Artigo técnico

PDFlibPas: PDF/A and PDF/UA preflight in Delphi

losLab PDF Library oferece a equipes Delphi e C++Builder um mecanismo PDF com codigo-fonte disponivel para fluxos desktop, servidor, DLL, ActiveX e Dylib, com verificacoes PDF/A e PDF/UA integradas, suporte PAdES e opcoes de renderizacao sem servico PDF externo.

Este artigo é para developers delivering archive-ready and accessibility-aware PDFs from Delphi systems. Ele trata PDF/A and PDF/UA preflight como engenharia documental de produção, não como uma chamada isolada de componente.

O risco prático é que PDF/A and PDF/UA failures usually reflect document design decisions, so late preflight without ownership produces lists of issues nobody can fix. Por isso o fluxo precisa de contrato escrito, diagnósticos observáveis e arquivos de regressão representativos.

Decisões de arquitetura

Connect preflight findings to template ownership. target PDF/A profile, PDF/UA expectations, and accepted validator set / font, metadata, color, annotation, form, and attachment policies

  • target PDF/A profile, PDF/UA expectations, and accepted validator set
  • font, metadata, color, annotation, form, and attachment policies
  • tag structure, heading order, table markup, alternate text, and artifacts
  • issue ownership and release-gate severity mapping

Fluxo de implementação

Treat diagnostics as product requirements. The order below keeps the workflow reviewable for Delphi and C++Builder teams.

  1. configure document generation around the target profiles before output
  2. run structured preflight and normalize findings by owner and severity
  3. route template issues to template maintainers and data issues to application owners
  4. rerun validation after each fix rather than relying on visual inspection
  5. ship the report with the document package when customers require evidence

Evidências de validação

Preflight evidence for archive and accessibility workflows. Keep these fields with the output or support record.

  • profile, validator version, issue code, severity, page, object, and owner
  • font embedding, output intent, metadata, and attachment findings
  • tagging diagnostics such as heading order, table structure, artifacts, and alternate text
  • release decision, waivers, and final pass or fail report

Archive and accessibility profiles ask different questions

PDF/A focuses on durable reproduction while PDF/UA focuses on semantic access. A production workflow should keep both validation profiles visible and assign findings to generation code, templates, or content owners.

Review questions before release

Before this reaches production, the team should be able to answer these questions without reading source code.

  • Who owns target PDF/A profile, PDF/UA expectations, and accepted validator set?
  • What evidence proves profile, validator version, issue code, severity, page, object, and owner?
  • What happens when an archive-valid file can still have poor reading order?
  • Which regression file covers ship the report with the document package when customers require evidence?

Engineering review notes for PDF/A and PDF/UA preflight

Use these review notes to make sure the feature has moved beyond a demo and can be defended during release, support, and customer escalation.

  • Decision: target PDF/A profile, PDF/UA expectations, and accepted validator set. Implementation pressure point: run structured preflight and normalize findings by owner and severity. Acceptance evidence: tagging diagnostics such as heading order, table structure, artifacts, and alternate text. Regression trigger: third-party inserted pages can break profile assumptions late in assembly
  • Decision: font, metadata, color, annotation, form, and attachment policies. Implementation pressure point: route template issues to template maintainers and data issues to application owners. Acceptance evidence: release decision, waivers, and final pass or fail report. Regression trigger: an archive-valid file can still have poor reading order
  • Decision: tag structure, heading order, table markup, alternate text, and artifacts. Implementation pressure point: rerun validation after each fix rather than relying on visual inspection. Acceptance evidence: profile, validator version, issue code, severity, page, object, and owner. Regression trigger: decorative content should be marked as artifacts instead of hidden visually only
  • Decision: issue ownership and release-gate severity mapping. Implementation pressure point: ship the report with the document package when customers require evidence. Acceptance evidence: font embedding, output intent, metadata, and attachment findings. Regression trigger: forms and annotations can conflict with archive goals depending on profile

Casos limite

  • an archive-valid file can still have poor reading order
  • decorative content should be marked as artifacts instead of hidden visually only
  • forms and annotations can conflict with archive goals depending on profile
  • third-party inserted pages can break profile assumptions late in assembly

Delphi / C++Builder notes

PDFlibPas should sit behind a small service boundary that receives files, streams, profiles, and credentials, then returns output paths, warnings, metrics, and validation status. Important terms include PDF/A, PDF/UA, CreatePreflightReportEx, accessibility, tag structure, validator.

Exemplo de código Delphi

O esboço Delphi abaixo mostra um limite de serviço prático para este tema. Mantenha checagens de política, logs e validação fora do trecho estreito que chama o produto para que o fluxo continue testável.

procedure RunStandardsPreflight(const InputFile, ReportFile: string; const Profile: string);
var
  Pdf: TPDFlib;
begin
  Pdf := TPDFlib.Create;
  try
    Pdf.LoadFromFile(InputFile, '');
    TFile.WriteAllText(ReportFile, BuildStandardsReport(Pdf, Profile), TEncoding.UTF8);
    FailOnBlockingStandardsIssues(ReportFile);
  finally
    Pdf.Free;
  end;
end;

Checklist de produção

  • Run the workflow on an empty file, a normal customer file, and a worst-case file
  • Open the generated PDF with the target viewer, validator, printer, or downstream application
  • Log product version, profile version, input hash, output path, elapsed time, and warning count
  • Keep passwords, certificates, temporary files, and customer data under explicit retention rules
  • Add regression documents when a customer file exposes a new edge case

Product documentation

PDFlibPas