support nil ip

lib/travis/api/attack.rb

@@ -38,7 +38,7 @@ class Rack::Attack
 
   # https://help.github.com/articles/what-ip-addresses-does-github-use-that-i-should-whitelist/
   whitelist('safelist anything coming from github') do |request|
-    NetAddr::CIDR.create('192.30.252.0/22').contains?(request.ip)
+    request.ip && NetAddr::CIDR.create('192.30.252.0/22').contains?(request.ip)
   end
 
   ####

spec/unit/attack_spec.rb

@@ -13,7 +13,7 @@ describe Rack::Attack do
   describe 'request from GitHub ip' do
     let(:request) {
       env = Rack::MockRequest.env_for("https://api-test.travis-ci.org/repos/rails/rails/branches", {
-        'REMOTE_ADDR' => '192.30.252.42'
+        'REMOTE_ADDR' => '192.30.252.42',
       })
       Rack::Attack::Request.new(env)
     }