PDFKit Skill

PDFKit runs in the Electron main process only — never in the renderer. In this project, it lives at src/ipc/parsers/pdf-generator.ts and is invoked through the oRPC checklist.exportFile handler. PDFKit is a Node.js readable stream — pipe it to fs.createWriteStream() for file output or collect chunks into a Buffer.

Quick Start

Buffer-based export (for IPC handler)

import PDFDocument from "pdfkit";

export function generatePdf(file: ChecklistFile): Promise<Buffer> {
  return new Promise((resolve, reject) => {
    const doc = new PDFDocument({ size: "LETTER", margin: 50 });
    const chunks: Buffer[] = [];

    doc.on("data", (chunk: Buffer) => chunks.push(chunk));
    doc.on("end", () => resolve(Buffer.concat(chunks)));
    doc.on("error", reject);

    // Render content...
    doc.fontSize(20).text(file.name, { align: "center" });
    doc.end();
  });
}

File-based export (direct write)

import PDFDocument from "pdfkit";
import { createWriteStream } from "fs";

const doc = new PDFDocument({ size: "LETTER", bufferPages: true });
doc.pipe(createWriteStream(outputPath));
// ...render content...
doc.end();

Key Concepts

Built-in Fonts

PDFKit includes 14 standard PDF fonts — no font files needed:

Courier, Courier-Bold, Courier-Oblique, Courier-BoldOblique, Helvetica, Helvetica-Bold, Helvetica-Oblique, Helvetica-BoldOblique, Times-Roman, Times-Bold, Times-Italic, Times-BoldItalic, Symbol, ZapfDingbats

Common Patterns

Challenge/Response row with dot leader

function renderChallengeResponse(
  doc: InstanceType<typeof PDFDocument>,
  challenge: string,
  response: string,
  x: number,
  width: number,
) {
  const responseWidth = doc.widthOfString(response);
  const dotsWidth = 20;
  const challengeWidth = width - responseWidth - dotsWidth;

  doc.font("Helvetica").fontSize(11).text(challenge, x, doc.y, {
    width: challengeWidth,
    continued: true,
  });

  doc.font("Courier").fontSize(9).text(" .... ", { continued: true });

  doc.font("Helvetica-Bold").fontSize(11).text(response, { align: "right" });
}

Section header with colored bar

function renderSectionHeader(
  doc: InstanceType<typeof PDFDocument>,
  title: string,
  x: number,
  width: number,
) {
  const y = doc.y;
  doc.rect(x, y, 3, 14).fill("#a371f7");
  doc
    .font("Helvetica-Bold")
    .fontSize(11)
    .fillColor("#333333")
    .text(title.toUpperCase(), x + 10, y + 1, { width: width - 10 });
  doc.moveDown(0.3);
}

WARNING: ASAR Compatibility

PDFKit with custom fonts requires font files on disk. In Electron production builds, files inside ASAR archives can't be read by native Node.js fs. Use built-in fonts or bundle font files via electron-builder's extraResources.

See Also

• •patterns — Checklist rendering patterns, page layout
• •workflows — Export pipeline, IPC integration, testing

Related Skills

• •See the electron skill for main process and IPC patterns
• •See the orpc skill for the handler → router → action IPC pattern
• •See the zod skill for validating export handler inputs
• •See the fast-xml-parser skill for the sibling ACE parser

Documentation Resources

Fetch latest pdfkit documentation with Context7.

How to use Context7:

1. •Use mcp__context7__resolve-library-id to search for "pdfkit"
2. •Query with mcp__context7__query-docs using the resolved library ID

Library ID: /foliojs/pdfkit

Recommended Queries:

• •"pdfkit text styling fonts alignment"
• •"pdfkit page size margins addPage bufferPages"
• •"pdfkit vector graphics rect line stroke fill"
• •"pdfkit pipe to buffer stream"