anchor.diff:  
   [nginx_error-default]
   type = "LogstreamerInput"
  +parser_type = "token"
   log_directory = "/var/log/nginx"
   file_match = 'error\.log\.?(?P<Index>\d+)?(\.gz)?'
   differentiator = ["default", "-error"]
  
positive.code: 
  [nginx_access-vhosts]
  type = "LogstreamerInput"
  log_directory = "/var/log/nginx"
  file_match = '(?P<LogBasename>.+)-json\.event\.access\.log\.?(?P<Index>\d+)?(\.gz)?'
  differentiator = ["LogBasename"]
  
negative.code: [nginx_access-default]
  type = "LogstreamerInput"
  parser_type = "token"
  log_directory = "/var/log/nginx"
  file_match = 'json\.event\.access\.log\.?(?P<Index>\d+)?(\.gz)?'
  differentiator = ["default"]
  