e-Invoice Core Engine
The shared foundation for country e-invoicing connectors
A jurisdiction-agnostic toolkit that powers UBL 2.1 and canonical JSON generation, cryptographic sealing, QR codes, validation and secure transport. Install it once; your country connector modules plug straight in. Compatible with Odoo 18 and Odoo 19.
What is inside
UBL 2.1 Builder
Invoice and credit note documents with supplier/customer party blocks, invoice lines with allowances and charges, tax subtotal aggregation, monetary totals, payment means and terms, and base64 attachment embedding.
Canonical JSON Builder
Ordered-key serialization with configurable per-field decimal precision and a whitespace-free canonical string ready for signing in JSON-regime jurisdictions.
Signing (BYOK)
Enveloped XML-DSig with SHA-256 digests and exclusive C14N, plus a detached JWS variant for JSON regimes. Your certificate and key stay in your database and never leave it.
QR Engine
TLV+base64, plain-URL and JSON QR payloads with PNG rendering for invoice reports.
Validation Framework
A declarative rule engine with a generic EN 16931-style core rule set: required seller and buyer data, line math, tax total coherence, currency checks and date formats. Returns a structured error report.
BYOK REST Transport
A resilient request layer with exponential retry/backoff, bearer, api-key, basic and client-certificate authentication, sandbox and production switching, timeouts and full request/response logging.
Built to extend
Country connectors register a profile and a generator hook against this engine. The core carries no country-specific logic, so a single tested foundation serves every jurisdiction.
Data disclosure
This module sends data only to the endpoints you configure in your country connector. No invoice data is transmitted anywhere else, and your certificate and private key never leave your database.
Screenshots
Documents
Profiles
Document
Documents List
Profiles
Update date: 2026-07-22