Struct PgListener 

pub struct PgListener { /* private fields */ }

A connection dedicated to LISTEN/NOTIFY, plus ordinary query execution on the same connection — mirroring how pylon.worker.IndexWorker and pylon.cache.CacheInvalidationWorker both listen and run queries (claim/mark-done/mark-failed, cache eviction) on the one connection they’re constructed with today.

Implementations

impl PgListener

pub async fn connect<F>(dsn: &str, on_notification: F) -> Result<Self>

where F: Fn(Notification) + Send + 'static,

Opens a new, non-pooled connection and spawns a background task that drives it for the lifetime of the returned PgListener, calling on_notification once per NOTIFY received (on any channel — listen/unlisten control which channels the server actually sends). The task exits when the connection is closed or errors, which happens when the returned PgListener (and its Client) is dropped.

pub fn types(&self) -> Arc<ExtensionOids>

The type OIDs currently discovered for this database — see PgPool::types.

pub async fn refresh_types(&self) -> Result<()>

Re-runs type discovery on this listener’s own connection — see PgPool::refresh_types. Nothing to invalidate alongside it: this connection is unpooled and prepares each statement afresh.

pub async fn listen(&self, channel: &str) -> Result<()>

pub async fn unlisten(&self, channel: &str) -> Result<()>

pub async fn query_typed( &self, sql: &str, params: &[DecodedValue], ext: &ExtensionOids, ) -> Result<Vec<DecodedValue>>

pub async fn query_typed_named( &self, sql: &str, params: &[DecodedValue], ext: &ExtensionOids, ) -> Result<Vec<DecodedValue>>

Like query_typed, but decodes every column of every row by name (DecodedValue::Object) instead of assuming column 0 is the whole result — for hand-written queries with several named columns a caller accesses by name.

pub async fn batch_execute(&self, sql: &str) -> Result<()>

Runs sql via the simple query protocol — no bind parameters, but able to run several ;-separated statements in one call, matching PgPool::batch_execute. Used for bootstrap DDL on this connection.

pub async fn execute_typed( &self, sql: &str, params: &[DecodedValue], ) -> Result<u64>