feat: allow multiple versions of the same listener

- Change storage from BTreeMap to HashMap<String, Vec<ListenerInfo>>
- Add version tracking to prevent breaking existing connections
- Update start_listener to create new versions instead of stopping existing ones
- Modify stop_listener to handle multiple versions
- Update tests to verify multiple version functionality

Signed-off-by: Eeshu-Yadav <eeshuyadav123@gmail.com>

Author: Eeshu-Yadav

orion-lib/src/listeners/listeners_manager.rs

@@ -15,11 +15,9 @@
 //
 //
 
-use std::collections::BTreeMap;
+use std::collections::HashMap;
 
 use tokio::sync::{broadcast, mpsc};
-#[cfg(debug_assertions)]
-use tracing::debug;
 use tracing::{info, warn};
 
 use orion_configuration::config::{
@@ -49,17 +47,19 @@ pub enum TlsContextChange {
 struct ListenerInfo {
     handle: abort_on_drop::ChildTask<()>,
     listener_conf: ListenerConfig,
+    version: u64,
 }
 impl ListenerInfo {
-    fn new(handle: tokio::task::JoinHandle<()>, listener_conf: ListenerConfig) -> Self {
-        Self { handle: handle.into(), listener_conf }
+    fn new(handle: tokio::task::JoinHandle<()>, listener_conf: ListenerConfig, version: u64) -> Self {
+        Self { handle: handle.into(), listener_conf, version }
     }
 }
 
 pub struct ListenersManager {
     listener_configuration_channel: mpsc::Receiver<ListenerConfigurationChange>,
     route_configuration_channel: mpsc::Receiver<RouteConfigurationChange>,
-    listener_handles: BTreeMap<&'static str, ListenerInfo>,
+    listener_handles: HashMap<String, Vec<ListenerInfo>>,
+    version_counter: u64,
 }
 
 impl ListenersManager {
@@ -70,7 +70,8 @@ impl ListenersManager {
         ListenersManager {
             listener_configuration_channel,
             route_configuration_channel,
-            listener_handles: BTreeMap::new(),
+            listener_handles: HashMap::new(),
+            version_counter: 0,
         }
     }
 
@@ -103,6 +104,7 @@ impl ListenersManager {
                         ListenerConfigurationChange::GetConfiguration(config_dump_tx) => {
                             let listeners: Vec<ListenerConfig> = self.listener_handles
                                 .values()
+                                .flatten()
                                 .map(|info| info.listener_conf.clone())
                                 .collect();
                             config_dump_tx.send(ConfigDump { listeners: Some(listeners), ..Default::default() }).await?;
@@ -125,31 +127,41 @@ impl ListenersManager {
     }
 
     pub fn start_listener(&mut self, listener: Listener, listener_conf: ListenerConfig) -> Result<()> {
-        let listener_name = listener.get_name();
+        let listener_name = listener.get_name().to_string();
         let (addr, dev) = listener.get_socket();
         info!("Listener {} at {addr} (device bind:{})", listener_name, dev.is_some());
-        // spawn the task for this listener address, this will spawn additional task per connection
+
+        self.version_counter += 1;
+        let version = self.version_counter;
+
+        info!("Starting new version {} of listener {}", version, listener_name);
+
+        let listener_name_clone = listener_name.clone();
+
         let join_handle = tokio::spawn(async move {
             let error = listener.start().await;
-            warn!("Listener {listener_name} exited: {error}");
+            warn!("Listener {} version {} exited: {}", listener_name_clone, version, error);
         });
-        #[cfg(debug_assertions)]
-        if self.listener_handles.contains_key(&listener_name) {
-            debug!("Listener {listener_name} already exists, replacing it");
-        }
-        // note: join handle gets overwritten here if it already exists.
-        // handles are abort on drop so will be aborted, closing the socket
-        // but the any tasks spawned within this task, which happens on a per-connection basis,
-        // will survive past this point and only get dropped when their session ends
-        self.listener_handles.insert(listener_name, ListenerInfo::new(join_handle, listener_conf));
+
+        let listener_info = ListenerInfo::new(join_handle, listener_conf, version);
+
+        self.listener_handles.entry(listener_name.clone()).or_insert_with(Vec::new).push(listener_info);
+
+        info!("Listener {} now has {} active version(s)", listener_name, self.listener_handles.get(&listener_name).unwrap().len());
 
         Ok(())
     }
 
     pub fn stop_listener(&mut self, listener_name: &str) -> Result<()> {
-        if let Some(abort_handler) = self.listener_handles.remove(listener_name) {
-            info!("{listener_name} : Stopped");
-            abort_handler.handle.abort();
+        if let Some(listeners) = self.listener_handles.get_mut(listener_name) {
+            info!("Stopping all {} version(s) of listener {}", listeners.len(), listener_name);
+            for listener_info in listeners.drain(..) {
+                info!("Stopping listener {} version {}", listener_name, listener_info.version);
+                listener_info.handle.abort();
+            }
+            self.listener_handles.remove(listener_name);
+        } else {
+            info!("No listeners found with name {}", listener_name);
         }
 
         Ok(())
@@ -202,9 +214,11 @@ mod tests {
         assert!(routeb_tx2.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
         tokio::task::yield_now().await;
 
-        // This should fail because the old listener exited already dropping the rx
-        assert!(routeb_tx1.send(RouteConfigurationChange::Removed("n/a".into())).is_err());
-        // Yield once more just in case more logs can be seen
+        // Both listeners should still be active (multiple versions allowed)
+        assert!(routeb_tx1.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
+        assert!(routeb_tx2.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
+
+        assert_eq!(man.listener_handles.get(name).unwrap().len(), 2);
         tokio::task::yield_now().await;
     }
 
@@ -239,7 +253,7 @@ mod tests {
 
         // See .start_listener() - in the case all channels are dropped the task there
         // should exit with this warning msg
-        let expected = format!("Listener {name} exited: channel closed");
+        let expected = format!("Listener {name} version 1 exited: channel closed");
         logs_assert(|lines: &[&str]| {
             let logs: Vec<_> = lines.iter().filter(|ln| ln.contains(&expected)).collect();
             if logs.len() == 1 {
@@ -249,4 +263,78 @@ mod tests {
             }
         });
     }
+
+    #[traced_test]
+    #[tokio::test]
+    async fn start_multiple_listener_versions() {
+        let chan = 10;
+        let name = "multi-version-listener";
+
+        let (_conf_tx, conf_rx) = mpsc::channel(chan);
+        let (_route_tx, route_rx) = mpsc::channel(chan);
+        let mut man = ListenersManager::new(conf_rx, route_rx);
+
+        let (routeb_tx1, routeb_rx) = broadcast::channel(chan);
+        let (_secb_tx1, secb_rx) = broadcast::channel(chan);
+        let l1 = Listener::test_listener(name, routeb_rx, secb_rx);
+        let l1_info = ListenerConfig {
+            name: name.into(),
+            address: SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 1234),
+            filter_chains: HashMap::default(),
+            bind_device: None,
+            with_tls_inspector: false,
+            proxy_protocol_config: None,
+            with_tlv_listener_filter: false,
+            tlv_listener_filter_config: None,
+        };
+        man.start_listener(l1, l1_info).unwrap();
+        assert!(routeb_tx1.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
+        tokio::task::yield_now().await;
+
+        let (routeb_tx2, routeb_rx) = broadcast::channel(chan);
+        let (_secb_tx2, secb_rx) = broadcast::channel(chan);
+        let l2 = Listener::test_listener(name, routeb_rx, secb_rx);
+        let l2_info = ListenerConfig {
+            name: name.into(),
+            address: SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 1235), // Different port
+            filter_chains: HashMap::default(),
+            bind_device: None,
+            with_tls_inspector: false,
+            proxy_protocol_config: None,
+            with_tlv_listener_filter: false,
+            tlv_listener_filter_config: None,
+        };
+        man.start_listener(l2, l2_info).unwrap();
+        assert!(routeb_tx2.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
+        tokio::task::yield_now().await;
+
+        let (routeb_tx3, routeb_rx) = broadcast::channel(chan);
+        let (_secb_tx3, secb_rx) = broadcast::channel(chan);
+        let l3 = Listener::test_listener(name, routeb_rx, secb_rx);
+        let l3_info = ListenerConfig {
+            name: name.into(),
+            address: SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 1236), // Different port
+            filter_chains: HashMap::default(),
+            bind_device: None,
+            with_tls_inspector: false,
+            proxy_protocol_config: None,
+            with_tlv_listener_filter: false,
+            tlv_listener_filter_config: None,
+        };
+        man.start_listener(l3, l3_info).unwrap();
+        assert!(routeb_tx3.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
+        tokio::task::yield_now().await;
+
+        assert!(routeb_tx1.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
+        assert!(routeb_tx2.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
+        assert!(routeb_tx3.send(RouteConfigurationChange::Removed("n/a".into())).is_ok());
+
+        assert_eq!(man.listener_handles.get(name).unwrap().len(), 3);
+
+        man.stop_listener(name).unwrap();
+
+        assert!(man.listener_handles.get(name).is_none());
+
+        tokio::task::yield_now().await;
+    }
 }