Struct RequestStateCodec 

pub struct RequestStateCodec { /* private fields */ }

HMAC-SHA256 codec for opaque, expiring MRTR requestState values.

Construct the codec with the same key and TTL on every server instance that may receive a retry. Use encode_for and decode_for when an authenticated subject is available; subject binding prevents one user from replaying another user’s continuation token. Binding is intentionally explicit: authentication middleware may place any application-defined principal type in request extensions, so the transport-neutral codec cannot safely infer one.

Implementations

impl RequestStateCodec

pub fn new( key: impl AsRef<[u8]>, ttl: Duration, ) -> Result<Self, RequestStateError>

Create a codec from a shared key and token TTL.

The key must contain at least 32 bytes of entropy. Configuration secrets should be decoded to raw bytes before calling this constructor.

pub fn with_max_token_bytes(self, max_token_bytes: usize) -> Self

Set the maximum accepted and emitted token size.

pub fn encode<T: Serialize>( &self, state: &T, ) -> Result<String, RequestStateError>

Encode state without authorization-subject binding.

pub fn encode_for<T: Serialize>( &self, subject: impl Into<String>, state: &T, ) -> Result<String, RequestStateError>

Encode state bound to an authenticated subject identifier.

pub fn decode<T: DeserializeOwned>( &self, token: &str, ) -> Result<T, RequestStateError>

Verify and decode state that was not subject-bound.

pub fn decode_for<T: DeserializeOwned>( &self, token: &str, subject: &str, ) -> Result<T, RequestStateError>

Verify and decode state for the current authenticated subject.

Trait Implementations

impl Clone for RequestStateCodec

fn clone(&self) -> RequestStateCodec

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RequestStateCodec

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

Formats the value using the given formatter.