Event Trigger

Overview

The Event Trigger node starts a workflow run automatically when a named platform event fires (e.g. battle.completed, vote.cast, lens.published). The platform event dispatcher injects the full event payload into __event__ before execution, which the node surfaces as the event output port for downstream nodes. An optional filterExpression is evaluated against the event object; if it returns falsy the run is silently skipped. When triggered manually or in test mode, the node falls back to a typed stub containing an empty data object and the configured eventType string.

Configuration

Field	Type	Required	Description
eventType	enum	Yes	The platform event that activates this workflow. One of: battle.completed, lens.published, workflow.failed, vote.cast, leaderboard.updated. Determines which internal event bus subscription is registered at workflow publish time.
filterExpression	string	No	JavaScript-like expression evaluated against the event object. Must return truthy for the run to proceed. If omitted, all occurrences of the event type trigger a run. Example: event.data.winner_id === ctx.lenserId.

Inputs

Port	Type	Description
—	void	No upstream inputs. This node is always the entry point of the workflow graph.

Outputs

Port	Type	Description
event	json	The matched platform event object. Shape: { type: string, data: string-keyed map, timestamp: string (ISO-8601) }. In manual/test runs a stub with an empty data object is emitted instead.

Example

{
  "nodeType": "event_trigger",
  "config": {
    "nodeType": "event_trigger",
    "config": {
      "eventType": "battle.completed",
      "filterExpression": "event.data.winner_id === ctx.lenserId"
    }
  }
}