Zabbix and multi_value key

Hi all,
I'm trying to setup the zabbix plugin with the multi_values key without success. This is the config

filter {
add_field => { "multivalue" => [ "foo", "bar" ] }
}

output {
zabbix{
zabbix_server_host => "zabbix_host"
zabbix_server_port => "10051"
zabbix_host => host
multi_value => multivalue
}

Unfortunately, I'm receiving the following error:

[...]
config LogStash::Outputs::Zabbix/@multi_value = ["multivalue"] {:level=>:debug, :file=>"logstash/config/mixin.rb", :line=>"154", :method=>"config_init"}
[...]
Pipeline aborted due to error {:exception=>"LogStash::ConfigurationError", :backtrace=>["/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-zabbix-3.0.1/lib/logstash/outputs/zabbix.rb:101:in `register'"[...]

It seems as if instead of using the field is using the field's name "multivalue"

I'm new to logstash, maybe the

add_field => { "multivalue" => [ "foo", "bar" ] }

is not valid?
How can I create the array in the filter section?

Thanks

You may be overthinking this. multi_value as a setting needs to be an array of field names, not a field which has an array value. See: https://www.elastic.co/guide/en/logstash/current/plugins-outputs-zabbix.html#plugins-outputs-zabbix-multi_value

Use the multi_value directive to send multiple key/value pairs. This can be thought of as an array, like:

[ zabbix_key1, zabbix_value1, zabbix_key2, zabbix_value2, ... zabbix_keyN, zabbix_valueN ]

…where zabbix_key1 is an instance of zabbix_key, and zabbix_value1 is an instance of zabbix_value. If the field referenced by any zabbix_key or zabbix_value does not exist, that entry will be ignored.

Ok thanks, I was hoping to use a field even then (maybe it could be an improvement?)
I am trying to use logstash as a link between collectd and Zabbix.. Is working, but I was hoping it was more linear. Thanks again