Add XFA support to AcroForm module

[dsolankii]

Summary

• add addXFA entry point to embed XFA payloads and toggle NeedRendering
• normalize stream/array inputs, emit XFA packets during document build, and keep AcroForm fallbacks intact
• add regression coverage and extend TypeScript typings for the new API

Testing

• npm run build
• npm run test-unit
• npm run test-node
• npm run test-amd
• npm run test-esm
• npm run test-globals
• npm run test-typescript
• npm run test-webworker

Closes #3886

(Friendly note: I’m participating in Hacktoberfest—thanks for tagging or merging!)

[JDziurlaj]

Thank you for working on this! There is one typo that is causing issues, otherwise LGTM! (Looking back at the originating issue, the typo was mine! 😳)

[JDziurlaj]

Should be NeedsRendering (plural). Check and fix throughout PR.

[dsolankii]

Thanks for catching that! I’ve updated the code/tests to use /NeedsRendering and pushed the change.

[HackbrettXXX]

Thanks for this PR. I'm no expert regarding XFA, but the code generally looks good. Could you add a test case that creates/compares a PDF with a reference, so I can check if the created PDF works.

[HackbrettXXX]

I think we should also rename this field to "needsRendering"

[dsolankii]

Thanks for the review! I’ve renamed the internal flag to needsRendering and added a regression test in test/specs/acroform.spec.js (it("addXFA generates expected PDF")) that compares the generated file against the new reference test/reference/xfa-basic.pdf.

You can reproduce it with:

npm run test-unit -- --grep "addXFA generates expected PDF" --reporters mocha

The reference PDF contains /NeedsRendering true in the catalog and the /XFA [(datasets) … (template) …] packets (verified via qpdf --qdf --object-streams=disable test/reference/xfa-basic.pdf -). Happy to adjust anything else!

[HackbrettXXX]

When I open the xfa-basic.pdf file in Adobe Reader, there is an error message:

Xml parsing error: junk after document element (error code 0), line 1, column 12 of file

[JDziurlaj]

The test example isn't a minimally valid XDP. I can provide one for you.

[JDziurlaj]

Try this:

var doc = new jsPDF();
doc.text("If you are reading this, your viewer doesn't support XFA Forms!",20,20)
var payload = `
<xdp:xdp xmlns:xdp="http://ns.adobe.com/xdp/">
  <template xmlns="http://www.xfa.org/schema/xfa-template/3.6/">
    <subform name="form1" layout="tb" locale="en_US">
      <pageSet>
        <pageArea name="Page1" id="Page1">
          <contentArea x="0.25in" y="0.25in" w="576pt" h="756pt"/>
          <medium stock="default" short="612pt" long="792pt"/>
        </pageArea>
      </pageSet>
      <subform w="576pt" h="756pt">
        <draw name="Text1" w="8in" h="56.88mm">
          <ui>
            <textEdit/>
          </ui>
          <value>
            <text>If you are reading this, your viewer supports XFA Forms!</text>
          </value>
          <font size="48pt" typeface="Myriad Pro" baselineShift="0pt"/>
          <margin topInset="0.5mm" bottomInset="0.5mm" leftInset="0.5mm" rightInset="0.5mm"/>
          <para hAlign="center" spaceAbove="0pt" spaceBelow="0pt" textIndent="0pt" marginLeft="0pt" marginRight="0pt"/>
        </draw>
      </subform>
      <proto/>
    </subform>
  </template>
</xdp:xdp>`;

// Inject the XFA payload into the current PDF
doc.addXFA(payload, true);