How to create automatic receipts for expense items ?

Summary:

How to create receipts automatically for expense items ?

Content (required):

There is a requirement to create automatic receipts for expense items ?

Without Supplier Portal:

Although the Suppliers can creates ASN with supplier portal, but Alternatively, a warehouse manager can enter an ASN by clicking the Create ASN task from the task panel of the Inventory Management work area.

The company does not want neither the Supplier nor the Warehouse Manager enter an ASN, they want to create the ASN and Receipt automatically for expense/services items.

I was thinking to extract daily the information from the inventory called "Expected Receipts for PO" in order to populate the receipts Web Service.