custom OpsWorks cookbook memcached.yml.erb that supports memcached cluster

memcached.yml.erb

# rails/templates/default/memcached.yml.erb

<%
instances = node[:opsworks][:layers][:memcached][:instances]
instances = {:localhost => {:private_ip => "127.0.0.1"}} if instances.empty?
-%>
hosts:
<% instances.each_pair do |name, cache_server| -%>
  - "<%= cache_server[:private_ip]%>:<%= @memcached[:port] %>"
<% end -%>

production.rb

# config/environments/production.rb

MyProject::Application.configure do

  # ...
  
  memcached_config = YAML.load_file(Rails.root + 'config/memcached.yml')
  memcached_hosts = memcached_config['hosts']
  config.cache_store = :dalli_store, *memcached_hosts,
      {
        namespace: 'myproject',
        expires_in: 1.day,
        compress: true,
      }

  # ...

end