Struct ProducerCtx 

pub struct ProducerCtx<'a> { /* private fields */ }

Context handed to a producer’s build closure on activation.

Provides:

• Self::node_id / Self::core — identity + Core access for sink callbacks that re-enter Core.
• Self::subscribe_to — subscribe to an upstream Core node; the resulting Subscription is auto-tracked under node_id in the binding’s producer storage and dropped on producer deactivation.

Implementations

impl<'a> ProducerCtx<'a>

pub fn new( node_id: NodeId, core: &'a Core, storage: &'a ProducerStorage, ) -> Self

Construct a new context for the binding’s invoke_fn dispatch to call build closures. Internal — bindings call this; user code receives the constructed ctx via the build closure’s arg.

pub fn node_id(&self) -> NodeId

The producer node’s id.

pub fn core(&self) -> &Core

The Core dispatcher. Sink closures use this to re-enter Core — core.emit(self.node_id(), h) to emit a value, etc.

pub fn subscribe_to(&self, source: NodeId, sink: Sink) -> SubscribeOutcome

Subscribe sink to upstream source. The Subscription is auto-tracked under the producer’s node_id; on producer deactivation, the binding drops the storage entry, which drops the Subscription, which unsubscribes the sink.

Phase H+ STRICT (D115, 2026-05-10): uses try_subscribe to attempt the subscription. On partition order violation, the subscribe is deferred to wave-end via DeferredProducerOp::Callback — the deferred callback runs after all partition wave_owners are released (no partitions held → safe to acquire any partition).

R2.2.7.b (D118, 2026-05-10): if the upstream is non-resubscribable AND already terminated, try_subscribe returns Err(SubscribeError::TornDown). /qa F2 (2026-05-10): the rejection is now surfaced to the caller via SubscribeOutcome::Dead so the operator can apply its per-op dead-source semantics — pre-F2 the rejection was silently swallowed, leaving operators wedged (zip waiting on a queue that would never fill, concat stuck on a source that would never advance, etc.). See SubscribeOutcome::Dead for per-operator guidance.