Can't add_field %{host} for udp

[slatemine]

bug / inconsistency: For the config below:

• TCP adds a field with the IP address, eg { ... "logHost" => "127.0.0.1" }
• UDP adds the literal "%{host}", eg { ... "logHost" -> "%{host}" }

input {
  tcp {
    port => "514"
    add_field => { 
        "logHost" => "%{host}"
    }
  }
  udp {
    port => "514"
    add_field => { 
        "logHost" => "%{host}"
    }
  }
}

I add this field to make auditing / monitoring logging coverage easier.

The fix is simple, decorate is being called before event["host"] is being set.
patch.txt

[heiparta]

This issue seems to be fixed: https://github.com/logstash-plugins/logstash-input-udp/blob/master/lib/logstash/inputs/udp.rb#L120

Can be closed?

[slatemine]

I have just retested with 5.6.5 as was upgrading and the problem persists.

The issues is not that host does not exist after input it is that it does not exist when add field is called.