@facturion/invoice

The Facturion simplified-JSON invoice data model — a small, friendly JSON shape that covers the full EN 16931 semantic model, with validation and the canonical money math.

It ships:

• The JSON Schema (data/invoice-schema.json) — the canonical, language-neutral contract. Also exported as a runtime object.
• Validators — strict (every field required) and partial (nothing required; types, patterns and enums still enforced), built on Ajv with date-format checking.
• Derived TypeScript types — generated from the schema.
• Money math — lineNet and computeTotals (the net/VAT/totals chain down to the payable amount). Pure arithmetic, no presentation.

It owns no rendering or i18n. The HTML renderer (@facturion/invoice-renderer) and friendly code-list labels (@facturion/codelists) build on top.

Install

npm install @facturion/invoice

Usage

import {
  assertValidInvoice,
  validatePartialInvoice,
  computeTotals,
  invoiceSchema,
  type Invoice,
} from "@facturion/invoice";

const invoice: Invoice = JSON.parse(input);

// Strict gate for data you're about to process (throws InvoiceValidationError):
assertValidInvoice(invoice);

// Relaxed check for a draft/preview (types enforced, nothing mandatory):
if (!validatePartialInvoice(draft)) {
  // validatePartialInvoice.errors holds the Ajv error list
}

// Totals: line extension → tax basis → VAT → grand total → payable.
const { taxAmount, payable, taxSubtotals } = computeTotals(invoice);

The raw schema is available for tooling at @facturion/invoice/invoice-schema.json.

License

MIT. See LICENSE and NOTICE.