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#[cfg(test)]
mod notifier_test {
use crate::{closable_trait::ClosableMessage, notifier::NotifierHub};
use std::sync::Arc;
use tokio::sync::Mutex;
// This type is going to be sent among the subscribers
#[derive(Clone, Debug)]
enum Message {
StringMessage(String),
Number(u32),
Close,
}
impl ClosableMessage for Message {
fn get_close_message() -> Self {
Self::Close
}
}
// First subscriber
fn subscriber_1(hub: Arc<Mutex<NotifierHub<Message, &'static str>>>) {
tokio::spawn(async move {
// Subscribing to "channel1" and "channel2"
let mut receiver = hub
.lock()
.await
.subscribe_multiple(&["channel1", "channel2"], 100);
loop {
let msg = receiver.recv().await.unwrap();
match msg {
Message::StringMessage(s_msg) => {
println!("Just received a new message as subscriber_1: {s_msg}")
}
Message::Number(n) => println!("Just received a number as subscriber_1: {n}"),
Message::Close => break,
}
}
// As we are breaking with close, we don't need to unsubscribe
});
}
// Second subscriber
fn subscriber_2(hub: Arc<Mutex<NotifierHub<Message, &'static str>>>) {
tokio::spawn(async move {
// Subscribing only to "channel1"
let mut receiver = hub.lock().await.subscribe(&"channel1", 100);
loop {
let msg = receiver.recv().await.unwrap();
match msg {
Message::StringMessage(s_msg) => {
println!("Just received a new message as subscriber_2: {s_msg}")
}
Message::Number(n) => println!("Just received a number as subscriber_2: {n}"),
Message::Close => break,
}
}
// As we are breaking with close, we don't need to unsubscribe
});
}
#[tokio::test]
async fn test_main() {
// Create a new NotifierHub wrapped in a mutex
let hub = Arc::new(Mutex::new(NotifierHub::new()));
let mut creation_waiter = hub.lock().await.get_creation_waiter(&"channel1");
let mut destruction_waiter = hub.lock().await.get_destruction_waiter(&"channel1");
// Start subscriber threads
subscriber_1(hub.clone());
subscriber_2(hub.clone());
// Wait for subscriber_1 and subscriber_2 to be ready to receive messages on "channel1"
creation_waiter.recv().await.unwrap();
creation_waiter.recv().await.unwrap();
{
let mut hub = hub.lock().await;
let msg1 = Message::StringMessage("Hello!".to_string());
// Send the message to subscriber_1 and subscriber_2 as they are both subscribed to "channel1"
hub.clone_send(msg1, &"channel1").unwrap();
let msg2 = Message::Number(18);
// Only subscriber_1 will receive this message as it is subscribed to "channel2"
hub.clone_send(msg2, &"channel2").unwrap();
let msg3 = Message::StringMessage("Broadcast message!".to_string());
// Sends msg3 on all channels, so subscriber_1 will receive it twice
hub.broadcast_clone(msg3);
// Send a close message to subscriber_1 and subscriber_2
hub.shutdown_clone(&"channel1").unwrap();
}
// Wait for both subscriber_1 and subscriber_2 to unsubscribe
destruction_waiter.recv().await;
destruction_waiter.recv().await;
}
}