﻿---
title: Filter and enhance data with processors
description: You can define processors in your configuration to process events before they are sent to the configured output. The libbeat library provides processors...
url: https://www.elastic.co/elastic/docs-builder/docs/2564/reference/beats/winlogbeat/filtering-enhancing-data
products:
  - Beats
  - Winlogbeat
applies_to:
  - Elastic Stack: Generally available in 9.0+
---

# Filter and enhance data with processors
You can [define processors](https://www.elastic.co/elastic/docs-builder/docs/2564/reference/beats/winlogbeat/defining-processors) in your configuration to process events before they are sent to the configured output. The libbeat library provides processors for:
- reducing the number of exported fields
- enhancing events with additional metadata
- performing additional processing and decoding

Each processor receives an event, applies a defined action to the event, and returns the event. If you define a list of processors, they are executed in the order they are defined in the Winlogbeat configuration file.
```yaml
event -> processor 1 -> event1 -> processor 2 -> event2 ...
```

<important>
  It’s recommended to do all drop and renaming of existing fields as the last step in a processor configuration. This is because dropping or renaming fields can remove data necessary for the next processor in the chain, for example dropping the `source.ip` field would remove one of the fields necessary for the `community_id` processor to function. If it’s necessary to remove, rename or overwrite an existing event field, please make sure it’s done by a corresponding processor ([`drop_fields`](https://www.elastic.co/elastic/docs-builder/docs/2564/reference/beats/winlogbeat/drop-fields), [`rename`](https://www.elastic.co/elastic/docs-builder/docs/2564/reference/beats/winlogbeat/rename-fields) or [`add_fields`](https://www.elastic.co/elastic/docs-builder/docs/2564/reference/beats/winlogbeat/add-fields)) placed at the end of the processor list defined in the input configuration.
</important>

For example, the following filter configuration drops a few fields that are rarely used (`provider_guid`, `process_id`, `thread_id`, and `version`) and one nested field, `event_data.ErrorSourceTable`:
```yaml
processors:
  - drop_fields:
      fields: [winlog.provider_guid, winlog.process.pid, winlog.process.thread.id, winlog.version, winlog.event_data.ErrorSourceTable]
```