Rails 3 Controller for Chargify Webhooks

hooks_controller.rb

require 'digest/md5'

class Chargify::HooksController < ApplicationController
	protect_from_forgery :except => :dispatch_handler
	before_filter :verify, :only => :dispatch_handler

	EVENTS = %w[ test signup_success signup_failure renewal_success renewal_failure payment_success payment_failure billing_date_change subscription_state_change subscription_product_change ].freeze

	def dispatch_handler
		event = params[:event]

		unless EVENTS.include? event
		  render :nothing => true, :status => 404 and return
		end

		begin
			convert_payload
			self.send event
		rescue Exception => e
			notify_hoptoad(e) #If you use hoptoad...
		  render :nothing => true, :status => 422 and return
		end
	end

	def test
		Rails.logger.debug "Chargify Webhook test!"
		  render :nothing => true, :status => 200
	end

	def signup_success
		  render :nothing => true, :status => 200
	end

	def signup_failure
		  render :nothing => true, :status => 200
	end

	def renewal_success
		  render :nothing => true, :status => 200
	end

	def renewal_failure
		  render :nothing => true, :status => 200
	end

	def payment_success
		  render :nothing => true, :status => 200
	end

	def payment_failure
		  render :nothing => true, :status => 200
	end

	def billing_date_change
		  render :nothing => true, :status => 200
	end

	def subscription_state_change
		  render :nothing => true, :status => 200
	end

	def subscription_product_change
		  render :nothing => true, :status => 200
	end

	protected
	def verify
		if params[:signature].nil?
			params[:signature] = request.headers["HTTP_X_CHARGIFY_WEBHOOK_SIGNATURE"]
		end


		unless Digest::MD5::hexdigest(ENV['CHARGIFY_SUBDOMAIN_SHARED_KEY'] + request.raw_post) == params[:signature]
		  render :nothing => true, :status => :forbidden
		end
	end

	def convert_payload
		if params[:payload].has_key? :transaction
			@transaction = Chargify::Transaction.new params[:payload][:transaction]
		end

		if params[:payload].has_key? :subscription
			@subscription = Chargify::Subscription.new params[:payload][:subscription]
		end
	end
end

# to put in the routes.rb file...
#  namespace 'chargify' do
#    match '/hooks' => "hooks#dispatch_handler", :via => "post"
#  end

Also I had to change "MD5::hexdigest" to "Digest::MD5.hexdigest"