Peppol-py

A python implementation for sending peppol eDelivery AS4 documents. Most implementations are written in java such as oxalis and phase4 and are very complex. This code base is an order of magnitude smaller.

The implementation makes use of xmlsec for signing and encryption. Version 1.3 is needed for the rsa oaep aes128 gcm encryption used in peppol. Debian is still using 1.2 in both stable and unstable as of 5/6 2025 so we use xmlsec 1.3 as an external binary.

The protocol should be relatively simple:

• Generate a transfer document with:
  • UserMessage describing the sender and receiver
  • Empty body
  • The gzipped actual document as an attachment
• Hash the 3 elements and sign that.
• Encrypt the gzipped attachment for the intended receiver
• POST the transfer document with signature and encryption info, with the encrypted attachment as a multipart mime to the AS4 endpoint

The implementation includes support for using the SML and SMP protocol for finding the AS4 endpoint of the receiver.

CLI Usage

> python3 -m peppol_py --help

usage: python -m peppol_py [-h] [--verbose | --no-verbose] {send,validate} ...

Peppol utility

positional arguments:
  {send,validate}       command
    send                Send a Peppol document
    validate            Validate a Peppol document

options:
  -h, --help            show this help message and exit
  --verbose, --no-verbose
                        Enable debug logging

> python -m peppol_py send --help
usage: python -m peppol_py send [-h] --document DOCUMENT --service-provider SERVICE_PROVIDER
                                     [--xmlsec-path XMLSEC_PATH]
                                     [--schematron-path SCHEMATRON_PATH [SCHEMATRON_PATH ...]]
                                     [--keyfile KEYFILE] [--password PASSWORD] [--certfile CERTFILE]
                                     [--unwrap-sbh | --no-unwrap-sbh]
                                     [--test | --no-test]

options:
  -h, --help            show this help message and exit
  --document DOCUMENT   The path of the document to send
  --xmlsec-path XMLSEC_PATH
                        The path to latest xmlsec binary
  --schematron-path SCHEMATRON_PATH [SCHEMATRON_PATH ...]
                        Schematron XSL files to validate with, defaults to bundled PEPPOL-EN16931-UBL.xsl
  --keyfile KEYFILE     The path to the private key, defaults to key.pem
  --password PASSWORD   The password for the private key, defaults to empty
  --certfile CERTFILE   The path to the public key, defaults to cert.pem
  --unwrap-sbh, --no-unwrap-sbh
                        Unwrap standard business header already present in document. Useful for testbed.
  --service-provider SERVICE_PROVIDER
                        Service provider ID
  --test, --no-test     Use test SMP server, defaults to production

> python -m peppol_py validate --help
usage: python -m peppol_py validate [-h] --document DOCUMENT 
                                         [--schematron-path SCHEMATRON_PATH [SCHEMATRON_PATH ...]]

options:
  -h, --help            show this help message and exit
  --document DOCUMENT   The path of the document to validate
  --schematron-path SCHEMATRON_PATH [SCHEMATRON_PATH ...]
                        Schematron XSL files to validate with, defaults to bundled PEPPOL-EN16931-UBL.xsl

Examples

Send a document:

python3 -m peppol_py --verbose send --document test_invoice.xml \
        --schematron-path CEN-EN16931-UBL.xsl --test \
        --certfile cert.pem --keyfile key.pem \
        --service-provider PXX000000 

Validate a document:

python3 -m peppol_py validate --document test_invoice.xml \
        --schematron-path CEN-EN16931-UBL.xsl

Python API

Send document

To send a prepared xml document, call send_peppol_document:

from peppol_py import send_peppol_document
stats = send_peppol_document(
    document_content, xmlsec_path, keyfile, keyfile_password, certfile,
    sender_id=None, receiver_id=None, sender_country=None,
    document_type_version=None, test_environment=True, timeout=20, dryrun=False
)

See docstring or help(peppol_py.send_peppol_document) on a Python console for a full parameter description.

Validate document

To validate a prepared document, call validate_peppol_document:

from peppol_py import validate_peppol_document
stats = validate_peppol_document(
    document_content, schematron_xsls, remove_namespaces_from_errors=True, warnings=False
)

See docstring or help(peppol_py.validate_peppol_document) on a Python console for a full parameter description.

Send statistics

To validate a prepared document, call send_peppol_statistics:

from peppol_py import send_peppol_statistics

stats = send_peppol_statistics(
    aggr_stats, our_endpoint, xmlsec_path, keyfile, password, certfile,
    test_environment
)

See docstring or help(peppol_py.send_peppol_statistics) on a Python console for a full parameter description.

Background

This implementation was sponsored by iteras, one of the largest SSAS solutions in the nordics for managing print and digital media subscriptions.