pdfmake-html-renderer

JavaScript/HTML renderer for pdfmake PDF document definition objects.

Usage no npm install needed!

<script type="module">
  import pdfmakeHtmlRenderer from 'https://cdn.skypack.dev/pdfmake-html-renderer';
</script>

README

pdfmake-html-renderer

JavaScript/HTML renderer for pdfmake PDF document definition objects.

Playground: https://kryops.github.io/pdfmake-html-renderer/

What this library is for

  • Seamlessly embedding pdfmake document previews into web applications
  • Fast preview generation and incremental updates, e.g. for editor scenarios or frequent changes
  • Lightweight alternative to the full pdfmake when rendering document previews on the client (50-110KB minified compared to 2MB)

Limitations

  • Paging is not implemented: The document is rendered as a single page
    • Header and footer are rendered at the very top and the very bottom
    • Watermark and background are rendered only once at the top
    • Elements positioned through absolutePosition are positioned in reference to the top
    • Page references are rendered as X
    • linkToPage properties are ignored
    • The table of contents does not render page numbers
    • Manual page breaks specified through pageBreak: 'before' or pageBreak: 'after' are rendered as a horizontal line
    • For short content, we enforce the height of a single page (unless mode: 'fluid' is set)
  • Style inheritance may not work the same way as in pdfmake for every property
    • We apply backgrounds to the container, while pdfmake may pass them to the children in some cases (e.g. within lists)
  • Column widths behave slightly differently, especially when combining * and auto widths
  • Relative positioning ignores the alignment property
  • List markers in ordered lists are right-aligned, while pdfmake aligns them to the left
  • Empty elements or elements containing only spaces may be rendered differently in some cases
  • QR Codes look slightly different to the ones created by pdfmake

Supported browsers

Currently, only evergreen browsers are supported explicitly (see .browserslistrc).

If you need to support older browsers with your application, you should be able to run this library through Babel as part of your build process and polyfill newer APIs through core-js.

On old browsers that do not support CSS variables, some styles may be broken.

Usage

  1. Install this package:
npm install pdfmake-html-renderer
  1. Add the CSS file:
import 'pdfmake-html-renderer/dist/index.css';

NOTE: For this to work, make sure your tooling/bundler supports importing CSS files. Otherwise, you can always use a <link rel="stylesheet"> in your HTML file.

  1. (Optional) Import fonts:

Any fonts used in your PDF document definitions, including the default Roboto font, should be imported using CSS @font-face rules.

To use the version provided by Google Fonts, add the following HTML to your <head>:

<link rel="preconnect" href="https://fonts.gstatic.com">
<link href="https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,400;0,700;1,400;1,700&display=swap" rel="stylesheet">

Otherwise, the renderer may use a fallback font depending on the fonts installed on the machine.

  1. If you have a Content Security Policy, you might need to extend it:
  • style-src 'unsafe-inline' as computed styles are set inline
  • image-src data: for images passed as data URL
  1. Integrate the component:
import { PdfmakeHtmlRenderer } from 'pdfmake-html-renderer'

This library was built using the Svelte framework, which should allow integrating it into pretty much any web application:

Check out the /examples folder for some example projects.

TIP: If you don't need QR Code support, you can try and ignore the qrcode package in your build process / bundler. This will roughly cut this package's bundle size in half.

TypeScript support

This package provides TypeScript typings. They depend on the typings for svelte and pdfmake, which are not included as dependencies and need to be added manually:

npm install -D svelte @types/pdfmake

Node.js server-side rendering [EXPERIMENTAL]

This library also provides an experimental server build that renders static HTML and CSS:

const { PdfmakeHtmlRenderer } = require('pdfmake-html-renderer/server')

const { html, css } = PdfmakeHtmlRenderer.render({
    document: { content: ['Hello, world!'] }
});

// html contains the HTML code
// css.code contains the CSS code

Check out /examples/nodejs for an exmaple.

Rendering on the server comes with some additional limitations:

  • QR codes are not supported
  • Zooming / shrinking the page does not work
  • Relative positioning may not always be placed correctly

Options / Props

document: TDocumentDefinitions

The pdfmake document definition

pageShadow?: boolean

Whether or not to display a shadow around the page.

Defaults to true

mode?: 'shrinkToFit' | 'zoomToFit' | 'natural' | 'fluid'

Rendering / sizing mode

  • shrinkToFit (default): Shrinks the document to fit in its container, but does not grow beyond the document's natural size
  • zoomToFit: Shrinks or grows the document to fit in its container
  • natural: Renders the document in its exact natural size
  • fluid: Ignores the document's pageSize and uses the space available in the container

When the document definition does not specify a pageSize property, the standard size 'A4' is assumed.