Add fields

The add_fields processor adds fields to the event. Fields can be scalar values, arrays, dictionaries, or any nested combination of these. The add_fields processor overwrites the target field if it already exists. By default, the fields that you specify are grouped under the fields sub-dictionary in the event. To group the fields under a different sub-dictionary, use the target setting. To store the fields as top-level fields, set target: ''.

This configuration:

- add_fields:
    target: project
    fields:
      name: myproject
      id: '574734885120952459'

Adds these fields to any event:

{
  "project": {
    "name": "myproject",
    "id": "574734885120952459"
  }
}

This configuration alters the event metadata:

- add_fields:
    target: '@metadata'
    fields:
      op_type: "index"

When the event is ingested by Elasticsearch, the document will have op_type: "index" set as a metadata field.