@imprint-pdf/ua

Tagged PDF and PDF/UA-1 accessible output for imprint-pdf.

Mandated by the EU European Accessibility Act (EAA, in force June 2025) and US Section 508. This package makes imprint-pdf's output machine-verifiable against PDF/UA-1 (ISO 14289-1).

License: Apache-2.0. See LICENSING.md.

pnpm add @imprint-pdf/ua

What it adds

• PDF structure tree. StructElem dictionaries (H1–H6, P, Table, Figure, Link, etc.) built from the reconciler IR.
• MarkInfo + ViewerPreferences. Marked: true and DisplayDocTitle: true required by PDF/UA-1 §7.1.
• Alt text. Reads JSX alt, aria-label, and title props from image and SVG nodes.
• Language. <Document lang="en-US"> sets /Lang on the catalog.
• Pre-render IR validation. validateUA reports missing lang, missing title, and images without alt text before a byte of PDF is written.

Usage

Wire up the postProcess hook

import { pdf } from '@imprint-pdf/react';
import { taggedPdf } from '@imprint-pdf/ua';

const response = await pdf(
  <Document lang="en-US" title="Q1 Report">
    <Page size="A4" className="p-12">
      <h1 className="text-3xl font-bold">Accessible PDF</h1>
      <img src={logoUrl} alt="Acme Corp logo" className="mt-4 h-16" />
    </Page>
  </Document>,
  { postProcess: [taggedPdf()] },
);

Validate the IR before rendering

import { validateUA } from '@imprint-pdf/ua';

const result = validateUA(documentNode);
if (!result.valid) {
  console.error(result.errors); // missing lang, missing alt, etc.
}

Validation in CI

imprint validate ./dist/report.pdf --profile pdf-ua-1
# → veraPDF reports pass/fail; exits non-zero on any failure

Low-level helpers

| Export | What it does | | ----------------------- | ------------------------------------------------------- | | taggedPdf() | postProcess hook — writes structure tree + catalog | | applyStructTree | Applies the structure tree to an existing PDFDocument | | validateUA | Walks an IR tree and returns errors + warnings | | validateUAConformance | Subset alias kept for CLI --profile pdf-ua-1 compat | | isTextLeaf | Type predicate — node carries user-visible text | | HTML_TO_ROLE | Map from HTML tag names to PDF structure roles |