How to turn your rails site into an OAuth Provider

Published November 26th, 2007 edit replace rm!

This has been updated on July 21st, 2009 to reflect all the latest changes*

OAuth is the great new standard allowing your users to use your application to talk to their accounts on other applications. I won’t go more into it here as it’s pretty well covered on the OAuth site.

I have created an OAuth Rails Plugin and an oauth gem which will help you to create both oauth providers and consumers.

Consumers and Providers

I will cover consumers in another post, but it’s probably a good idea to explain what the difference is:

A consumer is an application that uses another web applications data. For example for a mashup. It is mainly intended for web applications, but there is nothing to stop you from writing say a way cool Mac client in Cocoa as well.

A provider is a web application that the consumer wants to access.

The classic example is a photo printing site as a consumer and a photo site (like Flickr) as the provider.

Provider features

The plugin can generate an oauth provider that supports the following out of the box:

  • User can register their own applications to receive consumer key/secret pairs.
  • Provider supports standard best practises out of the box hmac-sha1 etc.
  • Users can manage and revoke tokens issued in their name
  • Easy before filter to provide oauth protection on your actions

Install the plugin

This plugin currently requires Rails 2. If someone would like to make it Rails 1.2 compatible. Please feel free to submit patches.

First install the oauth gem:

sudo gem install oauth

The plugin can now be installed as an gem from github, which is the easiest way to keep it up to date.

sudo gem install oauth-plugin

You should add the following in the gem dependency section of environment.rb

config.gem "oauth"
config.gem "oauth-plugin"

Alternatively you can install it in vendors/plugin:

script/plugin install git://

You also need an authentication plugin that is compatible with acts_as_authenticated, restful_authentication or restful_openid_authentication.

Lets create your provider

The generator creates 2 controllers a set of models and views.


script/generate oauth_provider

You now need to add a few associations to your user object:

has_many :client_applications
has_many :tokens, :class_name=>"OauthToken",:order=>"authorized_at desc",:include=>[:client_application]

Now run your migrations and start your server:

rake db:migrate

And your oauth provider is now up and running on http://localhost:3000/oauth_clients to start registering a client application.

Protect your actions

I recommend that you think about what your users would want to provide access to and limit oauth for those only. For example in a CRUD controller you may think about if you want to let consumer applications do the create, update or delete actions. For your application this might make sense, but for others maybe not.

If you want to give oauth access to everything a registered user can do, just replace the filter you have in your controllers with:

before_filter :login_or_oauth_required

If you want to restrict consumers to the index and show methods of your controller do the following:

before_filter :login_required,:except=>[:show,:index]
before_filter :login_or_oauth_required,:only=>[:show,:index]

If you have an action you only want used via oauth:

before_filter :oauth_required

All of these places the tokens user in current_user as you would expect.

Please bear in mind this is still early days and their maybe some major bugs and or changes coming. But please help me test the code.

There are also 2 other implementations:

  • Choon Keat’s OAuth4R which is a rails plugin for both creating providers and consumers. Choon and I are talking about how we can merge things.

If your company needs help getting your OAuth Strategy right or implementing OAuth in your application I’m available for consulting work [email protected].


choonkeat November 26th, 2007

Hi Pelle,

Very happy the Ruby/Rails side of things are finally progressing!

Unfortunately, for the routes, the only support for generators seem to only generate restful routes . You will need to copy-paste the function and customize locally.

sergiu November 26th, 2007

how is OAuth different than OpenID?

Pelle November 26th, 2007

I feared as much. Maybe I’ll do a patch to rails. I’ve already got a patch through in that area.

Pelle November 26th, 2007


OpenID and OAuth er complimentary technologies that server 2 very different purposes.

OpenID is used for users to identify themselves and login interactively to various web services. So Browser to Server.

OAuth is used by a user to give Server A permissions to use the users data on Server B. So Delegated Server to Server.

I know it can be a bit confusing. It took me a while to completely understand it.

sergiu November 27th, 2007

I’ve read a few examples about OAuth so now it’s much clear. It’s great having it as a Rails plugin, thanks for doing this.

jk February 4th, 2008

May I ask what is the time frame on the consumer generator or tutorial?

Shane V. February 8th, 2008

Eagerly awaiting the Consumer post… :) Great gem btw.

Pelle February 8th, 2008

I guess, I’ll have to write it then ;-)

If you want to get started have a look at the OAuth Gem RDoc, which apparently isn’t linked from the main site.

The only 3 classes you need to worry about are:

  • OAuth::Consumer
  • OAuth::RequestToken
  • OAuth::AccessToken

The basic flow is that you configure an instance of OAuth::Consumer with the details the service provider (say Twitter or Agree2 gives you).

(Hint Agree2 actually generates a code snippet for you)

I digress…

<pre><code> "key","secret",{:site=&gt;""} @request_token=consumer.get_request_token
redirect_to request_token.authentication_url @access_token=request_token.getAccessToken


The plan is to create a generator in the plugin that creates a controller and a set of models to manage this whole process with your users.

I am also in touch with Daniel who is working on integrating this into ActiveResource.

Corey July 17th, 2008

I am a Rails Noob, so please pardon me if I ask any obvious questions. With that said…after I perform the rake db:migrate towards the top of this ‘tutorial’, and I try to do the next step: “And your oauth provider is now up and running on http://localhost:3000/oauth to start registering a client application.”, I am getting an “undefined method ‘login_required’ for #OauthController….”

Am I missing something? Any ideas to help me along would be much appreciated!

Pelle July 17th, 2008

It sounds like you’re missing one of the authentication plugins above.

My recommendation is restful_authentication

Dave August 4th, 2008

HI Pelle,

Another newbie. Getting the same error as Corey. I have the restful_authentication plugin installed/ Do I need to run “./script/generate authenticated …” before I run your generator?

Pelle Braendgaard August 5th, 2008

Yes you’re right you need to fully install the plugin and generate it’s code first.


Santosh September 8th, 2008

your oauth provider is now up and running on http://localhost:3000/oauth to start registering a client application.”, I am getting an "undefined local variable or method `current_user’ for #<OauthController:0×4839b8c>
" error.

altough i am getting the registration screen for the url http://localhost:3000/oauth/new. but getting the same error on hitting the create button.

how are we going to initialize current_user. do we need to make the authentication module of our own?

Pelle Braendgaard September 8th, 2008

You need to fully install one of the authentication plugins first as mentioned above.

Santosh September 10th, 2008

i installed the restful_authentication pluggin, and folled the steps stated by you. now on firing the url http://localhost:3000/oauth, i am getting this error “undefined method `login_required’ for #<OauthController:0×487d7d8>”

Tyler October 26th, 2008

Great resource, I added it to the Netflix Resource center at

puran December 5th, 2008


I am new to this and getting below errro after follow up with all the stpes mentioned above, but still tillte bit doubt for :

You also need to add a few associations to your user object:

has_many :client_applications
has_many :tokens, :class_name=>“OauthToken”,:order=>“authorized_at desc”,:include=>[:client_application]

In which file I need to add these lines.

Getting below error when browsing:

NoMethodError in OauthController#login
undefined method `login_required’ for #<OauthController:0×47f552c>

Please help me out

masone December 31st, 2008

I think the link for starting registering client applications should be (instead of /oauth):

To do this I added the corresponding route:
map.resources :oauth_clients

Steven Chau January 4th, 2009

If using restful-authentication plugin, after adding ‘include AuthenticatedSystem’ to the application.rb did the missing errors and variables stopped.

I agree with @masone, http://localhost:3000/oauth_clients presents a working page, rather than using /oauth url. Still trying to figure out that last part.

Kannan R July 9th, 2009

Has anyone tried 2-legged OAuth?

If so can you please let me know if it generates the signatures properly?
i’ve been trying to get the 2-legged OAuth working, but the client and provider generates different signatures.

i tried with other clients as well… still no help yet.

@ clients end

@provider end
Signature is aYqi3i5XI3zEZALugNxo3F6W9Fw=

Sunny August 12th, 2009

Exescue me, I am also new to this, because our web had already finished the login part, but not used plugins above, we wrote the must_login function instead of login_required, but i don’t know how to change oauth_required, can you tell me what should i do, or i just should install the plugin?

Andrea Pigato August 21st, 2009

Hi, I’m trying to figure out if I can, as a consumer, let users authenticate with oauth without the need of local credentials:

my website -> oauth -> twitter -> get user profile

my website -> oauth -> login on twitter = login on my website

Thanks in advance

Michael September 9th, 2009


Great plugin. I jus wanted to know, is it possible to use this with AuthLogic Authentication in Rails ?

Although I have tried using it, I wanted to get rid of the approve app screen and wanted auto approve. Can I make it auto approve ?

Secondly, I tried integrating Authlogic with this plugin, but culdn`t :(


Pelle Braendgaard September 9th, 2009


I want it to be less painful to integrate with authlogic or clearance. As it turns out it’s not too bad.

You need to make sure the following 3 protected methods are implemented in application controller.:

logged_in?, current_user and authorize?

You may already have these, but as authlogic doesn’t have a generator you might not.

  • logged_in? should return true if user is logged in.
  • current_user should return the current user
  • authorize? you can just have return true

If you’re still having problems try sending a message with the errors you are getting to the mailing list and I’m sure we’ll get you sorted out in no time.

Michael September 10th, 2009


Thanks for replying so soon. I would just like to let you know that I have managed to get it up and running with Authlogic :)

I have made my rails site as OAuth Provider and is working fine.

I have a PHP app which will be the consumer. I have managed to get it up and running as well i.e the API requests are working :)

Although, when I logout of my Rails site, I assume, the PHP app should automatically realize this and provide me with a request token once again, instead it still shows me as logged in and gives my access to the Rails site API. Is this a bug ? (I am using the OAuth library for PHP and it is working fine with Twitter, so I am assuming either there is something I am overlooking in my Rails app as OAuth Provider, since the PHP app is flawless)

Thanks Once again :)

Randy September 16th, 2009

Click to Continue Reading… link doesn’t work :( so I can read the whole post. Any help?

Randy September 17th, 2009

Click to Continue Reading works fine now, thanks. I’m seeing @pelle’s email address in the form now, though. Weird.

Randy September 22nd, 2009

The Continue Reading link is broken again :(

Pelle Braendgaard September 22nd, 2009

I don’t even see a Continue Reading link and there shouldn’t be one. What browser are you using?

bmsatierf September 24th, 2009


Is there a way to use the oauth-plugin in a Rails 2.2.2 application with the Engines plugin? I’m getting the following error when trying
to add a new OAuth Client (oauth_clients_controller.rb:16

NameError: uninitialized constant OAuth::Server

Note that this error just occurs in an Rails 2.2.2 application with the Engines plugin (tag 2.2.2).

Here is the setup do reproduce the error above:

Create a Rails 2.2.2 application from scratch:

rails _2.2.2_ provider cd provider

Install the engines plugin with the tag 2.2.2:

script/plugin install --revision 'tag 2.2.2' git://

Add the following line to the top of config/environment.rb. You should add this line just below the require for Rails’ own boot.rb file.

require File.join(File.dirname(__FILE__), '../vendor/plugins/engines/boot')

Install the restful-authentication plugin:

script/plugin install git://

Rename the restful-authentication folder to avoid a NameError exception (lighthouse tracker ticket):

mv vendor/plugins/restful-authentication vendor/plugins/restful_authentication

Run the restful-authentication generator:

script/generate authenticated user sessions

Add the following in the gem dependency section of config/environment.rb:

config.gem "oauth", :version => '0.3.6' config.gem "oauth-plugin", :version => '0.3.10'

Run the rake gem install command:

rake gems:install

Run the oauth generator:

script/generate oauth_provider

Add a few associations to your user object:

has_many :client_applications has_many :tokens, :class_name=>"OauthToken",:order=>"authorized_at desc",:include=>[:client_application]

Run your migrations and open a console:

rake db:migrate script/console

Now print the OAuth::Server:

p OAuth::Server

And you will see the following error:

NameError: uninitialized constant OAuth::Server from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:442:in `load_missing_constant' from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:77:in `const_missing' from (irb):1

Any tip?


Tom September 27th, 2009

i’m also seeing a continue link using firefox 3.5.3 on ubuntu. the post seems to be cut off there with the last text being: “Easy before filter to provide oauth protection on your actions”

i’ll try another browser/OS and see what happens…

Tom September 27th, 2009

this post works fine with firefox 3.5.3 on windows. (not sure why it’s bugging out on ubuntu with 3.5.3)

Paul October 15th, 2009

The article is cut off right after the enumeration of Provider Features. The Continue Reading… link just points to this same page.

Al November 21st, 2009

The article is cut off for me as well (tried several browsers, Mac and Win) and I suspect there is something in it that I need to know. I am having problems getting login_or_oauth_required filter to work. My app is throwing UnknownSignatureMethod exception and I cannot figure out what I’m missing.

Could you provide the full article? Thanks.

dmitry December 29th, 2009

Anybody knows if it’s possible to make oauth work with devise as an authentication solution. I have to use since at this time this is the only authentication solution that works with mongo mapper. Any help would be greatly appreciated.

Aditya Sanghi January 18th, 2010

Hi Pelle,

The document gets cut off and there is a continue reading link below. Using FF 3.5.7 on Windows. Please help!


suprie March 24th, 2010

hi, i just tried to use this plugin… and it works like a charm.

Just wondered, when i’m adding new clients, what does “Callback URL” mean ?


Shak June 21st, 2010

>You need to make sure the following 3 protected methods are implemented in application controller.:

>logged_in?, current_user and authorize?

Should that be “authorized?”? If not, I get a authorized? method not found error, called by login_or_oauth_required.

If you did want that to return true, then OAuth doesn’t work (it allows all users).

Dennis September 14th, 2010

I just installed the 2 oauth gems and when I ran the rails generate oauth_provider I received this error: Could not find generator oauth_provider. I am using Rails 3 with Ruby 1.9. Can this be done using Rails 3?

Dennis September 14th, 2010

Nevermind! I figured it out using the reply in your google forum. Thanks!

Saurabh Purnaye January 17th, 2011

Hi Pelle,
Thanks a ton for blog about oauth-plugin
I am using oauth and oauth-plugin with rails 3, authentication system used is devise.
here is my gemfile.

gem ‘devise’, :git => “”
gem ‘oauth’, :git => “”
gem ‘oauth-plugin’, :git => “”, :branch => “rails3”

I have added following code in my application controller.

require ‘oauth/request_proxy/rack_request’
require ‘oauth/controllers/application_controller_methods’
class ApplicationController < ActionController::Base
include OAuth::Controllers::ApplicationControllerMethods
alias :logged_in? :user_signed_in?
alias :login_required :authenticate_user!

I am able to access GET and DELETE methods thr API but the POST and PUT is giving 401 error.
Could you please suggest any changes?


Sandro Padin January 21st, 2011

Hi Pelle,

Maybe I’m a little too new to Rails, and I’m not sure what’s going on, but are the generators supposed to generate views when using:

rails g oauth_provider ?

I’m using rails 3, I also pointed bundler to load the gem from your rails3 branch on github.

I see the views in your source, but they appear to get generated for me.

I have this on my application.rb as well

config.generators do |g|
g.orm :active_record
g.template_engine :erb

Alex Savin March 1st, 2011

>>Maybe I’m a little too new to Rails, and I’m not sure what’s going on, but are the generators supposed to generate views?

I have the same question. Tried this with Rails 3, no views are generated. Got generated following models + migration file:

identical app/models/client_application.rb identical app/models/oauth_token.rb identical app/models/request_token.rb identical app/models/access_token.rb identical app/models/oauth2_token.rb identical app/models/oauth2_verifier.rb identical app/models/oauth_nonce.rb

No views. How do I get them?

pjammer April 30th, 2011

for those that need it:

rails g oauth_provider oauth

that will create the views and stuff. You need a NAME after the command. I chose oauth, i guess it could be anything that made sense.

MrPlazmaDude July 26th, 2011

You have saved me many days of work and are now my hero!

Alex September 16th, 2011

Hi Pelle -

Does the oauth-plugin work with Devise as its authentication system? I have to use Devise to work with MongoDB.

I’m also getting this error when trying to load the OAuth Rack filter: no such file to load — oauth/rack/oauth_filter (LoadError)

I have the gems and plugin installed and oauth_provider generated.



christoffer September 24th, 2011


I followed your instructions and everything seem to be working out so far. However, I am now creating a second app in which I want to authorize with OAuth.

But I have no clue how this should be done. If I go to the /oauth/authorize url I get the login but how do I access the consumer name? What extra parameters should be sent with the GET request?


About me

Pelle gravatar 160

My name is Pelle Braendgaard. Pronounce it like Pelé the footballer (no relation). CEO of Notabene where we are building FATF Crypto Travel Rule compliance software.

Most new articles by me are posted on our blog about Crypto markets, regulation and compliance

More about me:

Current projects and startups:

Other under Programming

Popular articles