ClarkBook

HTML to PDF and image using WebAssembly, powered by plutobook — a robust HTML rendering library for paged media. Does not depend on Chromium, WebKit, or Gecko.

Install

npm install clarkbook

Usage

import { createBook, PageSize, Margins } from "clarkbook";

const book = await createBook();

// Render to PDF
const pdf = book.pdf("<h1>Hello</h1>", {
  pageSize: PageSize.A4,
  margins: Margins.Normal,
});

// Render to image
const image = book.image("<h1>Hello</h1>", {
  format: "png",
  width: 1200,
  height: 800,
});

Custom fonts

import { readFile } from "node:fs/promises";

const book = await createBook({
  fonts: [
    ["Inter.ttf", await readFile("./Inter.ttf")],
  ],
});

Next.js

import path from "node:path";
import { createBook } from "clarkbook";
import { NextResponse } from "next/server";
import fs from "node:fs/promises";

const fontFile = path.join(
  process.cwd(),
  "app/fonts/GoogleSans-VariableFont_GRAD,opsz,wght.ttf",
);

const book = await createBook({
  fonts: [["GoogleSans.ttf", await fs.readFile(fontFile)]],
});

export async function GET() {
  const buffer = book.image("<h1>Hello, world</h1>", {
    format: "jpeg",
  });

  return new NextResponse(new Uint8Array(buffer), {
    status: 200,
    headers: {
      "Content-Type": "image/jpeg",
      "Content-Disposition": 'inline; filename="document.jpg"',
    },
  });
}

Resources

Pass additional assets (images, stylesheets) via resources:

const pdf = book.pdf(html, {
  resources: {
    "https://example.com/style.css": await readFile("./style.css"),
  },
  baseUrl: "https://example.com/",
});

API

createBook(options?)

| Option | Type | Description | | ------- | --------------------------------- | -------------------- | | fonts | [name: string, data: Uint8Array][] | Custom font files |

Returns a Book instance.

book.pdf(html, options?)

| Option | Type | Default | | ----------- | ----------------------- | --------------- | | pageSize | [number, number] | PageSize.A4 | | margins | [number, number, number, number] | Margins.Normal | | resources | Record<string, Uint8Array> | {} | | userStyle | string | "" | | baseUrl | string | "" |

Returns Uint8Array.

book.image(html, options?)

Extends pdf options with:

| Option | Type | Default | | --------- | ----------------------------- | -------- | | format | "png" \| "jpeg" \| "webp" | "png" | | width | number | -1 | | height | number | -1 | | quality | number | 90 |

Returns Uint8Array.

PageSize

A3, A4, A5, B4, B5, Letter, Legal, Ledger

Margins

None, Narrow, Normal, Moderate, Wide

License

MPL-2.0

Credits

Built on plutobook by the plutoprint project.