ips_from

# File actionpack/lib/action_dispatch/middleware/remote_ip.rb, line 173
      def ips_from(header)
        # Split the comma-separated list into an array of strings
        ips = @env[header] ? @env[header].strip.split(/[,\s]+/) : []
        # Only return IPs that are valid according to the regex
        ips.select{ |ip| ip =~ VALID_IP }
      end