add put_object_acl request to Google Cloud Storage service

lib/fog/google/requests/storage/put_object_acl.rb

@@ -0,0 +1,55 @@
+module Fog
+  module Storage
+    class Google
+      class Real
+
+        # TODO: move this methods to helper to use them with put_bucket_acl request
+        def tag(name, value)
+          "<#{name}>#{value}</#{name}>"
+        end
+
+        def scope_tag(scope)
+          if %w(AllUsers AllAuthenticatedUsers).include?(scope['type'])
+            "<Scope type='#{scope['type']}'/>"
+          else
+            "<Scope type='#{scope['type']}'>" + 
+              scope.to_a.select {|pair| pair[0] != 'type'}.map { |pair| tag(pair[0], pair[1]) }.join("\n") +
+            "</Scope>"
+          end
+        end
+
+        def entries_list(access_control_list)
+          access_control_list.map do |entry|
+            tag('Entry', scope_tag(entry['Scope']) + tag('Permission', entry['Permission']))
+          end.join("\n")
+        end
+
+        def put_object_acl(bucket_name, object_name, acl)
+
+          data = <<-DATA
+<AccessControlList>
+  <Owner>
+    #{tag('ID', acl['Owner']['ID'])}
+  </Owner>
+  <Entries>
+    #{entries_list(acl['AccessControlList'])}
+  </Entries>
+</AccessControlList>
+DATA
+
+          request({
+            :body     => data,
+            :expects  => 200,
+            :headers  => {},
+            :host     => "#{bucket_name}.#{@host}",
+            :method   => 'PUT',
+            :query    => {'acl' => nil},
+            :path     => CGI.escape(object_name)
+          })
+
+        end
+
+      end
+    end
+  end
+end

lib/fog/google/storage.rb

@@ -31,6 +31,7 @@ module Fog
       request :put_bucket
       request :put_bucket_acl
       request :put_object
+      request :put_object_acl
       request :put_object_url
 
       module Utils