A subscription runs a flow, function or channel when an event fires. A condition on it decides whether this event qualifies. It isn’t a permission check: events come from the system, not from a caller. It is a filter.

​
In Studio

On a subscription (Logic → Event subscriptions), the field Only when… takes a rule. Filter on the event with rules over $event. Build it in the condition builder.

​
What it can read

​
Examples

Only big orders:
  • Compare values: $event.payload.record.total is greater than 100000
Only when the status changed to paid:
  • Compare values: $event.payload.record.status equals paid
Only sign-ins by password:
  • Compare values: $event.payload.method equals password

​
Cost

The condition is evaluated before the target is queued, so an event that doesn’t match costs almost nothing. Prefer a condition over starting a flow that immediately exits.

​
Events and security

Events carry data. A subscription that publishes to a channel or sends an outbound webhook sends that payload to whoever listens. Don’t forward more than the receiver should see: filter fields in the flow, so the payload holds only what the audience should see.

Events

The event system.

Operators

Write the condition.