xai-org/x-algorithm · error · ConfigFailure

Field Ids in event type ${config.eventType} are not unique.

Error message

Field Ids in event type ${config.eventType} are not unique.

What it means

ConfigFailure thrown when an event type's inputFeatures contain duplicate fieldId values (the numeric IDs), analogous to the field-name check. Field IDs must be unique within an event type so encoding is unambiguous.

Source

Thrown at botmaker/src/scala/com/twitter/botmaker/runtime/config/EventTypeConfigs.scala:59

trait EventTypeConfigs extends ServiceConfigs {

  final private val eventTypes = mutable.Map[String, BotMakerEventTypeConfig]()

  final def getEventTypes: Map[String, BotMakerEventTypeConfig] = eventTypes.toMap

  final def addEventType(config: BotMakerEventTypeConfig): Option[BotMakerEventTypeConfig] = {

    unique(EventType, config.eventType)
    validateEventType(config.eventType)

    config.inputFeatures.asScala foreach { fc => validateFieldName(fc.fieldName) }

    if (config.inputFeatures.asScala.map(_.fieldName).toSet.size != config.inputFeatures.size) {
      throw ConfigFailure(s"Field names in event type ${config.eventType} are not unique.")
    }

    if (config.inputFeatures.asScala.map(_.fieldId).toSet.size != config.inputFeatures.size) {
      throw ConfigFailure(s"Field Ids in event type ${config.eventType} are not unique.")
    }

    eventTypes.put(config.eventType, config)
  }

  override def debug(dbg: RuntimeDebugger): Unit = {

    super.debug(dbg)

    dbg.open("eventTypes", eventTypes) foreach { d =>
      eventTypes foreach {
        case (name, config) =>
          d.info(name, config.toString)
      }
    }
  }

  override def compilerBuilder[E <: ServiceContainer: ClassTag]: CompilerBuilder[E] = {

View on GitHub (pinned to 24c60942c5)

Solutions

Assign unique fieldId values to every feature in the event type
Audit the feature ID allocation table after merging event types

Example fix

# before
input_features: [{fieldId: 1, fieldName: a}, {fieldId: 1, fieldName: b}]
# after
input_features: [{fieldId: 1, fieldName: a}, {fieldId: 2, fieldName: b}]

Defensive patterns

Strategy: validation

Validate before calling

val ids = config.inputFeatures.asScala.map(_.fieldId)
require(ids.size == ids.toSet.size, s"duplicate fieldIds: ${ids.toSeq.groupBy(identity).filter(_._2.size>1).keys}")

Try / catch

catch { case e: ConfigFailure => report duplicate IDs and the owning features }

Prevention

Allocate field IDs from a single counter/registry
Check ID collisions when copying features between event types

When it happens

Trigger: Two input features sharing the same fieldId in one event type — often after renumbering or merging feature definitions.

Common situations: Appending features with IDs copied from another event type; thrift ID renumbering collisions during schema evolution.

Related errors

AI-assisted analysis of xai-org/x-algorithm@24c60942c5 (2026-08-28). Data as JSON: /api/errors/2587c2cdb7b2a5ad. Report an issue: GitHub.