Struct DiscardedUsage 

pub struct DiscardedUsage { /* private fields */ }

A UsageSlot that discards the event and counts it.

The reference implementation for an integration that has not reached usage export yet, in the same spirit as NoGate for CapacityGate: it lets an embedder adopt admission one stage at a time instead of taking the client runtime and a background writer purely to satisfy a type.

It counts what it discarded, deliberately. A silently dropping slot makes “usage is not wired up” indistinguishable from “no usage happened”, and those are very different operational stories — one of them means an integration is admitting billable work and losing the record of it.

Not for production billing. Discarded events are not recoverable; use the batching writer once usage must be durable.

Deliberately no Default. A zero-valued counter would make Default::default() and new() the same value, leaving a mutant no test can distinguish; an equivalent mutant is a design smell rather than a coverage gap. new returning Arc<Self> also keeps clippy’s new_without_default inapplicable, so the two gates agree rather than pulling opposite ways.

let discarded = DiscardedUsage::new();
// hand `discarded.slot()` to `admit`; assert on the count later
assert_eq!(discarded.count(), 0);

Implementations

impl DiscardedUsage

pub fn new() -> Arc<Self>

A shared counter, ready to hand out slots.

Returns Arc<Self> because that is the only useful form: Self::slot needs one, and a bare DiscardedUsage can do nothing. Making the reachable shape the only constructible one removes a step an embedder would otherwise have to know to take.

pub fn slot(self: &Arc<Self>) -> DiscardedUsageSlot

A slot that discards one event into this counter.

pub fn count(&self) -> u64

How many events have been discarded.

Trait Implementations

impl Debug for DiscardedUsage

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.