Wrong argument type string expected Timestamp

[morpheus]

Greetings,

I have seen other similar threads to this but not able to solve my problem, I am getting the error:

[2020-01-22T10:45:38,409][WARN ][logstash.inputs.gelf ] Gelf (tcp): client socket failed. {:exception=>#<TypeError: wrong argument type String (expected LogStash::Timestamp)>, :backtrace=>["org/logstash/ext/JrubyEventExtLibrary.java:95:in `set'", "/usr/share/logstash/vendor/bundle/jruby/2.5.0/gems/logstash-input-gelf-3.2.0/lib/logstash/inputs/gelf.rb:281:in `block in strip_leading_underscore'", "org/jruby/RubyArray.java:1792:in `each'", "/usr/share/logstash/vendor/bundle/jruby/2.5.0/gems/logstash-input-gelf-3.2.0/lib/logstash/inputs/gelf.rb:279:in `strip_leading_underscore'", "/usr/share/logstash/vendor/bundle/jruby/2.5.0/gems/logstash-input-gelf-3.2.0/lib/logstash/inputs/gelf.rb:161:in `block in tcp_listener'"]}

When I turn off the winlogbeats prefix to send in GELF format. So before the fields it is sending look like this:

WITH PREFIX (works)

timestamp":1.579706245057E9
winlogbeat @timestamp":“2020-01-22T15:17:25.057Z
_timestamp”:"2020-01-22T15:17:25.057Z

WITHOUT PREFIX (doesn’t work)

timestamp":1.579703908066E9
_timestamp":“2020-01-22T14:38:28.066Z
_@timestamp”:"2020-01-22T14:38:28.066Z

How do I know which field is causing Logstash its issues and reference that field in order to correct it?

Many Thanks.

[Badger]

@morpheus

How do I know which field is causing Logstash its issues

The code is removing the leading underscore from the fieldname. You appear to have a field called _@timestamp, so that would result in a field called @timestamp. I think logstash expect @timestamp to be a LogStash::Timestamp, not a string.