#Interface: Channel<T>

A named realtime channel carrying one JSON payload type.

Reliable messages preserve accepted per-recipient order and can be replayed after an interruption or reload for up to five minutes after admission. Retention normally uses service memory; planned updates preserve it, while an unexpected service crash can lose events. Plot.connection.recovery reports known replay gaps. Delivery can occur more than once around a browser interruption, so duplicate-sensitive handlers need a stable action ID. latest samples may be coalesced or dropped and are not a substitute for synchronized state. If a send detects that Plot cannot safely retain a reliable message, it throws a terminal internal-error synchronously. A hold deadline can instead expire after a send has returned. Either failure stops this SDK instance; later valid party or state reads, state writes, and channel sends report the retained error. Reload or exit instead of retrying on the same page.

#Type Parameters

#T

T = unknown

#Methods

#broadcast()

broadcast(payload): void

Sends a message to all eligible party players, including the sender.

Plot owns delivery and reconnect recovery. The method returns void; a successful return is not a receipt that another player handled the message. joining and left players do not receive it. A reliable message can be retained for a temporarily disconnected player; a latest sample may be dropped.

#Parameters

#payload

T

A supported JSON payload to send.

#Returns

void

#Throws

PlotNotReadyError when the complete ready state has not been installed.

#Throws

PlotOperationError when Plot cannot safely retain a reliable message, or after the session, participation, or runtime has ended.

#Throws

TypeError when payload is invalid.

#See

Error handling

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#sendTo()

sendTo(playerId, payload): void

Sends a message to one party player.

Plot owns delivery and reconnect recovery. The method returns void; a successful return is not a receipt that the recipient handled the message. A temporarily disconnected player remains a valid reliable recipient; joining and left players are not valid recipients.

#Parameters

#playerId

number

The stable ID of a connected or disconnected player.

#payload

T

A supported JSON payload to send.

#Returns

void

#Throws

PlotNotReadyError when the complete ready state has not been installed.

#Throws

PlotOperationError when Plot cannot safely retain a reliable message, or after the session, participation, or runtime has ended.

#Throws

TypeError when payload is invalid, or playerId is out of range, unknown, still joining, or belongs to a player who has left.

#See

Error handling

---

#subscribe()

subscribe(listener): Unsubscribe

Subscribes to messages received on this channel.

Channel messages are transient and are delivered to listeners active when the SDK consumes them. Use Plot.gameState, or Plot.playerData for genuinely player-specific data, when state must be readable by code that subscribes later.

Register reliable listeners during startup, before Plot.ready(). This does not start readiness. After readiness, a buffered reliable message may invoke the listener synchronously before this method returns. Listener errors are reported to the browser and do not stop other listeners. All synchronous listeners for a delivery return before the next delivery runs. Returned promises are not awaited: delivery does not confirm an asynchronous state write. Store effects that must survive refresh in synchronized state.

#Parameters

#listener

(message) => void

Receives messages sent on this channel name.

#Returns

Unsubscribe

An idempotent function that stops this subscription.

#Throws

TypeError when listener is not a function.