Enum LimitOutcome 

#[non_exhaustive]
pub enum LimitOutcome {
    Allow,
    ThroughputReject(String),
    WhitelistReject(String),
    ValueReject(String),
    Typed(LimitReason),
}

限额检查结果

v1.4.36 Bug #1 扩展：拒绝类型区分 Throughput vs Whitelist vs Value， 让 REST / gRPC middleware 能把不同类型映射到正确的 HTTP status：

• Throughput（速率 / 日累计 / 时间窗）→ HTTP 429 Too Many Requests 客户端按 rate-limit 语义 backoff 重试即可
• Whitelist（market / symbol / trd_side / acc_id 不在白名单）→ HTTP 403 Forbidden 客户端不该重试，是权限问题，需要改 key / 改请求参数
• Value（单笔上限超 / NaN / inf / 负数）→ HTTP 403 Forbidden 同 Whitelist，不该重试；需要拆单或换 key

v1.4.106 codex 0542 F2 [P2 SECURITY]: *Reject(String) variants 现承载 audit_message() (内部 full-detail). client surface 应通过新 LimitReason 字段拿 public_message() (terse, no cap leak). 见 Self::reason_typed.

老代码用 Reject(String)，保留作向后兼容 —— 但新检查应返对应 *Reject 类型。

v1.4.106 codex 0538 F1 (P1 SECURITY): ValueReject 内部带结构化原因， 让 fail-closed validation (NaN / inf / negative) 与 normal cap-exceeded 区分；display 消息仍 backward-compat 字符串格式。

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Allow

ThroughputReject(String)

速率 / 日累计 / 时间窗类拒绝（429 语义：客户端应 backoff 重试）. String = LimitReason::audit_message().

WhitelistReject(String)

白名单类拒绝（403 语义：权限问题，不该重试）. String = LimitReason::audit_message().

ValueReject(String)

金额上限拒绝（403 语义：不该重试；拆单或换 key）. String = LimitReason::audit_message().

Typed(LimitReason)

v1.4.106 codex 0542 F2: typed reject — 推荐新代码用此 variant, caller 通过 LimitReason::public_message() / audit_message() / metric_label() 各自取所需视图. 与三个老 String variant 共存 (新代码 emit Typed, 老代码 emit *Reject(String) 仍工作).

Implementations

impl LimitOutcome

pub fn is_allow(&self) -> bool

是否拒绝（!is_allow 等价于“拒绝“）

pub fn reason(&self) -> Option<String>

拒绝时的 reason 字符串（Allow 返 None）.

v1.4.106 codex 0542 F2 调整: 现返 Option<String> (老 Option<&str> 兼容性 break, 但所有内部 caller 用 format!("{reason}") 不受影响). 走 Self::public_message 取 client surface 安全形式.

pub fn reason_typed(&self) -> Option<&LimitReason>

v1.4.106 codex 0542 F2: typed reason (若 Typed(r) variant), 否则 None.

pub fn public_message(&self) -> Option<String>

v1.4.106 codex 0542 F2: client-surface terse message.

pub fn metric_label(&self) -> Option<&'static str>

v1.4.106 codex 0542 F2: prometheus metric_label (8 固定桶) 若 typed.

pub fn http_status_code(&self) -> u16

适合此拒绝类型的 HTTP 状态码（REST / gRPC middleware 用）

• Allow → 200
• Throughput / typed throughput → 429
• Whitelist / Value / typed whitelist/value → 403

Trait Implementations

impl Clone for LimitOutcome

fn clone(&self) -> LimitOutcome

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LimitOutcome

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

Formats the value using the given formatter.

impl PartialEq for LimitOutcome

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for LimitOutcome