Struct Listener 

pub struct Listener { /* private fields */ }

A live LISTEN on the app’s queue channel.

Implementations

impl Listener

pub async fn connect(url: &str, channel: &str) -> Result<Self, QueueError>

Open a dedicated connection and subscribe to channel.

Fails when the database is unreachable right now, which the caller should treat as “run without notifications” rather than as a reason not to start: a subscriber that polls every poll_secs still handles every message, just later.

pub async fn recv(&mut self) -> Result<String, QueueError>

Wait for the next notification and return the topic it names.

The topic is a hint, not an instruction: the caller sweeps for whatever is claimable rather than trusting it, because a notification can be coalesced, arrive twice, or be for a topic whose row another replica has already taken. Treating it as data to act on would make the queue’s correctness depend on the one part of it that is allowed to be lost.