Struct IngressQueue 

pub struct IngressQueue { /* private fields */ }

Lock-free MPMC ingress queue + waker. Multiple external producers may push concurrently; the engine’s single consumer drains via drain_all on each poll cycle.

Implementations

impl IngressQueue

pub fn new() -> Self

Construct a fresh ingress queue with the default capacity (DEFAULT_INGRESS_CAPACITY).

pub fn with_capacity(capacity: usize) -> Self

Construct a fresh ingress queue with the supplied bounded capacity. Per ENGINE.md §2.2 the canonical sizing is bus_capacity * 4; pass the host’s chosen bus_capacity multiplied by 4 to match.

pub fn completion_result_cap(&self) -> usize

Per-complete() result-byte cap. Defaults to usize::MAX when not configured; apply_config_caps reseeds it from NodeConfig::max_completion_result_bytes.

pub fn push(&self, event: IngressEvent) -> Result<(), IngressEvent>

Push an event. On success returns Ok(()) and wakes the engine if it’s sleeping. On a full queue the event comes back in Err(_) and the dropped_overflow counter is incremented; transport adapters decide whether to retry, drop with a metric, or escalate as back-pressure. The IngressEvent Err variant is large (carries a WireEnvelope with multihash PeerIds); transport adapters already box or re-queue, so the cost lives at the boundary.

pub fn drain_all(&self) -> Vec<IngressEvent>

Drain all available events. Called by the engine on each poll cycle’s ingress drain.

Pre-reserves capacity for the bounded queue’s full length so the drain Vec grows once at construction, not in O(log n) reallocations as events pop. The queue itself caps inflight at self.capacity(); the drain is bounded by the same cap, so the upfront reservation is the exact-fit answer.

pub fn register_waker(&self, waker: &Waker)

Register the engine’s waker so future pushes can wake it.

pub fn is_empty(&self) -> bool

true when the queue currently holds no events.

pub fn len(&self) -> usize

Approximate current queue depth. The underlying concurrent-queue returns an approximate len for the MPMC case; introspection callers should treat this as a snapshot, not a real-time invariant.

pub fn capacity(&self) -> usize

Bounded capacity supplied at construction. concurrent-queue guarantees Some(cap) for bounded queues, so unwrapping is safe for the framework’s path that never builds an unbounded ingress queue.

pub fn dropped_overflow(&self) -> u64

Total events dropped due to the queue being full since this queue was constructed. Telemetry hook for transport adapters

• Node introspection.

Trait Implementations

impl CompletionSink for IngressQueue

fn complete(&self, cmd_id: CommandId, result_bytes: &[u8])

Deliver a successful completion. Implementation copies bytes.

fn fail(&self, cmd_id: CommandId, detail: &str)

Deliver a failure with Display rendering of the error.

impl Default for IngressQueue

fn default() -> Self

Returns the “default value” for a type.