/decktape

PDF exporter for HTML presentation frameworks

Primary LanguageJavaScript

DeckTape

DeckTape is a high-quality PDF exporter for HTML5 presentation frameworks.

DeckTape supports all the features that you would expect from a PDF exporter like font embedding, selectable text, hyperlinks, SVG graphics objects, file compression.

DeckTape is built on top of PhantomJS which relies on Qt WebKit for laying out and rendering Web pages and provides a headless WebKit scriptable with a JavaScript API.

DeckTape currently supports the following presentation frameworks out of the box:

 • Bespoke.js       • DZSlides         • remark           • Shower
 • CSSS             • Flowtime.js      • reveal.js        • Slidy
 • deck.js          • impress.js       • RISE             • WebSlides

DeckTape also provides a generic command that works by emulating the end-user interaction, allowing it to be used to convert presentations from virtually any kind of framework. The generic mode is particularly useful for supporting HTML presentation frameworks that don’t expose an API or accessible state.

DeckTape’s plugin-based architecture exposes an extension API, making it possible to add support for other frameworks or to tailor existing plugins to your specific needs.

DeckTape can optionally be used to capture screenshots of your slide decks in various resolutions (similar to pageres). That can be useful to make sure your presentations are responsive or to create handouts for them.

You can browse some slide deck examples below that have been exported with DeckTape.

Install

You can install DeckTape by downloading the source and executable manually from the latest release, or by executing the instructions below from the command-line:

  1. Download DeckTape source:

    $ curl -L https://github.com/astefanutti/decktape/archive/v1.0.0.tar.gz | tar -xz --exclude phantomjs

  2. Change into the decktape directory:

    $ cd decktape-1.0.0

  3. Download PhantomJS executable:

    ℹ️
    		 DeckTape currently depends on a forked version of PhantomJS. What follows is a list of pre-compiled binaries for various platforms. 
    # Windows (MSVC 2013), for Windows Vista or later, bundles VC++ Runtime 2013
$ curl -L https://github.com/astefanutti/decktape/releases/download/v1.0.0/phantomjs-msvc2013-x86.exe -o phantomjs.exe
# Mac OS X (Cocoa), 64-bit, for OS X 10.6 or later
$ curl -L https://github.com/astefanutti/decktape/releases/download/v1.0.0/phantomjs-osx-cocoa-x86-64 -o phantomjs
# Linux (static build), 64-bit, requires fontconfig (CentOS) or libfontconfig (Debian, Ubuntu)
$ curl -L https://github.com/astefanutti/decktape/releases/download/v1.0.0/phantomjs-linux-x86-64 -o phantomjs

  4. Set the execute permission (non-Windows OS binaries only):

    $ chmod +x phantomjs

If the executable isn’t available for your target platform, follow the instructions in the Build section. Alternatively, DeckTape provides a Docker image so that you can directly execute it with Docker. See the Docker section for more information.

Usage

Inside the DeckTape install directory, run:

$ ./phantomjs decktape.js -h

Usage: phantomjs decktape.js [options] [command] <url> <filename>

command      one of: automatic, bespoke, csss, deck, dzslides, flowtime, generic, impress,
             remark, reveal, shower, slidy, webslides
url          URL of the slides deck
filename     Filename of the output PDF file

Options:
   -s <size>, --size <size>        Size of the slides deck viewport: <width>x<height>  (ex. 1280x720)
   -p <ms>, --pause <ms>           Duration in milliseconds before each slide is exported  [1000]
   --load-pause <ms>               Duration in milliseconds between the page has loaded
                                   and starting to export slides  [0]
   --screenshots                   Capture each slide as an image  [false]
   --screenshots-directory <dir>   Screenshots output directory  [screenshots]
   --screenshots-size <size>       Screenshots resolution, can be repeated  [--size]
   --screenshots-format <format>   Screenshots image format, one of [jpg, png]  [png]
   --slides <range>                Range of slides to be exported, a combination of slide indexes
                                   and ranges (e.g. '1-3,5,8')

Defaults to the automatic command.
Iterates over the available plugins, picks the compatible one for presentation at the
specified <url> and uses it to export and write the PDF into the specified <filename>.

In addition to the general options listed above, command specific options can be displayed the following way:

$ ./phantomjs decktape.js <command> -h

Commands

automatic

Iterates over the available plugins, picks the compatible one for presentation at the specified url and uses it to export and write the PDF into the specified filename.

generic

Emulates the end-user interaction by pressing the key with the specified --keycode option and iterates over the presentation as long as:

  1. Any change to the DOM is detected by observing mutation events targeting the body element and its subtree nor

  2. the number of slides exported has reached the specified --max-slides option.

The --keycode value must be one of the PhantomJS page event keys and defaults to Right, e.g.:

$ ./phantomjs decktape.js generic --keycode=Space

webslides

PhantomJS doesn’t support flexbox very well and WebSlides makes heavy use of flexbox. For DeckTape to print WebSlides properly, it’ll need the right vendor prefixes on the flexbox attributes.

In base.css line 3147 change display: block !important; to display: flex: !important and run base.css through https://autoprefixer.github.io/ with filter safari >= 4.

For more info why the vendor prefixes are necessary, check the Issue on WebSlides or the Issue on PhantomJS. PhantomJS 2.5 will support flexbox. The prefixing of the CSS will be unnecessary once PhantomJS v2.5 has been released and the DeckTape fork has been rebased on v2.5.

Options

--screenshots

Captures each slide as an image at the --screenshots-size resolution, exports it to the --screenshots-format image format and writes the output into the --screenshots-directory directory.

The --screenshots-size option can be set multiple times. For example:

$ ./phantomjs decktape.js --screenshots --screenshots-size=400x300 --screenshots-size=800x600

--slides

Exports only the slides specified as a series of slides indexes and ranges, e.g.:

# Capture a single slide
$ ./phantomjs decktape.js --slides 1
# Capture a series of slides
$ ./phantomjs decktape.js --slides 1,3,5
# Capture a range of slides
$ ./phantomjs decktape.js --slides 1-10
# Capture a combination of slides and ranges
$ ./phantomjs decktape.js --slides 1,2,5-10

The rendering stops and the file written out after the largest numbered slide is exported.

Examples

The following slide deck examples have been exported using DeckTape:

HTML5 Presentation Framework Exported PDF

Beyond Rectangles in Web Design

reveal.js 2.6.2

fowd-nyc-2014.pdf (14MB)

Getting Involved in Open Source

reveal.js 3.0.0

opensource-getting-involved.pdf (0.8MB)

Going Further with CDI

Asciidoctor + DZSlides

going-further-with-cdi.pdf (1.8MB)

Transactions for the REST of us

impress.js 0.5.3

soa-cloud-rest-tcc.pdf (10MB)

Deck.js Modern HTML Presentations

deck.js 1.1.0

deck-js-presentation.pdf (1.1MB)

Flowtime.js Presentation Framework

Flowtime.js

flowtime-js-presentation.pdf (7.5MB)

The Official Remark Slideshow

remark 0.11.0

remark-js-slideshow.pdf (0.7MB)

HTML Slidy: Slide Shows in HTML and XHTML

Slidy

html-slidy-presentation.pdf (0.5MB)

CSSS: CSS-based SlideShow System

CSSS

csss-sample-slideshow.pdf (13.5MB)

Shower Presentation Engine

Shower

shower-presentation-engine.pdf (0.4MB)

Welcome our new ES5 Overloards

Bespoke.js

new-es5-overloards.pdf (0.1MB)

Docker

DeckTape can be executed within a Docker container from the command-line using the astefanutti/decktape Docker image available on Docker Hub:

$ docker run astefanutti/decktape -h

For example:

  • To convert an online HTML presentation and have it exported into the working directory under the slides.pdf filename:

    $ docker run --rm -v `pwd`:/slides astefanutti/decktape http://lab.hakim.se/reveal-js slides.pdf

  • Or, to convert an HTML presentation that’s stored on the local file system in the home directory:

    $ docker run --rm -v `pwd`:/slides -v ~:/home/user astefanutti/decktape /home/user/slides.html slides.pdf

  • Or, to convert an HTML presentation that’s deployed on the local host:

    $ docker run --rm --net=host -v `pwd`:/slides astefanutti/decktape http://localhost:8000 slides.pdf

You may want to specify a tag corresponding to a released version of DeckTape for the Docker image, e.g. astefanutti/decktape:1.0.0.

Besides, it is recommended to use the following options from the docker run command:

--rm

DeckTape is meant to be run as a short-term foreground process so that it’s not necessary to have the container’s file system persisted after DeckTape exits,

-v

to mount a data volume so that DeckTape can directly write to the local file system.

Alternatively, you can use the docker cp command, e.g.:

# Run docker run without the --rm option
$ docker run astefanutti/decktape http://lab.hakim.se/reveal-js slides.pdf
# Copy the exported PDF from the latest used container to the local file system
$ docker cp `docker ps -lq`:decktape/slides.pdf .
# Finally remove the latest used container
$ docker rm `docker ps -lq`

Finally, if you want to execute DeckTape using a local clone of the DeckTape repository in order to take your changes into account, you can run:

$ docker run --rm -v `pwd`:`pwd` -w `pwd` astefanutti/decktape slides.html slides.pdf

PhantomJS

Overview

DeckTape relies on a forked version of PhantomJS, which is maintained as a submodule of this project. The fork primarily adds a printer API to PhantomJS that allows DeckTape to generate a multi-page PDF document. By default, PhantomJS can only produce a single-page PDF for each capture.

Status

Our goal is to get all the patches from this fork merged into the upstream so the fork is no longer required.

The following table documents the patches we’ve made to PhantomJS and tracks the status of getting them merged into the upstream project.

Description Reference to Patch Merge Status

Printer module API

astefanutti/phantomjs@f0259c9

❗ todo

Add support for capturing viewport when rendering images (required to capture snapshots properly) ariya/phantomjs#10619

ariya/phantomjs@bfccbd6

✅ merged

Enable outline annotations to be rendered outside printing context (required for clickable hyperlinks with the printer module)

astefanutti/qtwebkit@9f8fd88

❕ todo

Render anchors as clickable links in PDF documents QTBUG-44563

qt/qtwebkit@62dd2ad

✅ merged

Add support for drawing a hyperlink in QPdfEngine QTBUG-44563

qt/qtbase@e9eeb68

✅ merged

Web fonts are not embedded in PDF on Linux and render as vector outlines QTBUG-52417 ariya/phantomjs#13997

astefanutti/qtbase@cf12105

❕ todo

Build

To build the forked version of PhantomJS for DeckTape, you have to execute the following commands:

  1. Clone the phantomjs repository:

    $ git clone https://github.com/astefanutti/phantomjs.git

  2. Change into the phantomjs directory:

    $ cd phantomjs

  3. Launch the build script:

    $ ./build.py

More information can be found in Compiling PhantomJS from source and in Building Qt 5 from Git.

Plugin API

✏️