De-Caching Invoices

Although invoices are, effectively, just a collection of transactions (see Invoicing Concepts for some background) the underlying data can change.  For example, customer specific data (such as the customer’s address) could be modified.  Shipment details can also change over time.  However once you “post” an invoice the created PDF is static.  Even if you change the customer’s address, when you download a posted invoice it looks exactly as it did when you posted it.

This can be a useful element in transactional accounting as the document is unchanging.  However if a customer asks you to re-print their invoice with a different address you would be faced with having to cancel the invoice and produce a new one.

We have now introduced the concept of “de-caching” invoices.  When an invoice is de-cached it means we eliminate the PDF and the next time it is downloaded or viewed the PDF must be re-constructed with the latest data.