ScanSnap WebDAV Service for buildersclub.ca

The Technical Journey

Simple Network Scanner Access

The system provides a straightforward network location where the ScanSnap scanner can send documents directly. Just connect with Command+K in Finder, enter the URL, and you have instant access to a network drive ready for scanning.

This creates a seamless experience - load your documents, hit scan, and they're immediately available on your computer without any additional steps or software.

Security Without the Headache

Here's the thing about receipt scanners: you want them to be fast and frictionless. Authentication dialogs kill that flow. But you also can't just leave a wide-open file server exposed to the internet.

The solution? Custom permissions at the protocol level. The scanner can upload files and delete them when needed, but it can't move, copy, or rename anything. More importantly, the service is completely isolated to its own directory—there's literally no way for it to access files outside ~/scansnap-dav/scans, even if someone tried to hack around it.

class ScanSnapProvider(FilesystemProvider):
    def create_collection(self, path):
        # No creating subdirectories
        raise DAVError(403, "Creating directories not allowed")
    
    def copy_resource(self, src_path, dest_path, depth):
        # No copying files around
        raise DAVError(403, "Copying not allowed")
    
    def move_resource(self, src_path, dest_path):
        # No moving or renaming
        raise DAVError(403, "Moving/renaming not allowed")

For the clubhouse environment, this works perfectly. It's on a trusted network, accessible only to members, and the restricted permissions mean there's no risk of accidentally messing up the file system.

The Storage Problem Nobody Thinks About

When you're scanning 50 receipts at a time, storage fills up fast. Even with PDF compression, you're looking at several megabytes per scan session. Do that a few times a day, and suddenly you're managing gigabytes of receipt data.

The fix? Automatic cleanup. Every night at 3 AM, a Python scheduler wipes the scans directory clean. Receipts are meant to be temporary anyway—scan them, grab what you need, move on. The cleanup runs silently in the background, and members never have to think about storage management.

def cleanup_scans():
    scans_dir = os.path.expanduser("~/scansnap-dav/scans")
    for filename in os.listdir(scans_dir):
        file_path = os.path.join(scans_dir, filename)
        if os.isfile(file_path):
            os.remove(file_path)

# Daily cleanup at 3:00 AM
schedule.every().day.at("03:00").do(cleanup_scans)