Ruby On Rails SDK


Cloudinary is a cloud-based service that provides an end-to-end image and video management solution. The Ruby On Rails SDK provides simple, yet comprehensive image and video manipulation, optimization, and delivery capabilities that you can implement using code that integrates seamlessly with your existing Rails or Ruby application.

The Ruby on Rails SDK GEM may work well with a variety of Ruby and Rails versions.
It has been tested with Ruby 1.9, 2.2 and Rails 2.3.x, 3.0.x, 3.1.x, 3.2.x, 4.0.x.

Quick example: Transformations

The following Cloudinary URL and corresponding Ruby on Rails SDK code delivers the image below in an https delivery URL, including all of the following transformations:

  • Thumbnail crop to a size of 150x150 pixels using face detection gravity to automatically determine the location for the crop
  • Rounded corners with a 20 pixel radius
  • Sepia effect
  • Overlay of the Cloudinary logo on the southeast corner (with a slight offset). The logo is scaled down to a 50 pixel width, with increased brightness, and partial transparency (opacity = 60%)
  • Rotated by 10 degrees
  • Converted to and delivered in PNG format (the originally uploaded image was a JPG)

cl_image_tag("front_face.png", :secure=>true, :transformation=>[
  {:width=>150, :height=>150, :gravity=>"face", :radius=>20, :effect=>"sepia", :crop=>"thumb"},
  {:overlay=>"cloudinary_icon", :gravity=>"south_east", :x=>5, :y=>5, :width=>50, :opacity=>60, :effect=>"brightness:200"},
sample transformation

Quick example: File upload

The following Ruby code uploads the dog.mp4 video to the specified account sub-folder using the public_id, my_dog. The video will overwrite the existing my_dog video if it exists. When the video upload is complete, the specified notification URL will receive details about the uploaded media asset.

  :folder => "my_folder/my_sub_folder/", :public_id => "my_dog", :overwrite => true, 
  :notification_url => "", :resource_type => "video")

Ruby GEM features

Cloudinary provides a Ruby GEM (open source) that simplifies the integration with your Ruby and Ruby on Rails applications:

  • Build URLs for image and video manipulations
  • Rails view helper tags for embedding and transforming images
  • API wrappers: file upload, administration, sprite generation and more
  • Server-side file upload + direct unsigned file upload from the browser using the jQuery plugin
  • Migration tool
  • Active Record integration
  • CarrierWave plugin
  • Static image syncing for CDN delivery
  • General Ruby integration for non-Rails frameworks such as Sinatra

Ruby capitalization and data type guidelines

When using the Ruby on Rails SDK, keep these guidelines in mind:

  • Parameter names: snake_case. For example: public_id
  • Classes: PascalCase. For example: PictureUploader
  • Methods: snake_case. For example: cl_image_upload_tag
  • Pass parameter data as: Hash


Cloudinary's Ruby library is available as an open-source Ruby GEM.

To install the Cloudinary Ruby GEM, run:

gem install cloudinary

If you use Rails 3.x or later, edit your Gemfile, add the following line and run bundle.

gem 'cloudinary'

Or in Rails 2.x, edit your environment.rb and add:

config.gem 'cloudinary'


To use the Cloudinary Ruby on Rails library, you have to configure at least your cloud_name. Your api_key and api_secret are also needed for secure API calls to Cloudinary (e.g., image and video uploads). You can additionally define a number of optional configuration parameters if relevant. You can find your account-specific configuration credentials in the dashboard of our Management Console.

Setting the configuration parameters can be done either programmatically in each call to a Cloudinary method or globally using a cloudinary.yml configuration file, located under the config directory of your Rails project.

You can download your customized cloudinary.yml configuration file through our Management Console.

Here's an example of a cloudinary.yml file:

  cloud_name: "sample"
  api_key: "874837483274837"
  api_secret: "a676b67565c6767a6767d6767f676fe1"
  secure: true
  cdn_subdomain: true

You can always override the values specified in cloudinary.yml by passing different values in specific Cloudinary calls.

Another configuration option is to use a Rails initializer file. You can place a file named cloudinary.rb in the /config/initializers folder of your Rails project. Here's some sample initializer code:

Cloudinary.config do |config|
  config.cloud_name = 'sample'
  config.api_key = '874837483274837'
  config.api_secret = 'a676b67565c6767a6767d6767f676fe1' = true
  config.cdn_subdomain = true

One last configuration option allows you to dynamically configure the cloud_name, api_key, and api_secret by defining the CLOUDINARY_URL environment variable. The configuration URL is available in the Management Console's dashboard of your account. When using Cloudinary through a PaaS add-on (e.g., Heroku), this environment variable is automatically defined in your deployment environment. Here's a sample value:


If you use more than one configuration option, the order of precedence is:
CLOUDINARY_URL -> cloud_name -> cloudinary.yml

Sample projects

For additional useful code samples and to learn how to integrate Cloudinary with your Rails applications, take a look at our Sample Projects.

  • Basic Ruby sample: Uploading local and remote images to Cloudinary and generating various transformation URLs.
  • Basic Rails sample: Uploading local and remote images in a Rails project while embedding various transformed images in a Rails web view.
  • Rails Photo Album: A fully working web application. It uses CarrierWave to manage images of an album model (database). Performs image uploading both from the server side and directly from the browser using a jQuery plugin.

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