1 files changed, 309 insertions, 0 deletions
diff --git a/p2p/examples/monitor/src/service.rs b/p2p/examples/monitor/src/service.rs
new file mode 100644
index 0000000..15ce8da
--- /dev/null
+++ b/p2p/examples/monitor/src/service.rs
@@ -0,0 +1,309 @@
+use std::{collections::HashMap, sync::Arc};
+
+use futures::stream::{FuturesUnordered, StreamExt};
+use log::{debug, error};
+use ringbuffer::{AllocRingBuffer, RingBuffer};
+use serde::{Deserialize, Serialize};
+use smol::{lock::Mutex, Executor};
+
+use karyon_core::async_util::{TaskGroup, TaskResult};
+use karyon_jsonrpc::{message::SubscriptionID, rpc_impl, rpc_pubsub_impl, Channel, Subscription};
+use karyon_p2p::{monitor::MonitorTopic, ArcBackend, Result};
+
+const EVENT_BUFFER_SIZE: usize = 60;
+
+pub struct MonitorRPC {
+    backend: ArcBackend,
+    subs: Arc<Subscriptions>,
+    task_group: TaskGroup,
+}
+
+impl MonitorRPC {
+    pub fn new(backend: ArcBackend, ex: Arc<Executor<'static>>) -> Arc<Self> {
+        Arc::new(MonitorRPC {
+            backend,
+            task_group: TaskGroup::with_executor(ex.clone().into()),
+            subs: Subscriptions::new(ex),
+        })
+    }
+
+    pub async fn run(self: &Arc<Self>) -> Result<()> {
+        let conn_events = self.backend.monitor().conn_events().await;
+        let peer_pool_events = self.backend.monitor().peer_pool_events().await;
+        let discovery_events = self.backend.monitor().discovery_events().await;
+
+        let on_failuer = |res: TaskResult<Result<()>>| async move {
+            if let TaskResult::Completed(Err(err)) = res {
+                error!("Event receive loop: {err}")
+            }
+        };
+
+        let selfc = self.clone();
+        self.task_group.spawn(
+            async move {
+                loop {
+                    let event = conn_events.recv().await?;
+                    selfc.subs.notify(MonitorTopic::Conn, event).await;
+                }
+            },
+            on_failuer,
+        );
+
+        let selfc = self.clone();
+        self.task_group.spawn(
+            async move {
+                loop {
+                    let event = peer_pool_events.recv().await?;
+                    selfc.subs.notify(MonitorTopic::PeerPool, event).await;
+                }
+            },
+            on_failuer,
+        );
+
+        let selfc = self.clone();
+        self.task_group.spawn(
+            async move {
+                loop {
+                    let event = discovery_events.recv().await?;
+                    selfc.subs.notify(MonitorTopic::Discovery, event).await;
+                }
+            },
+            on_failuer,
+        );
+
+        Ok(())
+    }
+
+    pub async fn shutdown(&self) {
+        self.task_group.cancel().await;
+        self.subs.stop().await;
+    }
+}
+
+#[rpc_impl]
+impl MonitorRPC {
+    pub async fn ping(
+        &self,
+        _params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        Ok(serde_json::json!(Pong {}))
+    }
+
+    pub async fn peer_id(
+        &self,
+        _params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        Ok(serde_json::json!(self.backend.peer_id().to_string()))
+    }
+
+    pub async fn inbound_connection(
+        &self,
+        _params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        Ok(serde_json::json!(self.backend.inbound_slots()))
+    }
+
+    pub async fn outbound_connection(
+        &self,
+        _params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        Ok(serde_json::json!(self.backend.outbound_slots()))
+    }
+}
+
+#[rpc_pubsub_impl]
+impl MonitorRPC {
+    pub async fn conn_subscribe(
+        &self,
+        chan: Arc<Channel>,
+        method: String,
+        _params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        let sub = chan.new_subscription(&method).await;
+        let sub_id = sub.id;
+
+        self.subs.add(MonitorTopic::Conn, sub).await;
+
+        Ok(serde_json::json!(sub_id))
+    }
+
+    pub async fn peer_pool_subscribe(
+        &self,
+        chan: Arc<Channel>,
+        method: String,
+        _params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        let sub = chan.new_subscription(&method).await;
+        let sub_id = sub.id;
+
+        self.subs.add(MonitorTopic::PeerPool, sub).await;
+
+        Ok(serde_json::json!(sub_id))
+    }
+
+    pub async fn discovery_subscribe(
+        &self,
+        chan: Arc<Channel>,
+        method: String,
+        _params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        let sub = chan.new_subscription(&method).await;
+        let sub_id = sub.id;
+
+        self.subs.add(MonitorTopic::Discovery, sub).await;
+
+        Ok(serde_json::json!(sub_id))
+    }
+
+    pub async fn conn_unsubscribe(
+        &self,
+        chan: Arc<Channel>,
+        _method: String,
+        params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        let sub_id: SubscriptionID = serde_json::from_value(params)?;
+        chan.remove_subscription(&sub_id).await;
+        Ok(serde_json::json!(true))
+    }
+
+    pub async fn peer_pool_unsubscribe(
+        &self,
+        chan: Arc<Channel>,
+        _method: String,
+        params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        let sub_id: SubscriptionID = serde_json::from_value(params)?;
+        chan.remove_subscription(&sub_id).await;
+        Ok(serde_json::json!(true))
+    }
+
+    pub async fn discovery_unsubscribe(
+        &self,
+        chan: Arc<Channel>,
+        _method: String,
+        params: serde_json::Value,
+    ) -> karyon_jsonrpc::Result<serde_json::Value> {
+        let sub_id: SubscriptionID = serde_json::from_value(params)?;
+        chan.remove_subscription(&sub_id).await;
+        Ok(serde_json::json!(true))
+    }
+}
+
+#[derive(Deserialize, Serialize)]
+struct Pong {}
+
+struct Subscriptions {
+    subs: Mutex<HashMap<MonitorTopic, HashMap<SubscriptionID, Subscription>>>,
+    buffer: Mutex<HashMap<MonitorTopic, AllocRingBuffer<serde_json::Value>>>,
+    task_group: TaskGroup,
+}
+
+impl Subscriptions {
+    fn new(ex: Arc<Executor<'static>>) -> Arc<Self> {
+        let mut subs = HashMap::new();
+        subs.insert(MonitorTopic::Conn, HashMap::new());
+        subs.insert(MonitorTopic::PeerPool, HashMap::new());
+        subs.insert(MonitorTopic::Discovery, HashMap::new());
+
+        let mut buffer = HashMap::new();
+        buffer.insert(MonitorTopic::Conn, AllocRingBuffer::new(EVENT_BUFFER_SIZE));
+        buffer.insert(
+            MonitorTopic::PeerPool,
+            AllocRingBuffer::new(EVENT_BUFFER_SIZE),
+        );
+        buffer.insert(
+            MonitorTopic::Discovery,
+            AllocRingBuffer::new(EVENT_BUFFER_SIZE),
+        );
+
+        Arc::new(Self {
+            subs: Mutex::new(subs),
+            buffer: Mutex::new(buffer),
+            task_group: TaskGroup::with_executor(ex.into()),
+        })
+    }
+
+    /// Adds the subscription to the subs map according to the given type
+    async fn add(self: &Arc<Self>, ty: MonitorTopic, sub: Subscription) {
+        match self.subs.lock().await.get_mut(&ty) {
+            Some(subs) => {
+                subs.insert(sub.id, sub.clone());
+            }
+            None => todo!(),
+        }
+        // Send old events in the buffer to the subscriber
+        self.send_old_events(ty, sub).await;
+    }
+
+    /// Notifies all subscribers   
+    async fn notify<T: Serialize>(&self, ty: MonitorTopic, event: T) {
+        let event = serde_json::json!(event);
+        // Add the new event to the ringbuffer
+        match self.buffer.lock().await.get_mut(&ty) {
+            Some(events) => events.push(event.clone()),
+            None => todo!(),
+        }
+
+        // Notify the subscribers
+        match self.subs.lock().await.get_mut(&ty) {
+            Some(subs) => {
+                let mut fulist = FuturesUnordered::new();
+
+                for sub in subs.values() {
+                    let fu = async { (sub.id, sub.notify(event.clone()).await) };
+                    fulist.push(fu)
+                }
+
+                let mut cleanup_list = vec![];
+                while let Some((sub_id, result)) = fulist.next().await {
+                    if let Err(err) = result {
+                        error!("Failed to notify the subscription: {:?} {sub_id} {err}", ty);
+                        cleanup_list.push(sub_id);
+                    }
+                }
+                drop(fulist);
+
+                for sub_id in cleanup_list {
+                    subs.remove(&sub_id);
+                }
+            }
+            None => todo!(),
+        }
+    }
+
+    /// Sends old events in the ringbuffer to the new subscriber.
+    async fn send_old_events(self: &Arc<Self>, ty: MonitorTopic, sub: Subscription) {
+        let ty_cloned = ty.clone();
+        let sub_id = sub.id;
+        let on_complete = move |res: TaskResult<()>| async move {
+            debug!("Send old events: {:?} {:?} {res}", ty_cloned, sub_id);
+        };
+
+        let selfc = self.clone();
+        self.task_group.spawn(
+            async move {
+                match selfc.buffer.lock().await.get_mut(&ty) {
+                    Some(events) => {
+                        let mut fu = FuturesUnordered::new();
+
+                        for event in events.iter().rev() {
+                            fu.push(sub.notify(event.clone()))
+                        }
+
+                        while let Some(result) = fu.next().await {
+                            if result.is_err() {
+                                return;
+                            }
+                        }
+                    }
+                    None => todo!(),
+                }
+            },
+            on_complete,
+        );
+    }
+
+    async fn stop(&self) {
+        self.task_group.cancel().await;
+    }
+}