Struct ExchangeTable 

pub struct ExchangeTable { /* private fields */ }

The table of server-initiated requests a session is waiting on.

Cheap to clone: a session’s exchange and the router answering its requests are two handles to one table, never two tables. That matters because a request and the answer completing it must land on the same session, and sharing is what makes that structural rather than a convention.

Implementations

impl ExchangeTable

pub fn new() -> Self

A table with nothing in flight and nothing reading the tail.

The unreadable default is the safe one. A session that has not said it is served as a stream has not established that anything is reading, so the honest answer to “may I ask the peer a question?” is no.

pub fn readable() -> Self

A table whose session’s tail this server drains.

Called once, when a session is opened against a server configured to answer with an event stream. Every later Self::new on the same handle — and there are none, this is the only constructor that sets it — inherits the answer.

pub fn is_readable(&self) -> bool

Whether a server-initiated request can be asked and answered here.

pub fn resolve(&self, id: i64, answer: Answer) -> bool

Hands a peer’s answer to whoever is waiting for id.

false when the id is unknown — a reply to a request that already completed, was refused, or never existed. All three are the same from here and all three are correctly dropped.

pub fn outstanding(&self) -> usize

How many requests are outstanding.

For a diagnostics line and a test. Taking the lock is why this is not on any per-frame path.

Trait Implementations

impl Clone for ExchangeTable

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ExchangeTable

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

Formats the value using the given formatter.

impl Default for ExchangeTable

fn default() -> Self

Returns the “default value” for a type.