice record in the system or performing any data extraction.
A purchase order can have up to 10 invoice files attached. One file can be uploaded per request. PDF and image formats are supported. The file size limit is 20 MB. Invoice files can be attached to purchase orders after they have transitioned to the SENT state. It is also possible to attach invoice files to delivered or partially delivered orders.