[Zope] store external documents to Zope

Hi first of all: I am a newbie to Zope, so please be patient with me. I want to save to Zope an external document automatically and for that I thought about a simple mechanism like this: The user got in his interface a send button to insert his document to the Zope portal. After pushing the send button his file will be added the the Zope source and readable in Zope. So how can I add a new document to the Zope portal without using the Zope interface ? Where do I have to add the document source to Zope ? Thank you a lot in advance ... J.