Struct BreakerPolicy 

pub struct BreakerPolicy {
    pub failures: Option<NonZeroU64>,
    pub cooldown: DurationMs,
    pub window: Option<DurationMs>,
    pub failure_rate: Option<f64>,
    pub min_calls: Option<NonZeroU32>,
}

breaker = { failures, cooldown, window, failure_rate, min_calls }.

Two modes per the frozen schema ($defs/breaker), enforced identically by the real core and every stub — normative rules in conformance/README.md:

• count mode: selected when failures is set (or no rate knob is set; failures then defaults to 5) — failures consecutive terminal failures open the breaker.
• rate mode: selected when failures is absent and both window and failure_rate are set — trips when the trailing window holds at least min_calls outcomes (default 10) with failed/total >= failure_rate.

A rate-mode knob without both window and failure_rate (and without failures) is rejected at deserialize time (KEEL-E001): a half-configured mode must fail loudly, never silently degrade to count-mode defaults.

Fields

failures: Option<NonZeroU64>

Count-mode threshold. None means “not set by the user” — see BreakerPolicy::mode for how that selects the mode.

cooldown: DurationMs

window: Option<DurationMs>

failure_rate: Option<f64>

min_calls: Option<NonZeroU32>

Implementations

impl BreakerPolicy

pub const DEFAULT_FAILURES: NonZeroU64

Schema default for count mode’s failures.

pub const DEFAULT_MIN_CALLS: NonZeroU32

Schema default for rate mode’s min_calls.

pub fn mode(&self) -> BreakerMode

The mode this policy selects (schema: “Setting failures selects count mode”), with defaults applied. Deserialization already rejected half-configured rate mode, so window+failure_rate are either both present or irrelevant here.

pub fn has_inert_rate_knobs(&self) -> bool

Whether count mode was selected while rate-mode knobs are present — those knobs are inert (the schema’s precedence), which callers may want to surface loudly rather than leave silent.

Trait Implementations

impl Clone for BreakerPolicy

fn clone(&self) -> BreakerPolicy

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BreakerPolicy

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

Formats the value using the given formatter.

impl Default for BreakerPolicy

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for BreakerPolicy

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for BreakerPolicy

fn eq(&self, other: &BreakerPolicy) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for BreakerPolicy