I have been developing a Magento 2 plugin based upon the standard format being used here:
It all seems to be working well, but now we want to be able to take the information from the selected booking option and actually use it to book a shipment for the order.
On doing some research it seems the standard way to do this in Magento 2 is to go through Sales > Orders > View Order > Ship... At that point you can either add a tracking number for a manual shipment or (if it applies like for example the Magento 2 UPS module) select "Create Shipping Label" from the Shipment options and then follow this process through.
I have gone through the UPS module and it looks as though I have found the actual booking logic somewhere between the Carrier.php _doShipmentRequest and _sendShipmentAcceptRequest however I can't seem to find the logic that actually enables this checkbox. Can anyone advise where I should be looking for this?