pdfkit-commonmark

Allows users of pdfkit to render commonmark style markdown into their document (see usage/code).

Renders commonmark style markdown to pdf (see usage/cli).

Info

It relies on the abstract syntax tree created by the commonmark parser to create a custom renderer using pdfkit. To facilitate unit testing, the AST gets transformed into an intermediate (testable) list of operations which will finally be transformed into pdfkit api calls.

The PDF version of this README has been created using the pdfkit-commonmark cli script.

Install

Installation uses the npm package manager. Just type the following command after installing npm.

npm install --save pdfkit-commonmark

Supported markdown features

Paragraphs

Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua.

Duis autem vel eum iriure dolor in hendrerit in vulputate velit esse molestie consequat, vel illum dolore eu feugiat nulla facilisis at vero eros et accumsan et iusto odio dignissim qui blandit praesent luptatum zzril delenit augue duis dolore te feugait nulla facilisi.

Headers (level 3)

Level 4

Level 5

Emphasize, Strong and Links

Lorem ipsum dolor sit amet, consetetur sadipscin. source

Softbreaks (compare pdf with markdown source)

Duis autem vel eum iriure dolor in hendrerit in vulputate velit esse molestie consequat, vel illum dolore eu feugiat nulla facilisis at vero eros et accumsan et iusto odio dignissim qui blandit praesent luptatum zzril delenit augue duis dolore te feugait nulla facilisi.

Linebreaks (two spaces at the end of the line)

Duis autem vel eum iriure dolor in
hendrerit in vulputate velit esse
molestie consequat, vel illum dolore
eu feugiat nulla facilisis at vero
eros et accumsan et iusto odio
dignissim qui blandit praesent
luptatum zzril delenit augue duis
dolore te feugait nulla facilisi.

Horizontal rules

Lists

• paragraphs
• headers
• inline formatting
  1. emphasize
  2. strong
  3. links
• softbreaks
• explicit linebreaks
• horizontal rules
• lists, including
  multi-line with
  formatting and links
• and last but not least
  1. nested lists
  2. and ordered lists

Unsupported markdown features

This renderer currently does not support:

• block quotes
• images
• html
• tables

Pull requests to fill in these features are welcome.

Usage

CLI

pdfkit-commonmark <inputFile> [<outputFile>]

Code

import commonmark from 'commonmark';
import CommonmarkPDFRenderer from 'pdfkit-commonmark';
import PDFDocument from 'pdfkit';

// get parser instance
const reader = new commonmark.Parser();

// parse input
const parsed = reader.parse('This is **markdown** formatted text.');

// get pdf renderer instance
const writer = new CommonmarkPDFRenderer();

// create pdf document
const doc = new PDFDocument();

// write pdf to some file in the current directory
doc.pipe(fs.createWriteStream(__dirname + '/test.pdf'));

// render parsed markdown to pdf
writer.render(doc, parsed);

// end the document
doc.end();

Dependencies

commonmark and pdfkit are marked as peerDependencies. Technically you would not need either of them for this module to work properly. But it would be pretty pointless to do so.