Add registration_limit to conference model. Added the input for registration limit in the edit conference form. In the controller, if the limit has exceeded redirect to root_path with an alert. fix #761

app/controllers/admin/conference_controller.rb

@@ -211,7 +211,7 @@ module Admin
                                          :vpositions_attributes, :use_volunteers, :color,
                                          :sponsorship_levels_attributes, :sponsors_attributes,
                                          :photos_attributes, :targets, :targets_attributes,
-                                         :campaigns, :campaigns_attributes)
+                                         :campaigns, :campaigns_attributes, :registration_limit)
     end
 
     def get_users(role_name)

app/controllers/conference_registrations_controller.rb

@@ -20,6 +20,11 @@ class ConferenceRegistrationsController < ApplicationController
       redirect_to edit_conference_conference_registrations_path(@conference.short_title)
     end
 
+    if @conference.registration_limit_exceeded?
+      redirect_to root_path, alert: "Sorry, registration limit exceeded for #{@conference.title}"
+      return
+    end
+
     @registration = Registration.new
 
     # @user variable needs to be set so that _sign_up_form_embedded works properly

app/models/conference.rb

@@ -65,6 +65,7 @@ class Conference < ActiveRecord::Base
 
   validates_uniqueness_of :short_title
   validates_format_of :short_title, with: /\A[a-zA-Z0-9_-]*\z/
+  validates :registration_limit, numericality: { only_integer: true, greater_than_or_equal_to: 0 }
 
   # This validation is needed since a conference with a start date greater than the end date is not possible
   validate :valid_date_range?
@@ -536,6 +537,10 @@ class Conference < ActiveRecord::Base
     email_settings.conference_registration_dates_updated_body
   end
 
+  def registration_limit_exceeded?
+    registration_limit > 0 && registrations.count >= registration_limit
+  end
+
   private
 
   after_create do

app/models/registration.rb

@@ -26,6 +26,7 @@ class Registration < ActiveRecord::Base
   validates :user, presence: true
 
   validates_uniqueness_of :user_id, scope: :conference_id, message: 'already Registered!'
+  validate :registration_limit_not_exceed, on: :create
 
   after_create :set_week, :subscribe_to_conference, :send_registration_mail
 
@@ -49,4 +50,10 @@ class Registration < ActiveRecord::Base
     self.week = created_at.strftime('%W')
     save!
   end
+
+  def registration_limit_not_exceed
+    if self.conference.registration_limit>0 && self.conference.registrations(:reload).count >= self.conference.registration_limit
+      errors.add(:base, 'Registration limit exceeded')
+    end
+  end
 end

app/views/admin/conference/edit.html.haml

@@ -18,5 +18,6 @@
         = f.input :timezone, :as => :time_zone, :hint => "The conference time zone"
         = f.input :start_date, :as => :string, :input_html => { :id => "conference-start-datepicker", :readonly => "readonly"  }
         = f.input :end_date, :as => :string, :input_html => { :id => "conference-end-datepicker", :readonly => "readonly"  }
+      = f.inputs name: "Registrations" do
+        = f.input :registration_limit, as: :number, in: 0..9999, hint: "Limit the number of registrations to the conference (0 no limit)"
       = f.action :submit, :as => :button, :button_html => {:class => "btn btn-primary"}
-

app/views/conference/_conference_details.html.haml

@@ -27,7 +27,9 @@
               - if conference.user_registered?(current_user)
                 = link_to "My Registration", conference_conference_registrations_path(conference.short_title), :class =>"btn btn-default"
               - else
-                = link_to "Register", new_conference_conference_registrations_path(conference.short_title), :class =>"btn btn-default"
+                = link_to "Register", new_conference_conference_registrations_path(conference.short_title), class: "btn btn-default", disabled: conference.registration_limit_exceeded?
+                - if conference.registration_limit_exceeded?
+                  Sorry, no places left
             - if !current_user.nil? && current_user.proposal_count(conference) > 0
               = link_to "My Proposals", conference_program_proposal_index_path(conference.short_title), :class =>"btn btn-default"
             - elsif conference.program.cfp_open?

app/views/conference/_registration.html.haml

@@ -6,19 +6,25 @@
   .row
     .col-md-12.text-center
       %h1 Registration
-      - if @conference.tickets.empty?
-        %p.lead
-          Going to
-          = @conference.short_title
-          is free of charge.
+
+      - if @conference.registration_limit_exceeded?
         %p
-          We only ask you to register yourself until
-          = @conference.registration_period.end_date.strftime('%A, %B %-d. %Y')
-          so we can plan for the right amount of people.
+          Sorry, the conference registration limit has exceeded
       - else
-        %p
-          The registration period ends on
-          = @conference.registration_period.end_date.strftime('%A, %B %-d. %Y')
-      %p.cta-button
+        - if @conference.tickets.empty?
+          %p.lead
+            Going to
+            = @conference.short_title
+            is free of charge.
+          %p
+            We only ask you to register yourself until
+            = @conference.registration_period.end_date.strftime('%A, %B %-d. %Y')
+            so we can plan for the right amount of people.
+            %p.cta-button
+        - else
+          %p
+            The registration period ends on
+            = @conference.registration_period.end_date.strftime('%A, %B %-d. %Y')
+          %p.cta-button
         = link_to(new_conference_conference_registrations_path(@conference.short_title), class: 'btn btn-lg btn-success') do
           Register Now