kuilt-session/us.tractat.kuilt.session.admit/AdmitMessage

AdmitMessage

@Serializable

Wire messages that implement the admit/identify handshake.

Framing: each AdmitMessage is CBOR-encoded and sent as a us.tractat.kuilt.core.Swatch payload. The receiver detects admit frames by a discriminator prefix tag (PREFIX_BYTE) that application frames must not start with — this avoids a separate channel or wrapper envelope.

Handshake flow:

Joiner → Host : Hello(identity)
Host   → Joiner : Welcome(assignedId, identity)
Host   → all others : Welcome(assignedId, identity)   [roster broadcast]

If the host rejects the joiner (e.g. already admitted with same dedupKey):

Host → Joiner : Reject(reason)

The host-side runs this passively for incoming Hellos. The joiner sends Hello immediately upon transport connection and waits for Welcome or Reject.

Inheritors

Types

Companion

object Companion

Farewell

@Serializable

@SerialName(value = "farewell")

data class Farewell(val peerId: String, val expired: Boolean = false) : AdmitMessage

Sent by the host to every remaining member when a member departs cleanly (the host received that member's Goodbye).

Goodbye

@Serializable

@SerialName(value = "goodbye")

data object Goodbye : AdmitMessage

Sent by a joiner to the host on a deliberate us.tractat.kuilt.session.Room.leave.

Hello

@Serializable

@SerialName(value = "hello")

data class Hello(val displayName: String, val sessionId: String, val deviceId: String? = null, val targetRoom: String? = null, val protocolVersion: Int? = null) : AdmitMessage

Sent by a joiner to the host immediately after transport connection.

Paused

@Serializable

@SerialName(value = "paused")

data class Paused(val peerId: String, val expiresAt: Long) : AdmitMessage

Sent by the host to every other member when a member's link drops and its seat is being held open — the presence counterpart of Farewell's eviction (#1557).

Reject

@Serializable

@SerialName(value = "reject")

data class Reject(val reason: String, val codeId: String? = null) : AdmitMessage

Sent by the host to reject a joiner's Hello or Resume.

Resume

@Serializable

@SerialName(value = "resume")

data class Resume(val tokenPeerId: String, val tokenRoomId: String, val issuedAt: Long) : AdmitMessage

Sent by a joiner to the host to resume a partitioned session.

ResumeAck

@Serializable

@SerialName(value = "resume-ack")

data object ResumeAck : AdmitMessage

Sent by the host to confirm that a joiner's Resume was accepted.

Unpaused

@Serializable

@SerialName(value = "unpaused")

data class Unpaused(val peerId: String) : AdmitMessage

Sent by the host to every other member when a paused member's link recovered inside its reconnect window — the release counterpart of Paused (#1557).

Welcome

@Serializable

@SerialName(value = "welcome")

data class Welcome(val assignedPeerId: String, val displayName: String, val sessionId: String, val deviceId: String? = null, val roomId: String? = null) : AdmitMessage

Sent by the host to confirm admission.