add sidekiq worker, update endpoint

Procfile

@@ -1,2 +1,3 @@
 web: bundle exec ./script/server
 console: bundle exec ./script/console
+sidekiq: bundle exec sidekiq -c 5 -r ./lib/travis/sidekiq.rb -q build_cancellations

lib/travis/api/app/endpoint/builds.rb

@@ -37,7 +37,9 @@ class Travis::Api::App
           status 422
           respond_with json
         else
-          service.run
+          #service.run
+          #check syntax of line below
+          Travis::Sidekiq::BuildCancellation.perform_async(params.merge(source: 'api'))
 
           Metriks.meter("api.request.cancel_build.success").mark
           status 204

lib/travis/api/workers/build_cancellation.rb

@@ -0,0 +1,29 @@
+require 'sidekiq/worker'
+require 'multi_json'
+
+module Travis
+  module Sidekiq
+    class BuildCancellation
+      class ProcessingError < StandardError; end
+
+      include ::Sidekiq::Worker
+      # do we need to name the queue here? we didn't do this in Admin. We passed this info in the procfile
+      sidekiq_options queue: build_cancellations
+
+      attr_accessor :data
+
+      def perform(data)
+        @data = data
+        if payload
+          service.run
+        else
+          Travis.logger.warn("The #{type} payload was empty and could not be processed")
+        end
+      end
+
+      def service
+        @service ||= Travis.service(:cancel_build, data)
+      end
+    end
+  end
+end

lib/travis/sidekiq.rb

@@ -0,0 +1,7 @@
+$: << './lib'
+require 'travis/core'
+require 'travis/app/workers/build_cancellation'
+
+Sidekiq.configure_server do |config|
+  config.redis = Travis.config.redis.merge(namespace: Travis.config.sidekiq.namespace)
+end