# Fields splitting from kv filter not containing blank values

**URL:** <https://discuss.elastic.co/t/fields-splitting-from-kv-filter-not-containing-blank-values/211613>\
**Category:** Logstash\
**Created:** [December 12, 2019, 10:19am UTC](https://discuss.elastic.co/t/fields-splitting-from-kv-filter-not-containing-blank-values/211613 "2019-12-12T10:19:47Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Vaibhav\_Gupta2](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/vaibhav_gupta2/32/59260_2.png) [@Vaibhav\_Gupta2](https://discuss.elastic.co/u/Vaibhav_Gupta2)\
**Post date:** [December 12, 2019, 10:19am UTC](https://discuss.elastic.co/t/fields-splitting-from-kv-filter-not-containing-blank-values/211613/1 "2019-12-12T10:19:47Z")

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I am using 'kv' filter in logstash like this

kv {  
source =\> "request"  
field\_split =\> "&?"  
}

I have a message like "key=value&key1=&key2=value2"

the logstash output is coming like this

"key" : "value"  
"key1" : "&key2=value2"

But it should be like this

"key" : "value"  
"key1" : ""  
"key2" : "value2"

Can somebody suggest how can we achieve this?

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<div class="post-metadata">

**Author:** ![Badger](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/badger/32/25190_2.png) [@Badger](https://discuss.elastic.co/u/Badger)\
**Post date:** [December 12, 2019, 2:54pm UTC](https://discuss.elastic.co/t/fields-splitting-from-kv-filter-not-containing-blank-values/211613/2 "2019-12-12T14:54:53Z")

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You could use default\_keys to set the value of key1, but a kv filter parsing dynamic keys will not retain blank values.

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<div class="post-metadata">

**Author:** ![Vaibhav\_Gupta2](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/vaibhav_gupta2/32/59260_2.png) [@Vaibhav\_Gupta2](https://discuss.elastic.co/u/Vaibhav_Gupta2)\
**Post date:** [December 12, 2019, 4:54pm UTC](https://discuss.elastic.co/t/fields-splitting-from-kv-filter-not-containing-blank-values/211613/3 "2019-12-12T16:54:00Z")

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I can not use default\_keys because the real message is search query and it can be dynamic and contains any no of fields

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<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:** [January 9, 2020, 4:59pm UTC](https://discuss.elastic.co/t/fields-splitting-from-kv-filter-not-containing-blank-values/211613/4 "2020-01-09T16:59:28Z")

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