add lb option

app/controllers/application_controller.rb

@@ -20,10 +20,21 @@ class ApplicationController < ActionController::Base
 
   # Determines if the BigBlueButton endpoint is configured (or set to default).
   def bigbluebutton_endpoint_default?
+    return false if loadbalanced_configuration?
     Rails.configuration.bigbluebutton_endpoint_default == Rails.configuration.bigbluebutton_endpoint
   end
   helper_method :bigbluebutton_endpoint_default?
 
+  def loadbalanced_configuration?
+    Rails.configuration.loadbalanced_configuration
+  end
+  helper_method :loadbalanced_configuration?
+
+  def allow_greenlight_users?
+    Rails.configuration.greenlight_accounts
+  end
+  helper_method :allow_greenlight_users?
+
   private
 
   # Ensure the user is logged into the room they are accessing.

app/controllers/sessions_controller.rb

@@ -6,8 +6,8 @@ class SessionsController < ApplicationController
 
   # GET /logout
   def destroy
-    logout if current_user
-    head :no_content
+    logout
+    redirect_to root_path
   end
 
   # POST /login
@@ -22,6 +22,18 @@ class SessionsController < ApplicationController
     end
   end
 
+  # POST /launch
+  def launch
+    # This will recieve a encoded POST from a launcher that
+    # contains the provider, and all user information. The
+    # launcher is what does the authentication, so we know
+    # that the user is who they say they are. We just need
+    # to use our secret to decode it and then log them in
+    # to GreenLight (or sign them up).
+
+    # User.from_launch()
+  end
+
   # GET/POST /auth/:provider/callback
   def omniauth
     user = User.from_omniauth(request.env['omniauth.auth'])

app/helpers/sessions_helper.rb

@@ -8,7 +8,6 @@ module SessionsHelper
   # Logs current user out of GreenLight.
   def logout
     session.delete(:user_id) if current_user
-    redirect_to root_path
   end
 
   # Retrieves the current user.

app/models/meeting.rb

@@ -6,6 +6,8 @@ class Meeting < ApplicationRecord
 
   belongs_to :room
 
+  RETURNCODE_SUCCESS = "SUCCESS"
+
   # Creates a meeting on the BigBlueButton server.
   def create(options = {})
     create_options = {
@@ -86,9 +88,59 @@ class Meeting < ApplicationRecord
     Rails.configuration.bigbluebutton_secret
   end
 
-  # Use one common instance of the BigBlueButton API for all meetings.
+  # Sets a BigBlueButtonApi object for interacting with the API.
   def bbb
-    @@bbb ||= BigBlueButton::BigBlueButtonApi.new(bbb_endpoint + "api", bbb_secret, "0.8")
+    @bbb ||= if Rails.configuration.loadbalanced_configuration
+      lb_user = retrieve_loadbalanced_credentials(self.room.user.provider)
+      BigBlueButton::BigBlueButtonApi.new(remove_slash(lb_user["apiURL"]), lb_user["secret"], "0.8")
+    else
+      BigBlueButton::BigBlueButtonApi.new(remove_slash(bbb_endpoint), bbb_secret, "0.8")
+    end
+  end
+
+  # Rereives the loadbalanced BigBlueButton credentials for a user.
+  def retrieve_loadbalanced_credentials(provider)
+    # Include Omniauth accounts under the Greenlight provider.
+    provider = "greenlight" if Rails.configuration.providers.include?(provider.to_sym)
+
+    # Build the URI.
+    uri = encode_bbb_url(
+      Rails.configuration.loadbalancer_endpoint,
+      Rails.configuration.loadbalancer_secret,
+      {name: provider}
+    )
+
+    # Make the request.
+    http = Net::HTTP.new(uri.host, uri.port)
+    http.use_ssl = (uri.scheme == 'https')
+    response = http.get(uri.request_uri)
+
+    unless response.kind_of?(Net::HTTPSuccess)
+      raise "Error retrieving provider credentials: #{response.code} #{response.message}"
+    end
+
+    # Parse XML.
+    doc = XmlSimple.xml_in(response.body, 'ForceArray' => false)
+
+    # Return the user credentials if the request succeeded on the loadbalancer.
+    return doc['user'] if doc['returncode'] == RETURNCODE_SUCCESS
+
+    raise "User with provider #{provider} does not exist." if doc['messageKey'] == "noSuchUser"
+    raise "API call #{url} failed with #{doc['messageKey']}."
+  end
+
+  # Builds a request to retrieve credentials from the load balancer.
+  def encode_bbb_url(base_url, secret, params)
+    encoded_params = OAuth::Helper.normalize(params)
+    string = "getUser" + encoded_params + secret
+    checksum = OpenSSL::Digest.digest('sha1', string).unpack("H*").first
+
+    URI.parse("#{base_url}?#{encoded_params}&checksum=#{checksum}")
+  end
+
+  # Removes trailing forward slash from BigBlueButton URL.
+  def remove_slash(s)
+    s.nil? ? nil : s.chomp("/")
   end
 
   # Generates a BigBlueButton meeting id from a meeting token.

app/models/user.rb

@@ -1,14 +1,14 @@
 class User < ApplicationRecord
 
   after_create :initialize_room
-  before_save { email.downcase! }
+  before_save { email.downcase! unless email.nil? }
 
   has_one :room
 
   validates :name, length: { maximum: 24 }, presence: true
   validates :username, presence: true
   validates :provider, presence: true
-  validates :email, length: { maximum: 60 }, presence: true,
+  validates :email, length: { maximum: 60 }, allow_nil: true,
                     uniqueness: { case_sensitive: false },
                     format: {with: /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i }
 
@@ -31,6 +31,11 @@ class User < ApplicationRecord
       user
     end
 
+    # Generates a user from a trusted launcher.
+    def from_launch(auth)
+
+    end
+
     private
 
     # Provider attributes.
@@ -57,7 +62,6 @@ class User < ApplicationRecord
     def google_email(auth)
       auth['info']['email']
     end
-
   end
 
   private

app/views/sessions/new.html.erb

@@ -24,20 +24,22 @@
             <% end %>
           <% end %>
 
-          <center><p>or...<br><br></p></center>
+          <% if allow_greenlight_users? %>
+            <center><p>or...<br><br></p></center>
 
-          <%= form_for(:session, url: login_path) do |f| %>
-            <div class="input-field col s12">
-              <%= f.label :email, "Email Address" %>
-              <%= f.text_field :email %>
-            </div>
-            <div class="input-field col s12">
-              <%= f.label :password %>
-              <%= f.password_field :password %>
-            </div>
-            <br>
-            <%= f.submit "Login", class: "btn white-text light-green" %>
-            <%= link_to "Don't have an account? Sign up!", signup_path %>
+            <%= form_for(:session, url: login_path) do |f| %>
+              <div class="input-field col s12">
+                <%= f.label :email, "Email Address" %>
+                <%= f.text_field :email %>
+              </div>
+              <div class="input-field col s12">
+                <%= f.label :password %>
+                <%= f.password_field :password %>
+              </div>
+              <br>
+              <%= f.submit "Login", class: "btn white-text light-green" %>
+              <%= link_to "Don't have an account? Sign up!", signup_path %>
+            <% end %>
           <% end %>
         </div>
       <% end %>