Channel

TypedBus::Channel

A named, typed pub/sub channel with explicit acknowledgment tracking.

Constructor

Channel.new(name, type:, timeout:, max_pending:, stats:, throttle:)

Parameter	Default	Description
name	required	Symbol channel name
type	nil	Optional class constraint for messages
timeout	30	Seconds before delivery auto-nacks
max_pending	nil	Backpressure limit; nil = unbounded
stats	nil	Optional Stats instance for counters
throttle	0.0	Capacity ratio where backoff begins

channel = TypedBus::Channel.new(:orders,
  type: Order,
  timeout: 10,
  max_pending: 100,
  throttle: 0.5
)

Note

When using channels via MessageBus, these values are resolved through the configuration cascade. You don't normally construct channels directly with all parameters.

Attributes

name → Symbol

Channel name.

type → Class, nil

Type constraint, or nil for untyped channels.

dead_letter_queue → DeadLetterQueue

The channel's dead letter queue.

Pub/Sub

publish(message) → DeliveryTracker, nil

Publish a message to all current subscribers.

• Blocks the calling fiber if bounded and at capacity
• Applies throttle delay if configured
• Returns nil if no subscribers (message goes to DLQ)

Raises: ArgumentError for type mismatches. RuntimeError if closed.

subscribe(&block) → Integer

Subscribe to messages. Returns the subscriber ID.

Raises: RuntimeError if closed.

unsubscribe(id_or_block)

Remove a subscriber by integer ID or block reference.

Query

subscriber_count → Integer

Number of active subscribers.

pending_count → Integer

Number of unresolved delivery trackers.

pending? → Boolean

True when there are unresolved deliveries.

closed? → Boolean

True if the channel has been closed.

Lifecycle

close

Stop accepting new publishes and subscribes. Pending deliveries are force-NACKed and routed to the DLQ.

clear!

Hard reset: cancel all timeout tasks, discard pending state, clear DLQ. Does not mark the channel as closed.