Struct FixedWindowPolicy 

pub struct FixedWindowPolicy { /* private fields */ }

An anchored fixed-window rate-limit policy.

A backend starts a window on the first allowed check for a storage key. Later allowed checks use that anchor until the full window has elapsed. This differs from fixed wall-clock boundaries such as calendar minutes.

Windows have exact whole-millisecond precision. A policy owns its application-defined identifier and scope so it can be reused by checks.

With the serde feature, the wire object contains id, scope, limit, window_millis, and quota_mode. The derived fingerprint is deliberately omitted and recomputed through FixedWindowPolicy::new when deserializing. An omitted quota_mode defaults to enforcement.

Implementations

impl FixedWindowPolicy

pub fn new( id: PolicyId, scope: ScopeId, limit: u64, window: Duration, ) -> Result<Self, PolicyError>

Validates and constructs an anchored fixed-window policy.

Errors

Returns an error if limit or window is zero, if limit exceeds MAX_LIMIT, if the window is not an exact whole number of milliseconds, or if it exceeds MAX_WINDOW.

pub const fn with_quota_mode(self, quota_mode: QuotaMode) -> Self

Returns this policy with the requested quota deployment mode.

The policy fingerprint is unchanged because the mode is not storage-relevant.

pub const fn id(&self) -> &PolicyId

Returns the application-defined policy identifier.

pub const fn scope(&self) -> &ScopeId

Returns the application-defined policy scope.

pub const fn limit(&self) -> u64

Returns the maximum cost allowed during one window.

pub const fn window(&self) -> Duration

Returns the anchored window duration.

pub const fn window_millis(&self) -> u64

Returns the anchored window as an exact, nonzero millisecond count.

pub const fn fingerprint(&self) -> PolicyFingerprint

Returns the deterministic configuration fingerprint.

pub const fn quota_mode(&self) -> QuotaMode

Returns whether quota exhaustion is enforced or shadowed.

Trait Implementations

impl Clone for FixedWindowPolicy

fn clone(&self) -> FixedWindowPolicy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FixedWindowPolicy

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for FixedWindowPolicy

Available on crate feature serde only.

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for FixedWindowPolicy

impl Hash for FixedWindowPolicy

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for FixedWindowPolicy

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

Equality operator ==.

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

Inequality operator !=.

impl RateLimitPolicy for FixedWindowPolicy

fn id(&self) -> &PolicyId

Returns the application-defined policy identifier.

fn scope(&self) -> &ScopeId

Returns the application-defined policy scope.

fn quota(&self) -> u64

Returns the quota replenished during Self::quota_period.

fn quota_period(&self) -> Duration

Returns the period during which Self::quota is replenished.

fn capacity(&self) -> u64

Returns the largest single cost and maximum immediately available allowance supported by this policy.

fn fingerprint(&self) -> PolicyFingerprint

Returns the deterministic storage-key fingerprint.

fn quota_mode(&self) -> QuotaMode

Returns whether quota exhaustion is enforced or shadowed.

impl Serialize for FixedWindowPolicy

Available on crate feature serde only.

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for FixedWindowPolicy