What causes "Unknown CaptureTriggerKind: ${kind}" in windmill-labs/windmill?

Add the missing kind to the switch statement in captureTriggerKindToTriggerKind (and to the CaptureTriggerKind union).

Unknown CaptureTriggerKind: ${kind}

Error message

Unknown CaptureTriggerKind: ${kind}

What it means

captureTriggerKindToTriggerKind maps a CaptureTriggerKind (used by capture/install flows) to the UI TriggerKind. Any kind outside the exhaustive switch (webhook, email, default_email, http, websocket, kafka, nats, mqtt, amqp, sqs, postgres, gcp) hits the default branch and throws. It is a guard against unknown/unsupported capture trigger kinds reaching the UI.

Source

Thrown at frontend/src/lib/components/triggers.ts:91

			return 'routes'
		case 'websocket':
			return 'websockets'
		case 'kafka':
			return 'kafka'
		case 'nats':
			return 'nats'
		case 'mqtt':
			return 'mqtt'
		case 'amqp':
			return 'amqp'
		case 'sqs':
			return 'sqs'
		case 'postgres':
			return 'postgres'
		case 'gcp':
			return 'gcp'
		default:
			throw new Error(`Unknown CaptureTriggerKind: ${kind}`)
	}
}

View on GitHub (pinned to e474e8803c)

Solutions

Add the missing kind to the switch statement in captureTriggerKindToTriggerKind (and to the CaptureTriggerKind union).
Check the version skew: if the data comes from a newer backend, upgrade the frontend.
Inspect the offending `kind` value in the error message and correct the capture config/project bundle.
Update the shared enum/type definitions so the compiler flags unmapped kinds.

Example fix

// before
case 'gcp':
  return 'gcp'
default:
  throw new Error(`Unknown CaptureTriggerKind: ${kind}`)
// after
case 'gcp':
  return 'gcp'
case 'azure':
  return 'azure'
default:
  console.warn(`Unknown CaptureTriggerKind: ${kind}, skipping`)
  return undefined

Defensive patterns

Strategy: type-guard

Validate before calling

const KNOWN: ReadonlySet<string> = new Set(['webhook','email','default_email','http','websocket','kafka','nats','mqtt','amqp','sqs','postgres','gcp'])
function isKnownCaptureKind(kind: string): boolean {
  return KNOWN.has(kind)
}

Type guard

function isCaptureTriggerKind(k: string): k is CaptureTriggerKind {
  return ['webhook','email','default_email','http','websocket','kafka','nats','mqtt','amqp','sqs','postgres','gcp'].includes(k)
}

Try / catch

try {
  const triggerKind = captureTriggerKindToTriggerKind(kind)
} catch (e) {
  console.warn('Skipping unknown captured trigger kind', kind)
  return
}

Prevention

Keep the CaptureTriggerKind union and the switch in sync — add both when adding a kind
Validate imported/captured data kinds before mapping
Check for frontend/backend version skew when data comes from another deployment
Never feed unvalidated strings from templates or storage into the mapper

When it happens

Trigger: handleClick on a captured trigger whose `kind` string is not one of the 12 supported values — e.g. a kind added to the capture payload but not to this mapper, a typo, or stale data from an older/other version.

Common situations: Importing a project bundle produced by a newer Windmill version that supports extra trigger kinds; hand-edited capture configs; backend/frontend version skew during upgrades.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

AI-assisted analysis of windmill-labs/windmill@e474e8803c (2026-09-03). Data as JSON: /api/errors/06441b220e8be07d. Report an issue: GitHub.