# Ruby filter raises error on event.delete **URL:** \ **Category:** Logstash\ **Created:** [December 6, 2015, 3:08pm UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471 "2015-12-06T15:08:33Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![stefws](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stefws/32/6442_2.png) [@stefws](https://discuss.elastic.co/u/stefws)\ **Post date:** [December 6, 2015, 3:08pm UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/1 "2015-12-06T15:08:33Z")
Got a ruby filter: > ruby { code =\> " > event.delete('message') if event['message'].empty? > > $DROP\_STATS = %w[unwantedstat1 unwantedstat2 unwantedstat3] > event.cancel if event['stat'] and $DROP\_STATS.include?(event['stat']) > " } only ruby complains like this: > Ruby exception occurred: undefined method `delete' for #LogStash::Event:0x4cf922cb {:level=\>:error} how can I remove a field from an event within ruby? ---
**Author:** ![vtst2412](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/vtst2412/32/6228_2.png) [@vtst2412](https://discuss.elastic.co/u/vtst2412)\ **Post date:** [December 6, 2015, 7:53pm UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/2 "2015-12-06T19:53:31Z")
Try: ``` event.remove(field) ``` ---
**Author:** ![stefws](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stefws/32/6442_2.png) [@stefws](https://discuss.elastic.co/u/stefws)\ **Post date:** [December 6, 2015, 8:11pm UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/3 "2015-12-06T20:11:56Z")
[ruby doc](http://ruby-doc.org/core-1.9/Hash.html#method-i-delete) doesn't list remove as an operation of a hash, but delete(field), so... ---
**Author:** ![vtst2412](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/vtst2412/32/6228_2.png) [@vtst2412](https://discuss.elastic.co/u/vtst2412)\ **Post date:** [December 6, 2015, 8:14pm UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/4 "2015-12-06T20:14:30Z")
> [@stefws](#): > > ruby doc doesn't list remove as an operation of a hash, but delete(field), so... The event object is Class: LogStash::Event, not technically a hash. Did you even try before commenting 😄 [http://www.rubydoc.info/gems/logstash-event/1.1.5/LogStash/Event#remove-instance\_method](http://www.rubydoc.info/gems/logstash-event/1.1.5/LogStash/Event#remove-instance_method) ---
**Author:** ![stefws](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stefws/32/6442_2.png) [@stefws](https://discuss.elastic.co/u/stefws)\ **Post date:** [December 6, 2015, 8:45pm UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/5 "2015-12-06T20:45:51Z")
Okay not as you write it's a class variable (will read the doc...) thanks! I'm at it 😉 ---
**Author:** ![stefws](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stefws/32/6442_2.png) [@stefws](https://discuss.elastic.co/u/stefws)\ **Post date:** [December 6, 2015, 8:52pm UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/6 "2015-12-06T20:52:37Z")
event.remove works 👍 ---
**Author:** ![stefws](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stefws/32/6442_2.png) [@stefws](https://discuss.elastic.co/u/stefws)\ **Post date:** [December 8, 2015, 8:38am UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/7 "2015-12-08T08:38:00Z")
That is it doesn't rise an exception/error anymore, but it seems it doesn't get called either due to my if expression as changing it to this shows expression never evaluates to true, any hints why not? > ``` > $DROP_STATS = %w[unwantedstat1 unwantedstat2 unwantedstat3] > if $DROP_STATS.include?(event['stat']) > event['dropped_stat'] = 'found' > event.cancel > end > > ``` ---
**Author:** ![stefws](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stefws/32/6442_2.png) [@stefws](https://discuss.elastic.co/u/stefws)\ **Post date:** [December 8, 2015, 12:43pm UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/8 "2015-12-08T12:43:55Z")
Forget my mistake (naturally 😉 code snippet IS working as expected, just didn't had it in the right execution path to get it triggered. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 5:19am UTC](https://discuss.elastic.co/t/ruby-filter-raises-error-on-event-delete/36471/9 "2017-07-06T05:19:32Z")