Struct PgmqNotifyListener 

pub struct PgmqNotifyListener { /* private fields */ }

PGMQ notification listener using PostgreSQL LISTEN/NOTIFY

Implementations

impl PgmqNotifyListener

pub async fn new( pool: PgPool, config: PgmqNotifyConfig, buffer_size: usize, ) -> Result<Self>

Create a new PGMQ notification listener

Arguments

• pool - PostgreSQL connection pool
• config - PGMQ notification configuration
• buffer_size - MPSC channel buffer size (TAS-51: bounded channels)

Returns

• Result<Self> - Configured listener or error

Note

TAS-51: Migrated from unbounded to bounded channel to prevent OOM during notification bursts. Buffer size should come from:

• Orchestration: config.mpsc_channels.orchestration.event_listeners.pgmq_event_buffer_size
• Worker: config.mpsc_channels.worker.event_listeners.pgmq_event_buffer_size

pub fn config(&self) -> &PgmqNotifyConfig

Get the configuration

pub fn stats(&self) -> ListenerStats

Get listener statistics

pub async fn connect(&mut self) -> Result<()>

Connect to the database for listening

pub async fn disconnect(&mut self) -> Result<()>

Disconnect from the database

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

Listen to a specific channel

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

Stop listening to a specific channel

pub async fn listen_queue_created(&mut self) -> Result<()>

Listen to queue created events

pub async fn listen_message_ready_for_namespace( &mut self, namespace: &str, ) -> Result<()>

Listen to message ready events for a specific namespace

pub async fn listen_message_ready_global(&mut self) -> Result<()>

Listen to all message ready events (global)

pub async fn listen_default_namespaces(&mut self) -> Result<()>

Listen to default namespaces from configuration

pub async fn next_event(&mut self) -> Result<Option<PgmqNotifyEvent>>

Get the next notification event (blocking)

pub async fn listen_with_handler<H>(&mut self, handler: H) -> Result<()>

where H: PgmqEventHandler + 'static,

Start listening loop with an event handler

This function now RUNS THE LOOP IN THE CURRENT TASK and only returns when the underlying notification stream ends or an error occurs. If you want a detached background task, use start_listening_with_handler (see below).

pub async fn start_listening_with_handler<H>( &mut self, handler: H, ) -> Result<JoinHandle<Result<()>>>

where H: PgmqEventHandler + 'static,

Start listening loop with an event handler in a detached background task

This spawns the listener in the background and returns immediately. For applications that need the listener to block until completion, use listen_with_handler instead.

pub async fn start_listening(&mut self) -> Result<()>

Start a simple listening loop that queues events (detached background task)

pub async fn is_healthy(&self) -> bool

Check if the listener is healthy

pub fn listening_channels(&self) -> Vec<String>

Get list of channels currently being listened to

Trait Implementations

impl Debug for PgmqNotifyListener

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

Formats the value using the given formatter.