Reference a value from new added field within grok match setting

[mstojanovic (Milos)]

Hi,

I'm trying to reference a value from a new field that was added with mutate plugin. I try to reference it within a grok match settings.

Part of the filter pipeline looks like:

filter {
      mutate {
         add_field    => {
           "field_1"           => "aws"
           "field_2"           => "test"
           "field_3"             => "%{container_name}"
         }
     }
    if [field_1] and [field_2] and [field_3] != "" {
      grok {
         match => [ "log", "(\w{3}\s\d{2}\s\d{2}:\d{2}:\d{2})\s([^\s]+)\s(somestring\.)[field_1].*"]
      }
   }
}
output { stdout {} }

I have tried to reference a field with following options:

match => [ "log", "(\w{3}\s\d{2}\s\d{2}:\d{2}:\d{2})\s([^\s]+)\s(somestring\.)[field_1].*"]
match => [ "log", "(\w{3}\s\d{2}\s\d{2}:\d{2}:\d{2})\s([^\s]+)\s(somestring\.)[[field_1]].*"]
match => [ "log", "(\w{3}\s\d{2}\s\d{2}:\d{2}:\d{2})\s([^\s]+)\s(somestring\.)%{field_1}.*"]
match => [ "log", "(\w{3}\s\d{2}\s\d{2}:\d{2}:\d{2})\s([^\s]+)\s(somestring\.)%{[field_1]}.*"]
match => [ "log", "(\w{3}\s\d{2}\s\d{2}:\d{2}:\d{2})\s([^\s]+)\s(somestring\.)[field_1].*"]
match => [ "log", "(\w{3}\s\d{2}\s\d{2}:\d{2}:\d{2})\s([^\s]+)\s(somestring\.)([field_1].*)"]

Can anyone help and suggest how else I can try to reference a new added field value through match setting in grok filter plugin?

Thanks