When using the sale_supply (and specially sale_supply_drop_shipment) it’s important to know which quantity of products is available on the supplier side as this is information is usefull to decide if the customer order can be satified before confirming it.
Normally the unique way to know if the information is available is asking the supplier but nowadays is more common that suppliers expose this information to their customers (via webservice or a file updated periodically, etc.).
On the product supplier table add the following fields:
- Available Quantity: Float to represent the quantity that the supplier is ready to sell.
- Quantity Unit: The unit of measure to represent this quantity availble.
The requested quantity should be available on the find_best_supplier pattern, so if the supplier does not have enought available quantity to fill the request it should be skipped.