Struct CircuitStats 

pub struct CircuitStats { /* private fields */ }

Circuit breaker statistics for tracking state transitions.

Maintains a rolling window of successes and failures to determine when the circuit should open, close, or enter half-open state.

Implementations

impl CircuitStats

pub fn new() -> Self

Create new circuit stats in the closed state.

pub fn state(&self) -> CircuitState

Get the current circuit state.

pub fn opened_at(&self) -> Option<u64>

Get the timestamp when the circuit opened (if open).

pub fn last_state_change(&self) -> u64

Get the timestamp of the last state change.

pub fn consecutive_failures(&self) -> u32

Get the consecutive failure count.

pub fn error_rate(&self) -> f64

Get the error rate in the current window (0.0-1.0).

pub fn record_success(&mut self)

Record a successful operation.

In closed state: resets consecutive failures, increments window successes. In half-open state: increments consecutive successes.

pub fn record_failure(&mut self)

Record a failed operation.

Increments consecutive failures and window failures. In half-open state, resets consecutive successes.

pub fn should_open(&self, config: &CircuitBreakerConfig) -> bool

Check if the circuit should open based on config thresholds.

Returns true if:

• Consecutive failures exceed threshold, OR
• Error rate exceeds threshold (with minimum sample size)

pub fn should_half_open(&self, config: &CircuitBreakerConfig) -> bool

Check if the circuit should transition to half-open.

Returns true if the circuit is open and the cooldown period has elapsed.

pub fn should_close(&self, config: &CircuitBreakerConfig) -> bool

Check if the circuit should close.

Returns true if in half-open state and consecutive successes meet or exceed the success threshold.

pub fn can_probe(&self, config: &CircuitBreakerConfig) -> bool

Check if a probe request can be made in half-open state.

Returns true if active probes are below the maximum allowed.

pub fn start_probe(&mut self, config: &CircuitBreakerConfig) -> bool

Start a probe request in half-open state.

Returns true if the probe was started, false if already at max probes.

pub fn open(&mut self)

Transition the circuit to open state.

pub fn half_open(&mut self)

Transition the circuit to half-open state.

pub fn close(&mut self)

Transition the circuit to closed state.

pub fn reset_window(&mut self)

Reset the rolling window counters.

Called periodically to ensure the window reflects recent activity.

pub fn recent_results(&self) -> &[bool]

Get recent health check results for history visualization.

Returns a slice of recent results (true=success, false=failure), with the most recent result at the end.

pub fn recovery_remaining_secs( &self, config: &CircuitBreakerConfig, ) -> Option<u64>

Calculate seconds remaining until circuit auto-transitions to half-open.

Returns None if circuit is not open or cooldown has already elapsed.

Trait Implementations

impl Clone for CircuitStats

fn clone(&self) -> CircuitStats

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CircuitStats

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

Formats the value using the given formatter.

impl Default for CircuitStats

fn default() -> CircuitStats

Returns the “default value” for a type.