Subscription on Registration, Independent Subscription without registration

app/controllers/conference_controller.rb

@@ -4,6 +4,42 @@ class ConferenceController < ApplicationController
     redirect_to root_path, notice: "Conference not ready yet!!" unless @conference.make_conference_public?
   end
 
+  def subscribe
+    conference = Conference.find_by_short_title(params[:id])
+    if current_user.subscriptions.where(conference: conference).blank?
+      subscription = Subscription.new(user_id: current_user.id, conference_id: conference.id)
+      begin
+        subscription.save!
+        flash[:success] = "You have been subscribed to receive Email Notifications from this Conference."
+        redirect_to root_path
+      rescue ActiveRecord::RecordInvalid
+        flash[:error] = subscription.errors.full_messages.to_sentence
+        redirect_to root_path
+      end
+    else
+      flash[:notice] = "Already Subscribed"
+      redirect_to root_path
+    end
+  end
+
+  def unsubscribe
+    conference = Conference.find_by_short_title(params[:id])
+    subscription = current_user.subscriptions.where(conference_id: conference.id).first
+    if subscription.blank?
+      flash[:notice] = "Already Unsubscribed"
+      redirect_to root_path
+    else
+     begin
+        subscription.destroy!
+        flash[:notice] = "You have been unsubscribed and now you won't be receiving any Email Notifications."
+        redirect_to root_path
+      rescue ActiveRecord::RecordInvalid
+        flash[:error] = subscription.errors.full_messages.to_sentence
+        redirect_to root_path
+      end
+    end
+  end
+
   def gallery_photos
     @photos = Conference.find_by_short_title(params[:id]).photos
     render "photos", formats: [:js]