Struct Subscriber

pub struct Subscriber<T: Hash + Eq, M> { /* private fields */ }

Subscriber to the tagged queue created by subscribe() function.

Implementations

impl<T, M> Subscriber<T, M>

where T: Hash + Eq,

pub fn subs_count(&self) -> usize

Returns the number of subscribers of the same tag.

pub fn len(&self) -> usize

Returns length of tagged queue.

Example

use mqb::MessageQueueBroker;

let mqb = MessageQueueBroker::unbounded();
let sub1 = mqb.subscribe(1);
let sub2 = mqb.subscribe(2);

mqb.send(&2, 1).await.unwrap();
assert_eq!(sub1.len(), 0);
assert_eq!(sub2.len(), mqb.len());

pub fn is_empty(&self) -> bool

Checks if the tagged queue is empty.

Example

use mqb::MessageQueueBroker;

let mqb = MessageQueueBroker::unbounded();
let sub1 = mqb.subscribe(1);
let sub2 = mqb.subscribe(2);

mqb.send(&2, 1).await.unwrap();
assert!(sub1.is_empty());
assert_eq!(sub2.len(), mqb.len());

pub fn is_closed(&self) -> bool

Checks if the broker is closed.

pub fn try_recv(&self) -> Result<M, TryRecvError>

Trying to receive a message from the tagged queue.

If broker is closed then returns TryRecvError::Closed. If the tagged queue is empty returns TryRecvError::Empty.

Ok

use mqb::MessageQueueBroker;

let mqb = MessageQueueBroker::unbounded();
let sub = mqb.subscribe(1);

assert!(mqb.try_send(&1, 1).is_ok());
assert_eq!(sub.try_recv().unwrap(), 1);

Broker closed

use mqb::{MessageQueueBroker, TryRecvError};

let mqb = MessageQueueBroker::<i32, i32>::unbounded();
let sub = mqb.subscribe(1);

mqb.close();
assert_eq!(sub.try_recv().unwrap_err(), TryRecvError::Closed);

Queue is empty

use mqb::{MessageQueueBroker, TryRecvError};

let mqb = MessageQueueBroker::<i32, i32>::unbounded();
let sub = mqb.subscribe(1);

assert_eq!(sub.try_recv().unwrap_err(), TryRecvError::Empty);

pub async fn recv(&self) -> Result<M, RecvError>

Receives a message from the tagged queue.

If broker is closed then returns RecvError.

Ok

use mqb::MessageQueueBroker;

let mqb = MessageQueueBroker::unbounded();
let sub = mqb.subscribe(1);

assert!(mqb.send(&1, 1).await.is_ok());
assert_eq!(sub.recv().await.unwrap(), 1);

Broker closed

use mqb::{MessageQueueBroker, RecvError};

let mqb = MessageQueueBroker::<i32, i32>::unbounded();
let sub = mqb.subscribe(1);

mqb.close();
assert_eq!(sub.recv().await.unwrap_err(), RecvError);

Queue is empty

use mqb::MessageQueueBroker;

let mqb = MessageQueueBroker::<i32, i32>::bounded(1);
let sub = mqb.subscribe(1);

// Wait endlessly...
sub.recv().await;

Trait Implementations

impl<T, M> Clone for Subscriber<T, M>

where T: Hash + Eq + Clone,

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug + Hash + Eq, M: Debug> Debug for Subscriber<T, M>

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

Formats the value using the given formatter.

impl<T, M> Drop for Subscriber<T, M>

where T: Hash + Eq,

fn drop(&mut self)

Executes the destructor for this type.