Ensure cookies from incoming request are passed to Grover via Middleware

lib/grover/middleware.rb

@@ -97,9 +97,15 @@ def convert_to_pdf(grover)
     def create_grover_for_response(response)
       body = response.respond_to?(:body) ? response.body : response.join
       body = body.join if body.is_a?(Array)
-
       body = HTMLPreprocessor.process body, root_url, protocol
-      Grover.new(body, display_url: request_url)
+
+      options = { display_url: request_url }
+      cookies = Rack::Utils.parse_cookies(env).map do |name, value|
+        { name: name, value: value, domain: env['HTTP_HOST'] }
+      end
+      options[:cookies] = cookies if cookies.any?
+
+      Grover.new(body, options)
     end
 
     def add_cover_content(grover)

spec/grover/middleware_spec.rb

@@ -377,6 +377,20 @@ def request_env
         expect(last_response.body).to eq 'A converted PDF'
       end
 
+      it 'passes through cookies to Grover' do
+        expect(Grover).to(
+          receive(:new).
+            with(
+              'Grover McGroveryface',
+              display_url: 'http://www.example.org/test',
+              cookies: [{ domain: 'www.example.org', name: 'key', value: 'value' }]
+            ).and_return(grover)
+        )
+        expect(grover).to receive(:to_pdf).with(no_args).and_return 'A converted PDF'
+        get 'http://www.example.org/test.pdf', nil, { 'HTTP_COOKIE' => 'key=value' }
+        expect(last_response.body).to eq 'A converted PDF'
+      end
+
       context 'when app configuration has PDF middleware disabled' do
         before { allow(Grover.configuration).to receive(:use_pdf_middleware).and_return false }