PDFV8

A JavaScript PDF generation library for Cloudflare Workers (Edge).

Description

PDFV8 is a PDF document generation library designed to run on the Edge (Cloudflare Workers). The API embraces chainability, and includes both low level functions as well as abstractions for higher level functionality.

See the docs in docs/ and the Worker-focused setup in “Cloudflare Workers Usage” below.

Installation

Use npm, yarn, or bun package manager. Just type the following command:

# with npm
npm install cloudflare-pdf

# with yarn
yarn add cloudflare-pdf

# with bun
bun add cloudflare-pdf

Development

To run tests (Jest), use the package script so the correct runner is used:

npm test
# or with bun (use "bun run test", not "bun test")
bun run test

Features

• Vector graphics
  • HTML5 canvas-like API
  • Path operations
  • SVG path parser for easy path creation
  • Transformations
  • Linear and radial gradients
• Text
  • Line wrapping (with soft hyphen recognition)
  • Text alignments
  • Bulleted lists
• Font embedding
  • Supports TrueType (.ttf), OpenType (.otf), WOFF, WOFF2, TrueType Collections (.ttc), and Datafork TrueType (.dfont) fonts
  • Font subsetting
  • See fontkit for more details on advanced glyph layout support.
• Image embedding
  • Supports JPEG and PNG files (including indexed PNGs, and PNGs with transparency)
• Tables
• Annotations
  • Links
  • Notes
  • Highlights
  • Underlines
  • etc.
• AcroForms
• Outlines
• PDF security
  • Encryption
  • Access privileges (printing, copying, modifying, annotating, form filling, content accessibility, document assembly)
• Accessibility support (marked content, logical structure, Tagged PDF, PDF/UA)

Coming soon!

• Patterns fills
• Higher level APIs for laying out content
• More performance optimizations
• Even more awesomeness, perhaps written by you! Please fork this repository and send me pull requests.

Example (Cloudflare Workers)

const PDFDocument = require('cloudflare-pdf');

const doc = new PDFDocument();

// Collect output into an ArrayBuffer (Workers)
const chunks = [];
doc.on('data', (c) => chunks.push(c));
const pdfDone = new Promise((resolve) => doc.on('end', resolve));

// Embed a font, set the font size, and render some text
doc
  // Use standard fonts after preloading them (see below), or pass ArrayBuffer/Uint8Array for embedded fonts.
  .font('Helvetica-Bold')
  .fontSize(25)
  .text('Some text with an embedded font!', 100, 100);

// Add an image, constrain it to a given size, and center it vertically and horizontally
doc.image('path/to/image.png', {
  fit: [250, 300],
  align: 'center',
  valign: 'center'
});

// Add another page
doc
  .addPage()
  .fontSize(25)
  .text('Here is some vector graphics...', 100, 100);

// Draw a triangle
doc
  .save()
  .moveTo(100, 150)
  .lineTo(100, 250)
  .lineTo(200, 250)
  .fill('#FF3300');

// Apply some transforms and render an SVG path with the 'even-odd' fill rule
doc
  .scale(0.6)
  .translate(470, -380)
  .path('M 250,75 L 323,301 131,161 369,161 177,301 z')
  .fill('red', 'even-odd')
  .restore();

// Add some text with annotations
doc
  .addPage()
  .fillColor('blue')
  .text('Here is a link!', 100, 100)
  .underline(100, 100, 160, 27, { color: '#0000FF' })
  .link(100, 100, 160, 27, 'http://google.com/');

// Finalize PDF file
doc.end();

await pdfDone;
const pdf = new Blob(chunks, { type: 'application/pdf' });
return new Response(pdf, { headers: { 'content-type': 'application/pdf' } });

Cloudflare Workers Usage

• Standard fonts (Helvetica, Times, Courier, etc.) are not loaded by default. Preload them once at startup:

const StandardFont = require('cloudflare-pdf/lib/font/standard').default;
await StandardFont.preload(); // or await StandardFont.preload(['Helvetica', 'Helvetica-Bold'])

• Embedded fonts: pass ArrayBuffer/Uint8Array (for example from R2.get(...).arrayBuffer()).

In addition to PDFKit, you'll need somewhere to stream the output to. HTML5 has a Blob object which can be used to store binary data, and get URLs to this data in order to display PDF output inside an iframe, or upload to a server, etc. In order to get a Blob from the output of PDFKit, you can use the blob-stream module.

The following example uses Browserify or webpack to load PDFKit and blob-stream. See here and here for examples of prebuilt version usage.

// require dependencies
const PDFDocument = require('pdfkit');
const blobStream = require('blob-stream');

// create a document the same way as above
const doc = new PDFDocument();

// pipe the document to a blob
const stream = doc.pipe(blobStream());

// add your content to the document here, as usual

// get a blob when you are done
doc.end();
stream.on('finish', function() {
  // get a blob you can do whatever you like with
  const blob = stream.toBlob('application/pdf');

  // or get a blob URL for display in the browser
  const url = stream.toBlobURL('application/pdf');
  iframe.src = url;
});

You can see an interactive in-browser demo of PDFKit here.

This package targets Edge runtimes; Node filesystem APIs are not used at runtime.

Documentation

For complete API documentation and more examples, see the PDFKit website.

License

PDFKit is available under the MIT license.