Merge pull request #283 from concord-consortium/auto-login-teachers-f…

…or-preview

Added auto login for teachers when previewing an activity

app/controllers/external_activities_controller.rb

@@ -74,7 +74,19 @@ def show
       format.html {
         redirect_to(browse_external_activity_path(@external_activity))
       }
-      format.run_resource_html   { redirect_to(@external_activity.url) }
+      format.run_resource_html {
+        # ensure that a logged in user is the same user on LARA
+        if !current_visitor.anonymous?
+           uri = URI.parse(@external_activity.url)
+           query = Rack::Utils.parse_query(uri.query)
+           query["domain"] = root_url
+           query["domain_uid"] = current_visitor.id
+           uri.query = Rack::Utils.build_query(query)
+           redirect_to(uri.to_s)
+        else
+          redirect_to(@external_activity.url)
+        end
+      }
       format.xml  { render xml: @external_activity }
       format.json { render json: @external_activity }
     end