Struct OutboundPool 

pub struct OutboundPool { /* private fields */ }

Bounded pool of idle outbound SMTP connections.

Thread safety

OutboundPool is Send + Sync; share it via Arc<OutboundPool>.

Implementations

impl OutboundPool

pub fn new(config: OutboundPoolConfig, shutdown_rx: Receiver<bool>) -> Arc<Self>

Create a new pool and spawn the background idle-reaper task.

The reaper stops automatically when shutdown_rx yields true.

pub async fn get_or_connect(&self, remote_key: &str) -> Result<PooledConn>

Obtain a connection to remote_key (format: "host:port").

If a pooled idle connection is available, returns it immediately. Otherwise opens a new TCP connection, reads the 220 greeting, sends EHLO localhost, reads the response, and wraps everything in a PooledConn.

pub async fn return_conn(&self, conn: PooledConn)

Return a connection to the pool after use.

Sends RSET\r\n and waits for a 250 response. On any I/O or protocol error the connection is silently dropped. If the pool would exceed its caps the connection is also dropped.

pub fn idle_count(&self) -> usize

Count currently idle connections (for testing / metrics).