Enum SessionStateError 

#[non_exhaustive]
pub enum SessionStateError {
    SessionNotReady,
    GroupNotFound,
    NotInitialized,
    TransportFailure,
    CryptoFailure,
    SessionDesync,
    Unknown,
}

Stable, machine-readable error classes used for session readiness decisions.

This enum is the single SDK boundary that maps heterogeneous upstream error types into deterministic categories for protocol control flow.

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.

SessionNotReady

Session exists but cannot process application traffic yet.

GroupNotFound

Session/group state does not exist locally.

NotInitialized

MLS stack is not initialized.

TransportFailure

Underlying transport failure.

CryptoFailure

Cryptographic operation failure.

SessionDesync

Session exists but is out of sync with the sender’s epoch (the two sides disagree on the MLS epoch).

What separates this from Self::CryptoFailure is the re-key, not the ACK: under crypto_recovery_enabled both classes withhold the delivery ACK so the sender’s resend can still deliver, but only this one additionally re-establishes the 1:1 session. The split is deliberate — re-keying on an AEAD/authentication failure, which any injected frame can produce, would be a re-key-storm vector.

Unknown

Error that does not match a known class.

Implementations

impl SessionStateError

pub fn code(&self) -> &'static str

Returns a stable, non-localized machine-readable error code.

pub fn classify(error: &Error) -> Self

Classifies protocol-level errors for session state control flow.

pub fn to_welcome_reason_code(&self) -> WelcomeReasonCode

Maps session state class into welcome lifecycle reason taxonomy.

Trait Implementations

impl Clone for SessionStateError

fn clone(&self) -> SessionStateError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for SessionStateError

impl Debug for SessionStateError

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

Formats the value using the given formatter.

impl Eq for SessionStateError

impl From<&MlsError> for SessionStateError

fn from(error: &MlsError) -> Self

Converts to this type from the input type.

impl PartialEq for SessionStateError

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for SessionStateError