Generating suggested whitelists for Naxsi Web Application Firewall from multiple error logs. This assumes you want a distinct set for each log.

naxsi-rules

#!/usr/bin/env ruby

require 'fileutils'

nx_dir = 'naxsi-rules.d'
rules_dir = 'etc/nginx/naxsi'

FileUtils.mkdir_p nx_dir

Dir['var/log/nginx/*.error.log'].each do |log_path|
  log_name = File.basename(log_path, '.error.log')
  db_path = File.join nx_dir, "#{log_name}.naxsi.sqlite"
  rules_path = File.join rules_dir, "#{log_name}-generated.rules"
  `nx_util.py -l #{log_path}* -d #{db_path}`
  `nx_util.py -o -d #{db_path} -c nx_util.conf > #{rules_path}`
end

nx_util.conf

[nx_util]
data_dir=/usr/local/nx_datas
database_dir=
naxsi_core_rules=etc/nginx/naxsi_core.rules