Replace fields from events

The replace processor takes a list of fields to search for a matching value and replaces the matching value with a specified string.

The replace processor cannot be used to create a completely new value.

Tip

You can use this processor to truncate a field value or replace it with a new string value. You can also use this processor to mask PII information.

Example

The following example changes the path from /usr/bin to /usr/local/bin:

		- replace:
    fields:
      - field: "file.path"
        pattern: "/usr/"
        replacement: "/usr/local/"
    ignore_missing: false
    fail_on_error: true

	

Elastic Agent processors execute before ingest pipelines, which means that your processor configurations cannot refer to fields that are created by ingest pipelines or Logstash. For more limitations, refer to What are some limitations of using processors?

Name	Required	Default	Description
`fields`	Yes		List of one or more items. Each item contains a `field: field-name`, `pattern: regex-pattern`, and `replacement: replacement-string`, where: * `field` is the original field name. You can use the `@metadata.` prefix in this field to replace values in the event metadata instead of event fields. * `pattern` is the regex pattern to match the field’s value * `replacement` is the replacement string to use to update the field’s value
`ignore_missing`	No	`false`	Whether to ignore missing fields. If `true`, no error is logged if the specified field is missing.
`fail_on_error`	No	`true`	Whether to fail replacement of field values if an error occurs.If `true` and there’s an error, the replacement of field values is stopped, and the original event is returned.If `false`, replacement continues even if an error occurs during replacement.

See Conditions for a list of supported conditions.

Replace fields from events

Example

Configuration settings