Date parsing, logstash does not take slovene locale

[Mojster]

Log entry:
SEARCH#Android#SLO#sikmb#BIB#sikmb#02-okt-2017 07:04:00.721#ADV##0#0#0#2#8#((šola AND luči)) NOT (DT=D) NOT RS=D and (DP=08 OR DP=XX) NOT NH=1

filter part from pipeline:

grok {
			match => {"message" => "%{DATA:act}\#%{DATA:interface}\#%{DATA:country}\#%{DATA:acronym}\#%{DATA:typeDB}\#%{GREEDYDATA:leftovers}"}
		}
		if [act] == "CONN" {
			drop { }
		}
		ruby {
			code => "event.set('acronym', event.get('acronym').upcase)"
		}
		
		mutate{
			split => {"leftovers" => "#"}
		}
		
		if [act] == "AUTH" {
			mutate{
				add_field => {
					"date" => "%{leftovers[1]}"
					"userID" => "%{leftovers[2]}"
				}
				remove_field => [leftovers]
			}
		} else if [act] == "DISP" {
			mutate{
				add_field => {
					"date" => "%{leftovers[0]}"
					"outputType" => "%{leftovers[1]}"
					"userID" => "%{leftovers[2]}"
				}
				remove_field => [leftovers]
			}
		} else if [act] == "SEARCH" {
			mutate{
#				WORKAROUND ŠUMNIKI
				add_field => {
					"url" => ""
					"date" => "%{leftovers[1]}"
					"mode" => "%{leftovers[2]}"
					"stZadetkov" => "%{leftovers[7]}"
				}
				merge => {"url" => "leftovers[9]"}
				remove_field => [leftovers]
			}
		} else if [act] == "RESR" or [act] == "PROL" or [act] == "CRES" {
			mutate{
				add_field => {
					"date" => "%{leftovers[1]}"
					"userID" => "%{leftovers[2]}"
					"serialNum" => "%{leftovers[3]}"
				}
				remove_field => [leftovers]
			}
		}
		
		date {
			locale => "sl-SI"
			match => ["date", "dd-MMM-YYYY HH:mm:ss.SSS"]
			timezone => "Europe/Ljubljana"
			target => "date"
		}
		
		mutate{
			join => {"url" => ""}
			add_field => {"inputType" => "MCOBISS"}
		}

My problem is, that my date 02-okt-2017 07:04:00.721 is written with using Slovenian locale
http://www.localeplanet.com/java/sl-SI/index.html

I've tried in the locale setting both option sl and sl_SI.

Is there any option to process this or should I just do a gsub and just replace them?

[Mojster]

So I assume there is and will not be a fix for this.

There for I should do the dirty work. Replace mont name with gsub and apply the en locale.

[Mojster]

Found a fix.

Date plugin does not suport Slovenian locale (sl, sl_SI, sl-SI) but a I found out with testing, it does support, Serbian (sr_Latn_RS) and the 3char months are identical.