title: Write a custom OmniAuth strategy
body: <p>I've got a Rail 4 app with Devise.
  I'm trying to configure OmniAuth to use our corporate Ping OpenID Connect IdP.
  It appears that I have to write an OmniAuth strategy in Rack Middleware.</p>
  
  <p>I took the 'omniauth-digitalocean' gem (which has their strategy) and carefully replaced all references of 'digitalocean' with another name. I was careful to respect all case to conform to convention.</p>
  
  <p>The problem I'm having now is that I appear to have a private gem.
  I added it to my Gemfile with:</p>
  
  <pre><code>gem 'omniauth-private', :path =&gt; "/var/lib/gems/2.0.0/gems/omniauth-private-0.1.0"
  </code></pre>
  
  <p>I get no errors when I run 'bundle install'.</p>
  
  <p>I was getting this error with 'rake db:migrate':</p>
  
  <pre><code>fatal: Not a git repository (or any of the parent directories): .git
  </code></pre>
  
  <p>I believe this was caused by a .gitignore file in my custom gem.
  I deleted the .gitignore file and now I'm getting:</p>
  
  <pre><code>Devise::OmniAuth::StrategyNotFound: Could not find a strategy with name `Private'. Please ensure it is required or explicitly set it using the :strategy_class option.
  </code></pre>
  
  <p>This is the same error message I was getting before I figure out I needed to write n Omniuth strategy, so I think it means my gem is not being recognized.</p>
  
  <p>So I'm not sure exactly what's going on. I think I'm struggling with this private gem. But it could be an OmniAuth problem too.</p>
  
  <p>Anyone ever gotten a private OpenID Connect IdP working with OmniAuth?</p>