stevo01 / python-en16931

A Python 3 package to parse, generate and manage the EN16931 Invoice format.

python-en16931

Python 3 package to read, write and manage the new EN16931 Invoice format.

This European Standard establishes a semantic data model of the core elements of an electronic invoice. The semantic model includes only the essential information elements that an electronic invoice needs to ensure legal (including fiscal) compliance and to enable interoperability for cross-border, cross sector and for domestic trade.

Features

This library allows you to:

1. De-serialize an XML in EN16931 format to a python Invoice object.
2. Serialize a python Invoice object to a valid XML representation.
3. Validate an Invoice using validex.
4. Import an Invoice to B2BRouter.

Installation

You can use pip to install this package:

$ pip install en16931

Usage

You can import an invoice from an XML file:

>>> from en16931 import Invoice
>>> invoice = Invoice.from_xml('en16931/tests/files/invoice.xml')

And use the API to access its internal values and entities:

>>> invoice.issue_date
datetime.datetime(2018, 6, 11, 0, 0)
>>> invoice.seller_party
<en16931.entity.Entity at 0x7f2b7c12b860>
>>> invoice.buyer_party
<en16931.entity.Entity at 0x7f2b7c0fd160>
>>> invoice.unique_taxes
{ Tax S: 0.21  , Tax S: 0.1  }
>>> invoice.lines
[<en16931.invoice_line.InvoiceLine at 0x7f2b7c0fd400>,
 <en16931.invoice_line.InvoiceLine at 0x7f2b7c0fd518>,
 <en16931.invoice_line.InvoiceLine at 0x7f2b7c0fd748>]
>>> invoice.tax_exclusive_amount
87.00
>>> invoice.tax_amount()
16.62
>>> invoice.tax_inclusive_amount
103.62
>>> invoice.payable_amount
103.62

If you import an XML file, all relevant quantities are not computed; we use the ones defined on the XML. You can check that the computed and imported quantities match by calling the relevant methods:

>>> assert invoice.tax_exclusive_amount == invoice.subtotal()
True
>>> assert invoice.tax_inclusive_amount == invoice.total()
True
>>> assert invoice.payable_amount == invoice.total()
True

Or you can also build, step by step, an invoice:

>>> from en16931 import Invoice
>>> invoice = Invoice(invoice_id="2018-01", currency="EUR")
>>> seller = Entity(name="Acme Inc.", tax_scheme="VAT",
...                 tax_scheme_id="ES34626691F", country="ES",
...                 party_legal_entity_id="ES34626691F",
...                 registration_name="Acme INc.", mail="[email protected]",
...                 endpoint="ES76281415Y", endpoint_scheme="ES:VAT",
...                 address="easy street", postalzone="08080",
...                 city="Barcelona")
>>> buyer = Entity(name="Corp Inc.", tax_scheme="VAT",
...                tax_scheme_id="ES76281415Y", country="ES",
...                party_legal_entity_id="ES76281415Y",
...                registration_name="Corp INc.", mail="[email protected]",
...                endpoint="ES76281415Y", endpoint_scheme="ES:VAT",
...                address="busy street", postalzone="08080",
...                city="Barcelona")
>>> invoice.buyer_party = buyer
>>> invoice.seller_party = seller
>>> invoice.due_date = "2018-09-11"
>>> invoice.issue_date = "2018-06-11"
>>> # lines
>>> il1 = InvoiceLine(quantity=11, unit_code="EA", price=2,
...                   item_name='test 1', currency="EUR",
...                   tax_percent=0.21, tax_category="S")
>>> il2 = InvoiceLine(quantity=2, unit_code="EA", price=25,
...                   item_name='test 2', currency="EUR",
...                   tax_percent=0.21, tax_category="S")
>>> il3 = InvoiceLine(quantity=5, unit_code="EA", price=3,
...                   item_name='test 3', currency="EUR",
...                   tax_percent=0.1, tax_category="S")
>>> invoice.add_lines_from([il1, il2, il3])

And serialize it to XML:

>>> # As a string
>>> xml = invoice.to_xml()
>>> # Or save it directly to a file
>>> invoice.save('example_invoice.xml')

Limitations

This is a proof of concept implementation and not all features defined in the EN16931 standard are implemented. But it is easy, in some cases trivial, to implement them. The main not implemented features are:

• CreditNotes are not supported.
• File attachments are not supported.
• Delivery information is not supported.
• Only global charges and discounts are supported. Line discounts and charges are not supported.
• Other potentially useful attributes (such as InvoicePeriod, BuyerReference, OrderReference, BillingReference, ContractDocumentReference, among others) are not implemented.

If you need a particular feature implemented, see the following section for feature requests.

Bugs and Feature Requests

Please report any bugs that you find here. Or, even better, fork the repository on GitHub and create a pull request (PR). We welcome all changes, big or small.

License

Released under the Apache License Version 2.0 (see LICENSE.txt):

Copyright (C) 2018 Invinet Sistemes