Struct BackendId 

pub struct BackendId {
    pub backend_id: Rc<str>,
    pub address: SocketAddr,
    /* private fields */
}

A backend as the core sees it: the opaque slot, plus the two identity fields the datapath renders.

backend_id and address are copied once, when the session first interns the backend in its BackendRegistry, and every later dial of it clones them from there. Both are immutable for the life of a registry entry, so carrying them is not a cached view of mutable state — no load state crosses this boundary. The mutable half (active_connections, active_requests, failures, connection_time, health, status) stays behind the slot, and the core reaches it only by emitting a BackendDelta.

backend_id is an Rc<str> so that no step past interning copies it: rebuilding Position::Client on Connecting -> Connected once per dial, minting the id for a redial (the registry keeps the Rc<str> it built at interning, #1564), and stamping a request with the backend it runs on, dialled or reused, into HttpContext::backend_id and SessionMetrics::backend_id (#1579) are each a reference-count increment. A String would make every one of them a heap copy.

Fields

backend_id: Rc<str>

Backend::backend_id, for log lines and per-backend metric labels.

address: SocketAddr

Backend::address, for log lines and push_event payloads.

Implementations

impl BackendId

pub fn new(slot: usize, backend_id: Rc<str>, address: SocketAddr) -> Self

An id for the backend at address, named backend_id, in slot of whichever registry mints it (#1684).

The worker’s mux never calls this: its ids come from the session’s BackendRegistry, which interns the backend it names and is the only thing that can resolve a slot back to it. This is for an embedder that owns its own selector — a simulator implementing router::BackendSelector — and numbers its backends itself. A slot means something only to the registry that issued it.

Trait Implementations

impl Clone for BackendId

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 BackendId

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

Formats the value using the given formatter.

impl Eq for BackendId

impl PartialEq for BackendId

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for BackendId