Something like a InvoiceGatewayProvider or EERP / CRM Connections.

[SamBrishes]

Since Mall supports the connection of external payment service providers in the purchase process via the PaymentProviderGateway class, we should (perhaps) also allow external invoicing providers via a separate InvoiceProviderGateway.

Some known providers are...

• easybill.de
• invoiceninja.com
• JTL-software.de

Of course, most such providers also support product and customer management, so we still need to clarify how far the interface should go and whether we should enable a pure invoice handling or a full EERP / CRM interface.

Either way, most of the code should be in the respective interfaces, of course.

Maybe most of it can already be solved via hooks?

What do you think?