Pre-Index a field during Index Creation

I can understand that its possible to preindex a field during index creation as mentioned in the following page :
https://www.elastic.co/guide/en/elasticsearch/reference/master/index-modules-index-sorting.html

In my case I am creating index automatically every day by using date as one parameter. So how do I sort one field in an index which is created automatically by the already configured logstash output file ?

Logstash config :

output {
if [filteredValues] {
 file {
   path => "/etc/logstash/output.json"
   codec => line { format => "CI-ID : %{filteredValues}"}
   write_behavior => overwrite
 }
}
if "lastFailedBuild" in [source] {
  elasticsearch {
hosts => ["xxxxxxxxxxxxx:9200"]
manage_template => false
index => "%{[@metadata][beat]}-%{+YYYY.MM.dd}-failurelogs"
document_type => "%{[@metadata][type]}"
  }
}else if "lastUnsuccessfulBuild" in [source] {
elasticsearch {
hosts => ["xxxxxxxxxx:9200"]
manage_template => false
index => "%{[@metadata][beat]}-%{+YYYY.MM.dd}-failurelogs"
document_type => "%{[@metadata][type]}"
  }

}else {
  elasticsearch {
hosts => ["xxxxxxxxxxxxxxxxx:9200"]
manage_template => false
index => "%{[@metadata][beat]}-%{+YYYY.MM.dd}-successlogs"
document_type => "%{[@metadata][type]}"
  }
}

Thanks in advance.