# Can't make the "aggregate" filter to work

**URL:** <https://discuss.elastic.co/t/cant-make-the-aggregate-filter-to-work/36725>\
**Category:** Logstash\
**Created:** [December 9, 2015, 10:27am UTC](https://discuss.elastic.co/t/cant-make-the-aggregate-filter-to-work/36725 "2015-12-09T10:27:19Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Benoit\_Chauvet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/benoit_chauvet/32/6004_2.png) [@Benoit\_Chauvet](https://discuss.elastic.co/u/Benoit_Chauvet)\
**Post date:** [December 9, 2015, 10:27am UTC](https://discuss.elastic.co/t/cant-make-the-aggregate-filter-to-work/36725/1 "2015-12-09T10:27:19Z")

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Hi there,

I'd like to use `aggregate` filter to gather informations from different log lines, but I'm not able to make it write anything in the logs.

I tried to add the following lines in my logstash configuration :

```auto
filter {
    aggregate { task_id=>"test" code=>"event['test']='OK'" }
}

```

but the `test` field is not added in my logs.  
According to the [documentation](https://www.elastic.co/guide/en/logstash/current/plugins-filters-aggregate.html)this should work that way, right ?

Thanks for your help

(Note : I use logstash v 2.0)

---

<div class="post-metadata">

**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/cant-make-the-aggregate-filter-to-work/36725/2 "2017-07-06T05:19:24Z")

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