Ask HN: API for Printers?

I'm trying to automate receiving shipping containers at our warehouse. Part of it requires printing ~3 documents so the warehouse team can inspect and label the products coming in.

I'd like to automate this process, so our non-technical warehouse staff doesn't have to mess around in our archaic ERP system just to get to the print documents.

Is there an API for printers (specifically Brother or Canon)? Or another way to trigger print jobs?