OfficeIMO.Invoicing.Validation 3.5.2

OfficeIMO.Invoicing.Validation

Validate exact CII or UBL invoice bytes against an explicit schema and business-rule release. The package runs on .NET 8 and .NET 10. It makes no network requests.

Install

dotnet add package OfficeIMO.Invoicing.Validation --version 3.4.4

Build from source

From the repository root, pack both projects, then add the validation package to your application. NuGet resolves its invoice-model dependency from the same feed:

dotnet pack OfficeIMO.Invoicing/OfficeIMO.Invoicing.csproj -c Release -o artifacts/invoice-feed
dotnet pack OfficeIMO.Invoicing.Validation/OfficeIMO.Invoicing.Validation.csproj -c Release -o artifacts/invoice-feed
dotnet add path/to/Application.csproj package OfficeIMO.Invoicing.Validation --source artifacts/invoice-feed

PDF generation is independent of this package. Java and Saxon are required only when running the configured business-rule stage.

Validate Polish FA(3)

Fa3SchemaValidator validates exact FA(3) bytes against the official schema published on 25 June 2025, version 1-0E. Download these four files into one local directory, naming the main schema FA3.xsd:

var schemas = Fa3SchemaBundle.LoadDirectory("schemas/fa3");
var fa3Validator = new Fa3SchemaValidator(schemas);
var result = fa3Validator.Validate(File.ReadAllBytes("polish-invoice.xml"));
Console.WriteLine($"{result.Status}: {result.InputSha256}");
foreach (var diagnostic in result.Diagnostics)
    Console.WriteLine($"{diagnostic.Code}: {diagnostic.Message}");

The bundle verifies each SHA-256 and snapshots the files before validation. The main schema digest is B646B6B525F51ADF1BB2545F111FC8CA6E7AA6DD2F98948F1667D3695C06D958. Imports resolve only to these verified local snapshots; document-supplied schema locations and DTDs cannot trigger downloads. Input is limited to 16 MiB and depth 128, with at most 1,000 reported diagnostics. Reports identify the input length, input hash and schema hash. No Java or Saxon runtime is required for this lane.

The checked-in corpus contains all 26 independent examples from the official FA(3) sample archive, including corrections, advances, settlements, simplified invoices and foreign currencies. XSD success establishes structure only. It does not certify Polish tax treatment, authorize submission or establish KSeF acceptance. This national format has its own schema contract rather than an EN 16931 profile declaration.

Validate invoice XML

The configured stages are:

Download the official KoSIT rule archive and the pinned Apache-2.0 Factur-X/ZUGFeRD validator configuration, and extract the official SaxonJ-HE 12.10 distribution to a local tools directory. Keep Saxon's lib directory next to its main JAR and provide a Java runtime. These external artifacts retain their upstream licenses; OfficeIMO does not redistribute the authority rules or Java runtime.

The runner verifies the main JAR and its xmlresolver-5.3.3.jar, xmlresolver-5.3.3-data.jar and jline-2.14.6.jar companions at construction and before execution. Each invocation runs from a private copy of those verified bytes, excluding installation-directory aliases and loose classes. Reports identify all four JAR hashes. The configured Java executable remains supplied and managed by the caller.

using OfficeIMO.Invoicing.Validation;

var bundle = InvoiceRuleBundle.Load(
    "xrechnung-3.0.2-validator-configuration-2026-08-31.zip",
    facturXArchivePath: "validator-configuration-zugferd.zip");
var runner = new SaxonInvoiceRulesRunner("tools/saxon/saxon-he-12.10.jar");
var validator = new InvoiceValidator(bundle, runner);
var report = await validator.ValidateAsync(
    File.ReadAllBytes("invoice.xml"),
    InvoiceSpecificationRelease.XRechnung_3_0_2_2026_08_31);

Console.WriteLine($"{report.IsValid}: {report.Sha256}");
foreach (var diagnostic in report.Diagnostics)
    Console.WriteLine($"{diagnostic.Code}: {diagnostic.Message}");

For Peppol, also supply the official 3.0.21 Schematron source as the second argument to InvoiceRuleBundle.Load. The source is verified by SHA-256 and compiled locally with the included MIT-licensed Schematron compiler. The Peppol download names an immutable official source commit; a changed artifact is rejected by its pinned hash.

Factur-X authoring and validation use release FacturX_1_09_2_Zugferd_2_5_2. The validator archive is pinned by commit and SHA-256. Its rules include the 2.5.2 CII-SR-470 creditor-account rule and EXTENDED's replacement item-attribute rules, optional VAT category on GROUP/INFORMATION lines, and rounded group subtotals. These are the rules effective from 1 September 2026. The separate EN 16931, XRechnung and Peppol releases keep their own pinned rules; select the intended release explicitly when validating an older contract. Independent producer fixtures from AdVitam/facturx cover all five profiles. The checked-in corpus manifest also pins KoSIT XRechnung CII and UBL fixture hashes. XRechnung is the only national CIUS exposed by the validator; recognizing another guideline does not create a validation contract without its own syntax, rules and corpus.

IsValid is true only when both XSD and business rules passed. Without a runner, business rules are NotRun. Engine failures are Failed, and content failures are Invalid. Reports include exact input length, SHA-256, release, authority artifact hash, immutable source, source commit when applicable, and runner identity. Factur-X reports identify the Factur-X bundle rather than the KoSIT bundle used by the EN 16931/XRechnung lanes. Revalidate after any edit to the XML. Runner identity is recorded after an invoice-rule process starts, including when that process fails. Startup failures and compiler-only executions leave it empty. Reports contain at most 999 detailed diagnostics plus a summary of excess diagnostics with their highest severity, preserving the distinction between invalid invoice content and a failed validator.

The pinned EN 16931 artifacts differ for zero-rated IGIC (category L): CII rules BR-AF-05/06/07 require a positive rate, while the UBL rules permit zero. The semantic model accepts a non-negative IGIC rate; the standards report exposes the selected syntax's rule result. A zero-rate CII invoice therefore cannot receive a passing report from this pinned release.

This validates XML. Factur-X/ZUGFeRD PDF/A, XMP, attachment relationships and visible invoice content require the separate PDF artifact checks. This package does not certify delivery over the Peppol network or the legality of a transaction.

Each rule-engine invocation uses a separate temporary workspace. On Unix, its permissions restrict access to the current user before invoice content is written. The workspace is removed after completion, failure, cancellation, or timeout.

Run the standards checks

With Java and the .NET 10 SDK available, run:

./Build/Test-InvoicingStandards.ps1

The command downloads hash-pinned authority artifacts, the independent producer corpus and Saxon into artifacts/invoicing-standards, then validates generated documents and independent fixtures. It validates all five generated and independent Factur-X profiles plus the declared XRechnung and Peppol lanes. -OutputPath selects a different local artifact directory; -JavaExecutable selects an existing Java installation. The artifacts remain there for reuse and inspection.