Enum ErrorKind 

#[non_exhaustive]
pub enum ErrorKind {
    Network,
    Protocol,
    Auth,
    RateLimit,
    Client,
}

Coarse-grained classification of the source of a MarketDataError.

Returned by MarketDataError::source_kind so downstream code can branch on the category of failure (network glitch vs SDK / protocol bug vs auth vs rate-limit vs caller-side validation) without pattern-matching every variant or string-matching the embedded msg.

#[non_exhaustive] so future variants are non-breaking.

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.

Network

Transport-level transient failure: connection reset, timeout, heartbeat gap, server outage (5xx). Generally safe to retry with backoff.

Protocol

Protocol-level violation or unclassified WebSocket failure. Indicates an SDK / version mismatch or a server-side bug; retry is unlikely to help.

0.5.1 maps every MarketDataError::WebSocketError to this kind because the variant is currently string-only. 0.6.0 refines the mapping when WebSocketErrorKind lands — IO failures will move to ErrorKind::Network and TLS failures to ErrorKind::Auth.

Auth

Authentication / authorization failure: bad credentials, 401/403, expired token, TLS cert failure. Human intervention required.

RateLimit

Server is rejecting requests because the caller is exceeding its rate budget (HTTP 429). Distinct from ErrorKind::Network — the correct response is to reduce request volume, not to assume the upstream is degraded. Adding parallel retries makes this strictly worse.

Client

Caller-side problem: invalid input, configuration error, client already closed, serialization failure, non-auth/non-throttle 4xx. The SDK can’t recover from the caller’s request without changes from the caller’s side.

Trait Implementations

impl Clone for ErrorKind

fn clone(&self) -> ErrorKind

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ErrorKind

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

Formats the value using the given formatter.

impl Hash for ErrorKind

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 ErrorKind

fn eq(&self, other: &ErrorKind) -> 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 Copy for ErrorKind

impl Eq for ErrorKind

impl StructuralPartialEq for ErrorKind