GRN2-6: Added the ability for admins to specify registration method (#520)

* Added the ability to invite users

* Small bug fix

* Added the ability to approve/decline users

* Small bug fixes

* More bug fixes

* More minor changes

* Final changes

app/controllers/sessions_controller.rb

@@ -17,6 +17,8 @@
 # with BigBlueButton; if not, see <http://www.gnu.org/licenses/>.
 
 class SessionsController < ApplicationController
+  include Registrar
+
   skip_before_action :verify_authenticity_token, only: [:omniauth, :fail]
 
   # GET /users/logout
@@ -32,11 +34,11 @@ class SessionsController < ApplicationController
       user = admin
     else
       user = User.find_by(email: session_params[:email], provider: @user_domain)
-      redirect_to(root_path, alert: I18n.t("invalid_user")) && return unless user
+      redirect_to(signin_path, alert: I18n.t("invalid_user")) && return unless user
       redirect_to(root_path, alert: I18n.t("invalid_login_method")) && return unless user.greenlight_account?
       redirect_to(account_activation_path(email: user.email)) && return unless user.activated?
     end
-    redirect_to(root_path, alert: I18n.t("invalid_credentials")) && return unless user.try(:authenticate,
+    redirect_to(signin_path, alert: I18n.t("invalid_credentials")) && return unless user.try(:authenticate,
       session_params[:password])
 
     login(user)
@@ -44,11 +46,26 @@ class SessionsController < ApplicationController
 
   # GET/POST /auth/:provider/callback
   def omniauth
-    user = User.from_omniauth(request.env['omniauth.auth'])
-    login(user)
-  rescue => e
-    logger.error "Error authenticating via omniauth: #{e}"
-    omniauth_fail
+    begin
+      @auth = request.env['omniauth.auth']
+      @user_exists = check_user_exists
+
+      # If using invitation registration method, make sure user is invited
+      return redirect_to root_path, flash: { alert: I18n.t("registration.invite.no_invite") } unless passes_invite_reqs
+
+      user = User.from_omniauth(@auth)
+
+      # Add pending role if approval method and is a new user
+      if approval_registration && !@user_exists
+        user.add_role :pending
+        return redirect_to root_path, flash: { success: I18n.t("registration.approval.signup") }
+      end
+
+      login(user)
+    rescue => e
+        logger.error "Error authenticating via omniauth: #{e}"
+        omniauth_fail
+    end
   end
 
   # POST /auth/failure
@@ -61,4 +78,17 @@ class SessionsController < ApplicationController
   def session_params
     params.require(:session).permit(:email, :password)
   end
+
+  def check_user_exists
+    provider = @auth['provider'] == "bn_launcher" ? @auth['info']['customer'] : @auth['provider']
+    User.exists?(social_uid: @auth['uid'], provider: provider)
+  end
+
+  # Check if the user already exists, if not then check for invitation
+  def passes_invite_reqs
+    return true if @user_exists
+
+    invitation = check_user_invited("", session[:invite_token], @user_domain)
+    invitation[:present]
+  end
 end