app/views/home/opensearch.xml.erb
<?xml version="1.0"?>
<OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/">
<ShortName><%= t 'app.title' %></ShortName>
<Description><%= t 'app.description' %></Description>
<Url type="text/html" method="get" template="<%= request.protocol %><%= request.host_with_port %>/search/all?query={searchTerms}"/>
</OpenSearchDescription>