Struct ConnectionPool 

pub struct ConnectionPool { /* private fields */ }

Per-peer connection pool with idle eviction and capacity enforcement.

The pool stores connections grouped by peer_id. On acquire it first looks for an existing idle connection; if none is available it creates a new Connecting slot, subject to both per-peer and global limits.

Implementations

impl ConnectionPool

pub fn new(config: PoolConfig) -> Self

Create a new pool with the given configuration.

pub fn with_defaults() -> Self

Create a new pool with default configuration.

pub fn acquire(&self, peer_id: &str) -> Result<u64, PoolError>

Acquire a connection to peer_id.

1. If an idle connection exists for the peer it is transitioned to Connecting and its ID is returned.
2. Otherwise a new slot in Connecting state is created, provided neither the per-peer limit nor the global limit would be exceeded.

Errors

• PoolError::PeerCapacityExceeded when the per-peer limit is reached.
• PoolError::GlobalCapacityExceeded when the global limit is reached.

pub fn mark_active(&self, connection_id: u64) -> Result<(), PoolError>

Transition connection_id to Active.

Errors

Returns PoolError::ConnectionNotFound if no connection with the given ID exists.

pub fn mark_idle(&self, connection_id: u64) -> Result<(), PoolError>

Transition connection_id to Idle.

Errors

Returns PoolError::ConnectionNotFound if no connection with the given ID exists.

pub fn mark_failed( &self, connection_id: u64, reason: &str, ) -> Result<(), PoolError>

Transition connection_id to Failed with the supplied human-readable reason.

Errors

Returns PoolError::ConnectionNotFound if no connection with the given ID exists.

pub fn release(&self, connection_id: u64)

Remove connection_id from the pool entirely.

This is a no-op when the connection does not exist. Empty peer buckets are cleaned up automatically.

pub fn evict_idle(&self, now: Instant) -> usize

Remove all connections that have been idle longer than PoolConfig::idle_timeout, measured against now.

Returns the number of connections evicted.

pub fn connection_count(&self) -> usize

Total number of connections currently in the pool (all states).

pub fn idle_count(&self) -> usize

Number of connections in the Idle state.

pub fn active_count(&self) -> usize

Number of connections in the Active state.

pub fn stats(&self) -> PoolStatsSnapshot

Return an immutable snapshot of the pool-wide statistics.