gistfile1.txt

input {
  tcp {
    'port' => 3333
    'type' => 'router_nginx_logs'
  }

  # Some additional inputs could be here as well
}

filter {
  grok { 
    'patterns_dir' => '/opt/logstash/agent/etc/patterns' 
    'add_tag' => ['router_nginx_logs_extracted'] 
    'match' => ['message', '%{NUMBER:msec}\s+%{IP:client_ip}\s+(%{WORD:remote_user}|-)\s+%{TIMESTAMP_ISO8601:logtime}\s+%{WORD:method} %{NOTSPACE:uri} (?:HTTP/%{NUMBER:version})\s+%{NUMBER:status:int}\s+(?:%{NUMBER:bytes_sent:int})\s+%{QS:referer}\s+%{QS:agent}\s+(%{WORD,country_code}|-)\s+(%{NUMBER:request_time:float}|-)\s+%{QS:http_fwd_for}\s+%{HOST:http_host}\s+(%{WORD:instance_id}|-)'] 
    'type' => 'router_nginx_logs' 
  } 

  date { 
    'type' => 'router_nginx_logs' 
    'match' => ["logtime", "yyyy-MM-dd'T'HH:mm:ssZ"] 
  } 
}

output {
 # Your regular outputs
}