Question

I’m trying to get Facebook logins working on my app using Rails, Authlogic, and Omniauth. I’m following the first steps of http://railscasts.com/episodes/235-omniauth-part-1 as precisely as possible.

I have:

• added the omniauth gem, run bundle install.
• created a new Authentication nifty-scaffold with fields user_id, provider, and uid.
• added the route: match '/auth/:provider/callback' => 'authentications#create'

• added to config/initializers/omniauth.rb:

  Rails.application.config.middleware.use OmniAuth::Builder do
    provider :facebook, '20...my_app_id', 'bc...my_app_secret'
  end
  

The server then fails to restart:

/Users/san/.rvm/gems/ruby-1.9.2-p0/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:206:
    in 'const_missing_from_s3_library': uninitialized constant 
    OmniAuth::Strategies::Facebook (NameError)
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/ext/module.rb:36:in 'const_missing'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/omniauth-1.0.0/lib/omniauth/builder.rb:22:in 'const_get'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/omniauth-1.0.0/lib/omniauth/builder.rb:22:in 'provider'
    from /Users/san/Documents/sanj/myapp/config/initializers/omniauth.rb:2:in 'block in <top (required)>'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/builder.rb:46:in 'instance_eval'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/builder.rb:46:in 'initialize'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/omniauth-1.0.0/lib/omniauth/builder.rb:7:in 'initialize'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/actionpack-3.0.10/lib/action_dispatch/middleware/stack.rb:33:in 'new'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/actionpack-3.0.10/lib/action_dispatch/middleware/stack.rb:33:in 'build'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/actionpack-3.0.10/lib/action_dispatch/middleware/stack.rb:79:in 'block in build'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/actionpack-3.0.10/lib/action_dispatch/middleware/stack.rb:79:in 'each'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/actionpack-3.0.10/lib/action_dispatch/middleware/stack.rb:79:in 'inject'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/actionpack-3.0.10/lib/action_dispatch/middleware/stack.rb:79:in 'build'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/application.rb:162:in 'app'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/application/finisher.rb:35:in 'block in <module:Finisher>'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/initializable.rb:25:in 'instance_exec'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/initializable.rb:25:in 'run'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/initializable.rb:50:in 'block in run_initializers'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/initializable.rb:49:in 'each'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/initializable.rb:49:in 'run_initializers'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/application.rb:134:in 'initialize!'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/application.rb:77:in 'method_missing'
    from /Users/san/Documents/sanj/myapp/config/environment.rb:5:in '<top (required)>'
    from /Users/san/Documents/sanj/myapp/config.ru:3:in 'block in <main>'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/builder.rb:46:in 'instance_eval'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/builder.rb:46:in 'initialize'
    from /Users/san/Documents/sanj/myapp/config.ru:1:in 'new'
    from /Users/san/Documents/sanj/myapp/config.ru:1:in '<main>'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/builder.rb:35:in 'eval'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/builder.rb:35:in 'parse_file'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/server.rb:162:in 'app'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/server.rb:253:in 'wrapped_app'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/rack-1.2.3/lib/rack/server.rb:204:in 'start'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/commands/server.rb:65:in 'start'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/commands.rb:30:in 'block in <top (required)>'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/commands.rb:27:in 'tap'
    from /Users/san/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.10/lib/rails/commands.rb:27:in '<top (required)>'
    from script/rails:7:in 'require'
    from script/rails:7:in '<main>'

Answer 1

The omniauth gem was just bumped to version 1.0 as of yesterday (http://intridea.com/2011/11/2/omniauth-1-0), and there are some changes to how the gem is used that are not covered in the railscast.

I found my solution on this page: https://github.com/intridea/omniauth/wiki/OmniAuth-1.0

The biggest different is that each strategy is now contained within its own gem, so for facebook, you would change the line in your gem file that currently reads “gem ‘omniauth'” to “gem ‘omniauth-facebook'”.

I didn’t have to change any other code, and you may have to run “bundle update” to get everything to click through.