url2png gem

What is it?

A Ruby gem wrapping the url2png.com API.

Who should use it?

Any Ruby on Rails developer who wants/needs to generate screenshots from sites using url2png.com.



gem install url2png


First define your public key and shared secret:

Url2png.api_key = 'PXXXXXXXXXXXXX'

You can define the api version if you want to use an older version of the url2png api.

Url2png.api_version = "v4"

Available versions:

  • v6 (default)
  • v4

If you are generating local urls in development you can use a placeholder or dummy image. This is done by setting the mode:

Url2png.mode = :placehold if Rails.env.development?

Options are:

  • :production (default; will use the url2png api to generate images)
  • :placehold (will generate images at http://placehold.it)
  • :dummy (will give a grey base64 data image)

In Rails you probably want to do configuration in an initializer.


Generate an image tag:

site_image_tag url, [options]

Options differ by version!

Version 6


Constrain screenshot based on width or height or both.
default: no resizing

= site_image_tag 'http://www.zwartopwit.com', :thumbnail_max_width => 500, :thumbnail_max_height => 500

Set viewport dimensions, adjust to your hearts content.
default: 1480x1037

= site_image_tag 'http://www.zwartopwit.com', :viewport => "1024x900"

Will attempt to capture entire document canvas.
default: false

= site_image_tag 'http://www.zwartopwit.com', :fullpage => true

Extra delay (in seconds) forced between page load and screenshot.
default: 1
min: 1
max: 5


site_image_tag url, :size => '300x200', :delay => 2

Forces a fresh screenshot with each request, overwriting the previous copy.
You will be charged for every request made using the force option.

= site_image_tag 'http://www.zwartopwit.com', :force => true

Version 4

By default the size is set to 400 x 400 px. To generate an image with a specific size:

site_image_tag url, :size => '300x200'

To only get the image url:

site_image_url url, :size => '300x200'

Options are:


This is a proportion bounding box.
Thumbnails will be resized to fit within this box.
default: 'ORIGINAL'

site_image_tag url, :size => '500x500'

site_image_tag url, :size => 'ORIGINAL'
Thumbnail (alias for :size)
Browser size

Set the initial browser screen size.
default: '1024x768'
min: '200x200'
max: '4000x4000'

site_image_tag url, :size => '300x200', :browser_size => '1024x2500'

Extra delay (in seconds) forced between page load and screenshot.
default: 1
min: 1
max: 5

site_image_tag url, :size => '300x200', :delay => 2

When true, Will attempt to capture entire document canvas.
Will never return screenshot smaller than "Initial Screen Size".
default: false


site_image_tag url, :size => '300x200', :fullscreen => true


This gem is written for Rails 3. Rails 2 might work but it's not tested.

Note that this gem is still under development.

Contributing to url2png

  • Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet
  • Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it
  • Fork the project
  • Start a feature/bugfix branch
  • Commit and push until you are happy with your contribution
  • Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.
  • Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.

Original API docs:


Copyright (c) 2011 Wout Fierens. See LICENSE.txt for further details.