Struct BackendGroup 

pub struct BackendGroup {
    pub backends: Vec<Arc<Backend>>,
    pub strategy: LbStrategy,
    /* private fields */
}

A set of backends for a single service, with a configured selection strategy.

Fields

backends: Vec<Arc<Backend>>

The backends in this group.

strategy: LbStrategy

The strategy used by select.

Implementations

impl BackendGroup

pub fn new(strategy: LbStrategy) -> Self

Create an empty group with the given strategy.

pub fn select(&self) -> Option<Arc<Backend>>

Select a healthy backend using the configured strategy.

Returns None if every backend is unhealthy (or the group is empty).

pub fn update_backends(&mut self, addrs: Vec<SocketAddr>)

Replace the backend list while preserving state for addresses that remain unchanged.

Backends whose address appears in addrs keep their existing connection counts, health status, and failure counters. New addresses get a fresh Backend. Addresses no longer in addrs are dropped.

pub fn add_backend(&mut self, addr: SocketAddr)

Add a backend if its address is not already present.

pub fn remove_backend(&mut self, addr: &SocketAddr)

Remove the backend with the given address, if present.