html-pdf-client

html-pdf-client converts any webpage or element into a printable PDF entirely client-side using html2canvas and jsPDF.

Table of contents

• Getting started
  • CDN
  • Raw JS
  • NPM
  • Bower
  • Console
• Usage
  • Advanced usage
    • Workflow
    • Worker API
• Options
  • Page-breaks
    • Page-break settings
    • Page-break modes
    • Example usage
  • Image type and quality
• Progress tracking
• Dependencies
• Contributing
  • Issues
  • Tests
  • Pull requests
• Credits
• License

Getting started

NPM

Install html-pdf-client and its dependencies using NPM with npm install --save html-pdf-client (make sure to include .js in the package name).

Note: You can use NPM to create your project, but html-pdf-client will not run in Node.js, it must be run in a browser.

Bower

Install html-pdf-client and its dependencies using Bower with bower install --save html-pdf-client (make sure to include .js in the package name).

Usage

Once installed, html-pdf-client is ready to use. The following command will generate a PDF of #element-to-print and prompt the user to save the result:

var element = document.getElementById('element-to-print');
htmlPdfClient(element);

Advanced usage

Every step of html-pdf-client is configurable, using its new Promise-based API. If html-pdf-client is called without arguments, it will return a Worker object:

var worker = htmlPdfClient();  // Or:  var worker = new html2pdf.Worker;

This worker has methods that can be chained sequentially, as each Promise resolves, and allows insertion of your own intermediate functions between steps. A prerequisite system allows you to skip over mandatory steps (like canvas creation) without any trouble:

// This will implicitly create the canvas and PDF objects before saving.
var worker = htmlPdfClient().from(element).save();

Workflow

The basic workflow of html-pdf-client tasks (enforced by the prereq system) is:

.from() -> .toContainer() -> .toCanvas() -> .toImg() -> .toPdf() -> .save()

Worker API

A few aliases are also provided for convenience:

Options

html-pdf-client can be configured using an optional opt parameter:

var element = document.getElementById('element-to-print');
var opt = {
  margin:       1,
  filename:     'myfile.pdf',
  image:        { type: 'jpeg', quality: 0.98 },
  html2canvas:  { scale: 2 },
  jsPDF:        { unit: 'in', format: 'letter', orientation: 'portrait' }
};

// New Promise-based usage:
htmlPdfClient().set(opt).from(element).save();

// Old monolithic-style usage:
htmlPdfClient(element, opt);

The opt parameter has the following optional fields:

Page-breaks

html-pdf-client has the ability to automatically add page-breaks to clean up your document. Page-breaks can be added by CSS styles, set on individual elements using selectors, or avoided from breaking inside all elements (avoid-all mode).

By default, html-pdf-client will respect most CSS break-before, break-after, and break-inside rules, and also add page-breaks after any element with class htmlPdfClient__page-break (for legacy purposes).

Page-break settings

Page-break modes

Example usage

// Avoid page-breaks on all elements, and add one before #page2el.
htmlPdfClient().set({
  pagebreak: { mode: 'avoid-all', before: '#page2el' }
});

// Enable all 'modes', with no explicit elements.
htmlPdfClient().set({
  pagebreak: { mode: ['avoid-all', 'css', 'legacy'] }
});

// No modes, only explicit elements.
htmlPdfClient().set({
  pagebreak: { before: '.beforeClass', after: ['#after1', '#after2'], avoid: 'img' }
});

Image type and quality

You may customize the image type and quality exported from the canvas by setting the image option. This must be an object with the following fields:

These options are limited to the available settings for HTMLCanvasElement.toDataURL(), which ignores quality settings for 'png' images. To enable png image compression, try using the canvas-png-compression shim, which should be an in-place solution to enable png compression via the quality option.

Progress tracking

The Worker object returned by htmlPdfClient() has a built-in progress-tracking mechanism. It will be updated to allow a progress callback that will be called with each update, however it is currently a work-in-progress.

Dependencies

html-pdf-client depends on the external packages html2canvas, jsPDF, and es6-promise. These dependencies are automatically loaded when using NPM or the bundled package.

If using the unbundled dist/htmlPdfClient.min.js (or its un-minified version), you must also include each dependency. Order is important, otherwise html2canvas will be overridden by jsPDF's own internal implementation:

<script src="es6-promise.auto.min.js"></script>
<script src="jspdf.min.js"></script>
<script src="html2canvas.min.js"></script>
<script src="html2pdf.min.js"></script>

License

The MIT License

Copyright (c) 2019-2022 Pradeep Kumar Vishwakarma http://www.pv-dev.me