Struct Subscriber

pub struct Subscriber { /* private fields */ }

Retrieves messages from given subscription created by Client::subscribe.

Implements futures::stream::Stream for ergonomic async message processing.

Examples

let mut nc = async_nats::connect("demo.nats.io").await?;

Implementations

impl Subscriber

pub async fn unsubscribe(&mut self) -> Result<(), UnsubscribeError>

Unsubscribes from subscription, draining all remaining messages.

Examples

let client = async_nats::connect("demo.nats.io").await?;

let mut subscriber = client.subscribe("foo").await?;

subscriber.unsubscribe().await?;

pub async fn unsubscribe_after( &mut self, unsub_after: u64, ) -> Result<(), UnsubscribeError>

Unsubscribes from subscription after reaching given number of messages. This is the total number of messages received by this subscription in it’s whole lifespan. If it already reached or surpassed the passed value, it will immediately stop.

Examples

let client = async_nats::connect("demo.nats.io").await?;

let mut subscriber = client.subscribe("test").await?;
subscriber.unsubscribe_after(3).await?;

for _ in 0..3 {
    client.publish("test", "data".into()).await?;
}

while let Some(message) = subscriber.next().await {
    println!("message received: {:?}", message);
}
println!("no more messages, unsubscribed");

Trait Implementations

impl Debug for Subscriber

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

Formats the value using the given formatter.

impl Drop for Subscriber

fn drop(&mut self)

Executes the destructor for this type.

impl Stream for Subscriber

type Item = Message

Values yielded by the stream.

fn poll_next( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Option<Self::Item>>

Attempt to pull out the next value of this stream, registering the current task for wakeup if the value is not yet available, and returning None if the stream is exhausted.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the stream.