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log

Emits a structured log line. message is a JSONLogic expression (a plain string is valid), and fields attaches more JSONLogic-derived key/values.

Synopsis

{
  "name": "log",
  "input": {
    "message": "Order processed",
    "level": "info",
    "fields": {
      "order_id": {
        "var": "data.order.id"
      }
    }
  }
}

Description

log is an engine built-in from dataflow-rs. Orion declares no input schema for it, so a mistake in input surfaces when the task runs rather than when the workflow is saved.

Retry safety: pure. An engine built-in reads and writes the message and nothing else.

Fields

FieldTypeRequiredDefaultDescription
messageJSONLogicyesThe log message (string literal or expression)
levelstringno"info"trace | debug | info | warn | error
fieldsobjectno{}Map of name → JSONLogic expression, logged as structured fields

Examples

{
  "name": "log",
  "input": {
    "level": "info",
    "message": "Order processed",
    "fields": { "order_id": { "var": "data.order.id" } }
  }
}

Last verified 14 September 2026