ksef2 0.6.2

Python SDK and Tools for Poland's KSeF (Krajowy System e-Faktur) API

Python SDK and Tools for Poland's KSeF (Krajowy System e-Faktur) v2.0 API.

Installation

uv add ksef2

Requires Python 3.12+.

Quick Start

from datetime import datetime, timezone
from ksef2 import Client, Environment, FormSchema
from ksef2.core.xades import generate_test_certificate
from ksef2.domain.models import (
    InvoiceQueryFilters, InvoiceSubjectType, InvoiceQueryDateRange, DateType,
)

NIP = "5261040828"
client = Client(Environment.TEST)

# Authenticate (XAdES — TEST environment)
cert, key = generate_test_certificate(NIP)
tokens = client.auth.authenticate_xades(nip=NIP, cert=cert, private_key=key)

with client.sessions.open_online(
    access_token=tokens.access_token.token,
    form_code=FormSchema.FA3,
) as session:

    # Send an invoice
    result = session.send_invoice(open("invoice.xml", "rb").read())
    print(result.reference_number)

    # Check processing status
    status = session.get_invoice_status(result.reference_number)

    # Export invoices matching a query
    export = session.schedule_invoices_export(
        filters=InvoiceQueryFilters(
            subject_type=InvoiceSubjectType.SUBJECT1,
            date_range=InvoiceQueryDateRange(
                date_type=DateType.ISSUE,
                from_=datetime(2026, 1, 1, tzinfo=timezone.utc),
                to=datetime.now(tz=timezone.utc),
            ),
        ),
    )

    # Download the exported package
    export_result = session.get_export_status(export.reference_number)
    if package := export_result.package:
        for path in session.fetch_package(package=package, target_directory="downloads"):
            print(f"Downloaded: {path}")

Full runnable version: send_query_export_download.py — more examples in scripts/examples.

Token Authentication

For production, or when you have a pre-generated KSeF token:

from ksef2 import Client, Environment

# uses production environment by default
client = Client()

tokens = client.auth.authenticate_token(
    ksef_token="your-ksef-token",
    nip=VALID_NIP,
)
print(tokens.access_token.token)

Development

just sync          # Install all dependencies (including dev)
just test          # Run unit tests
just regenerate-models  # Regenerate OpenAPI models

Other commands

just integration   # Run integration tests (requires KSEF credentials in .env)
just coverage       # Calculate API coverage (updates coverage.json)
just fetch-spec     # Fetch latest OpenAPI spec from KSeF

API Coverage

The SDK currently covers 33 of 77 KSeF API endpoints (43%). Calculated via scripts/api_coverage.py. See individual feature docs for endpoint details:

• Authentication
• Invoices
• Sessions
• Tokens
• Test Data
• Limits

License

MIT