Enum ApiError 

#[non_exhaustive]
pub enum ApiError<AssetKey = AssetIndex, InstrumentKey = InstrumentIndex> {
    AssetInvalid(AssetKey, String),
    InstrumentInvalid(InstrumentKey, String),
    RateLimit,
    Unauthenticated(String),
    BalanceInsufficient(AssetKey, String),
    OrderRejected(String),
    OrderAlreadyCancelled,
    OrderAlreadyFullyFilled,
}

Represents all API errors generated by an exchange.

These typically indicate a request is invalid for some reason (eg/ BalanceInsufficient). Most variants are not transient — the same request will fail identically on retry. The exception is RateLimit, which is transient.

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.

AssetInvalid(AssetKey, String)

Provided asset identifier is invalid or not supported.

For example:

• The AssetNameExchange was an invalid format.

Not transient — do not retry. The asset identifier must be corrected.

InstrumentInvalid(InstrumentKey, String)

Provided instrument identifier is invalid or not supported.

For example:

• The exchange does not have a market for an instrument.
• The InstrumentNameExchange was an invalid format.

Not transient — do not retry. The instrument identifier must be corrected.

RateLimit

Request was rejected due to rate limiting.

The exchange enforces request quotas and the caller has exceeded them. Some exchanges provide a Retry-After header or similar hint; the client may incorporate this into internal retry logic before surfacing this error.

Transient — retry with backoff. Typical backoff is 10-60 seconds, but respect exchange-specific guidance if available.

Unauthenticated(String)

Authentication failed (invalid credentials, expired key, bad signature).

Unlike other API errors which affect a single request, authentication failures indicate that all subsequent requests will fail until credentials are corrected. Callers should halt trading and alert operators.

Not transient — do not retry. Fix credentials and restart.

BalanceInsufficient(AssetKey, String)

Balance of an asset is insufficient to execute the requested operation.

Warning: AssetKey field may hold an instrument name, not an asset name

Some ExecutionClient implementations (e.g. BinanceSpot) populate the AssetKey field with the instrument name (e.g. "BTCUSDT") rather than the specific low-balance asset (e.g. "BTC" or "USDT"), because splitting a symbol into base/quote requires exchange symbol-info metadata not available at error-parse time. Do not pattern-match on the AssetKey value to identify the specific low-balance asset — use the String field for diagnostics only.

Not transient — do not retry the same request. Reduce order size or deposit additional funds.

OrderRejected(String)

Order was rejected by the exchange for a business rule violation.

Common causes include: price outside allowed range, quantity below minimum, post-only order would cross, reduce-only with no position.

Not transient — do not retry the same request. Adjust order parameters.

OrderAlreadyCancelled

Cancel request failed because the order was already cancelled.

This is a state conflict, not an error per se — the desired end state (order cancelled) has already been achieved.

Not transient — do not retry. The order is already in the cancelled state.

OrderAlreadyFullyFilled

Cancel request failed because the order was already fully filled.

This is a state conflict — the order completed before the cancel arrived. The caller should reconcile their local state with the fill.

Not transient — do not retry. The order no longer exists to cancel.

Trait Implementations

impl<AssetKey: Clone, InstrumentKey: Clone> Clone for ApiError<AssetKey, InstrumentKey>

fn clone(&self) -> ApiError<AssetKey, InstrumentKey>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<AssetKey: Debug, InstrumentKey: Debug> Debug for ApiError<AssetKey, InstrumentKey>

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

Formats the value using the given formatter.

impl<'de, AssetKey, InstrumentKey> Deserialize<'de> for ApiError<AssetKey, InstrumentKey>

where AssetKey: Deserialize<'de>, InstrumentKey: Deserialize<'de>,

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<AssetKey, InstrumentKey> Display for ApiError<AssetKey, InstrumentKey>

where AssetKey: Display, InstrumentKey: Display,

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

Formats the value using the given formatter.

impl<AssetKey: Eq, InstrumentKey: Eq> Eq for ApiError<AssetKey, InstrumentKey>

impl<AssetKey, InstrumentKey> Error for ApiError<AssetKey, InstrumentKey>

where Self: Debug + Display,

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl<AssetKey, InstrumentKey> From<ApiError<AssetKey, InstrumentKey>> for ClientError<AssetKey, InstrumentKey>

fn from(source: ApiError<AssetKey, InstrumentKey>) -> Self

Converts to this type from the input type.

impl<AssetKey, InstrumentKey> From<ApiError<AssetKey, InstrumentKey>> for OrderError<AssetKey, InstrumentKey>

fn from(source: ApiError<AssetKey, InstrumentKey>) -> Self

Converts to this type from the input type.

impl<AssetKey: Hash, InstrumentKey: Hash> Hash for ApiError<AssetKey, InstrumentKey>

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<AssetKey: Ord, InstrumentKey: Ord> Ord for ApiError<AssetKey, InstrumentKey>

fn cmp(&self, other: &ApiError<AssetKey, InstrumentKey>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl<AssetKey: PartialEq, InstrumentKey: PartialEq> PartialEq for ApiError<AssetKey, InstrumentKey>

fn eq(&self, other: &ApiError<AssetKey, InstrumentKey>) -> 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<AssetKey: PartialOrd, InstrumentKey: PartialOrd> PartialOrd for ApiError<AssetKey, InstrumentKey>

fn partial_cmp( &self, other: &ApiError<AssetKey, InstrumentKey>, ) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<AssetKey, InstrumentKey> Serialize for ApiError<AssetKey, InstrumentKey>

where AssetKey: Serialize, InstrumentKey: Serialize,

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl<AssetKey: PartialEq, InstrumentKey: PartialEq> StructuralPartialEq for ApiError<AssetKey, InstrumentKey>