Document for filebeat configuration

You can check an example here in the documentation.

It is the json part:

{
  "policy": {
    "_meta": {
      "description": "used for nginx log",
      "project": {
        "name": "myProject",
        "department": "myDepartment"
      }
    },
    "phases": {
      "warm": {
        "min_age": "10d",
        "actions": {
          "forcemerge": {
            "max_num_segments": 1
          }
        }
      },
      "delete": {
        "min_age": "30d",
        "actions": {
          "delete": {}
        }
      }
    }
  }
}