player shutdown API (#58)

Reviewed-on: lavina/lavina#58

crates/lavina-core/src/player.rs

@@ -55,7 +55,7 @@ pub struct ConnectionId(pub AnonKey);
 /// The connection is used to send commands to the player actor and to receive updates that might be sent to the client.
 pub struct PlayerConnection {
     pub connection_id: ConnectionId,
-    pub receiver: Receiver<Updates>,
+    pub receiver: Receiver<ConnectionMessage>,
     player_handle: PlayerHandle,
 }
 impl PlayerConnection {
@@ -160,7 +160,7 @@ impl PlayerHandle {
 enum ActorCommand {
     /// Establish a new connection.
     AddConnection {
-        sender: Sender<Updates>,
+        sender: Sender<ConnectionMessage>,
         promise: Promise<ConnectionId>,
     },
     /// Terminate an existing connection.
@@ -276,11 +276,27 @@ impl PlayerRegistry {
         Ok(())
     }
 
+    #[tracing::instrument(skip(self), name = "PlayerRegistry::get_player")]
     pub async fn get_player(&self, id: &PlayerId) -> Option<PlayerHandle> {
         let inner = self.0.read().await;
         inner.players.get(id).map(|(handle, _)| handle.clone())
     }
 
+    #[tracing::instrument(skip(self), name = "PlayerRegistry::stop_player")]
+    pub async fn stop_player(&self, id: &PlayerId) -> Result<Option<()>> {
+        let mut inner = self.0.write().await;
+        if let Some((handle, fiber)) = inner.players.remove(id) {
+            handle.send(ActorCommand::Stop).await;
+            drop(handle);
+            fiber.await?;
+            inner.metric_active_players.dec();
+            Ok(Some(()))
+        } else {
+            Ok(None)
+        }
+    }
+
+    #[tracing::instrument(skip(self), name = "PlayerRegistry::get_or_launch_player")]
     pub async fn get_or_launch_player(&mut self, id: &PlayerId) -> PlayerHandle {
         let inner = self.0.read().await;
         if let Some((handle, _)) = inner.players.get(id) {
@@ -305,6 +321,7 @@ impl PlayerRegistry {
         }
     }
 
+    #[tracing::instrument(skip(self), name = "PlayerRegistry::connect_to_player")]
     pub async fn connect_to_player(&mut self, id: &PlayerId) -> PlayerConnection {
         let player_handle = self.get_or_launch_player(id).await;
         player_handle.subscribe().await
@@ -337,7 +354,7 @@ struct PlayerRegistryInner {
 struct Player {
     player_id: PlayerId,
     storage_id: u32,
-    connections: AnonTable<Sender<Updates>>,
+    connections: AnonTable<Sender<ConnectionMessage>>,
     my_rooms: HashMap<RoomId, RoomHandle>,
     banned_from: HashSet<RoomId>,
     rx: Receiver<(ActorCommand, Span)>,
@@ -438,7 +455,7 @@ impl Player {
             _ => {}
         }
         for (_, connection) in &self.connections {
-            let _ = connection.send(update.clone()).await;
+            let _ = connection.send(ConnectionMessage::Update(update.clone())).await;
         }
     }
 
@@ -589,7 +606,18 @@ impl Player {
             if ConnectionId(a) == except {
                 continue;
             }
-            let _ = b.send(update.clone()).await;
+            let _ = b.send(ConnectionMessage::Update(update.clone())).await;
         }
     }
 }
+
+pub enum ConnectionMessage {
+    Update(Updates),
+    Stop(StopReason),
+}
+
+#[derive(Debug)]
+pub enum StopReason {
+    ServerShutdown,
+    InternalError,
+}

crates/mgmt-api/src/lib.rs

@@ -11,6 +11,11 @@ pub struct CreatePlayerRequest<'a> {
     pub name: &'a str,
 }
 
+#[derive(Serialize, Deserialize)]
+pub struct StopPlayerRequest<'a> {
+    pub name: &'a str,
+}
+
 #[derive(Serialize, Deserialize)]
 pub struct ChangePasswordRequest<'a> {
     pub player_name: &'a str,
@@ -19,6 +24,7 @@ pub struct ChangePasswordRequest<'a> {
 
 pub mod paths {
     pub const CREATE_PLAYER: &'static str = "/mgmt/create_player";
+    pub const STOP_PLAYER: &'static str = "/mgmt/stop_player";
     pub const SET_PASSWORD: &'static str = "/mgmt/set_password";
 }
 

crates/projection-irc/src/lib.rs

@@ -507,15 +507,22 @@ async fn handle_registered_socket<'a>(
                 buffer.clear();
             },
             update = connection.receiver.recv() => {
-                if let Some(update) = update {
+                match update {
+                    Some(ConnectionMessage::Update(update)) => {
                         handle_update(&config, &user, &player_id, writer, &rooms, update).await?;
-                } else {
+                    }
+                    Some(ConnectionMessage::Stop(_)) => {
+                        tracing::debug!("Connection is being terminated");
+                        break;
+                    }
+                    None => {
                         log::warn!("Player is terminated, must terminate the connection");
                         break;
                     }
                 }
             }
         }
+    }
     ServerMessage {
         tags: vec![],
         sender: Some(config.server_name.clone()),

crates/projection-xmpp/src/lib.rs

@@ -23,7 +23,7 @@ use tokio_rustls::rustls::{Certificate, PrivateKey};
 use tokio_rustls::TlsAcceptor;
 
 use lavina_core::auth::{Authenticator, Verdict};
-use lavina_core::player::{PlayerConnection, PlayerId, PlayerRegistry};
+use lavina_core::player::{ConnectionMessage, PlayerConnection, PlayerId, PlayerRegistry, StopReason};
 use lavina_core::prelude::*;
 use lavina_core::repo::Storage;
 use lavina_core::room::RoomRegistry;
@@ -31,6 +31,7 @@ use lavina_core::terminator::Terminator;
 use lavina_core::LavinaCore;
 use proto_xmpp::bind::{Name, Resource};
 use proto_xmpp::stream::*;
+use proto_xmpp::streamerror::{StreamError, StreamErrorKind};
 use proto_xmpp::xml::{Continuation, FromXml, Parser, ToXml};
 use sasl::AuthBody;
 
@@ -395,17 +396,42 @@ async fn socket_final(
                 true
             },
             update = conn.user_handle.receiver.recv() => {
-                if let Some(update) = update {
+                match update {
+                    Some(ConnectionMessage::Update(update)) => {
                         conn.handle_update(&mut events, update).await?;
                         for i in &events {
                             xml_writer.write_event_async(i).await?;
                         }
                         events.clear();
                         xml_writer.get_mut().flush().await?;
-                } else {
+                    }
-                    log::warn!("Player is terminated, must terminate the connection");
+                    Some(ConnectionMessage::Stop(reason)) => {
+                        tracing::debug!("Connection is being terminated: {reason:?}");
+                        let kind = match reason {
+                            StopReason::ServerShutdown => StreamErrorKind::SystemShutdown,
+                            StopReason::InternalError => StreamErrorKind::InternalServerError,
+                        };
+                        StreamError { kind }.serialize(&mut events);
+                        ServerStreamEnd.serialize(&mut events);
+                        for i in &events {
+                            xml_writer.write_event_async(i).await?;
+                        }
+                        events.clear();
+                        xml_writer.get_mut().flush().await?;
                         break;
                     }
+                    None => {
+                        log::error!("Player is terminated, must terminate the connection");
+                        StreamError { kind: StreamErrorKind::SystemShutdown }.serialize(&mut events);
+                        ServerStreamEnd.serialize(&mut events);
+                        for i in &events {
+                            xml_writer.write_event_async(i).await?;
+                        }
+                        events.clear();
+                        xml_writer.get_mut().flush().await?;
+                        break;
+                    }
+                }
                 false
             }
 

crates/proto-xmpp/src/lib.rs

@@ -10,6 +10,7 @@ pub mod sasl;
 pub mod session;
 pub mod stanzaerror;
 pub mod stream;
+pub mod streamerror;
 pub mod tls;
 pub mod xml;
 

crates/proto-xmpp/src/streamerror.rs

@@ -0,0 +1,41 @@
+use crate::xml::ToXml;
+use quick_xml::events::{BytesEnd, BytesStart, Event};
+
+/// Stream error condition
+///
+/// [Spec](https://xmpp.org/rfcs/rfc6120.html#streams-error-conditions).
+pub enum StreamErrorKind {
+    /// The server has experienced a misconfiguration or other internal error that prevents it from servicing the stream.
+    InternalServerError,
+    /// The server is being shut down and all active streams are being closed.
+    SystemShutdown,
+}
+impl StreamErrorKind {
+    pub fn from_str(s: &str) -> Option<Self> {
+        match s {
+            "internal-server-error" => Some(Self::InternalServerError),
+            "system-shutdown" => Some(Self::SystemShutdown),
+            _ => None,
+        }
+    }
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            Self::InternalServerError => "internal-server-error",
+            Self::SystemShutdown => "system-shutdown",
+        }
+    }
+}
+
+pub struct StreamError {
+    pub kind: StreamErrorKind,
+}
+impl ToXml for StreamError {
+    fn serialize(&self, events: &mut Vec<Event<'static>>) {
+        events.push(Event::Start(BytesStart::new("stream:error")));
+        events.push(Event::Empty(BytesStart::new(format!(
+            r#"{} xmlns="urn:ietf:params:xml:ns:xmpp-streams""#,
+            self.kind.as_str()
+        ))));
+        events.push(Event::End(BytesEnd::new("stream:error")));
+    }
+}

src/http.rs

@@ -13,6 +13,7 @@ use serde::{Deserialize, Serialize};
 use tokio::net::TcpListener;
 
 use lavina_core::auth::{Authenticator, UpdatePasswordResult};
+use lavina_core::player::{PlayerId, PlayerRegistry};
 use lavina_core::prelude::*;
 use lavina_core::repo::Storage;
 use lavina_core::room::RoomRegistry;
@@ -85,8 +86,9 @@ async fn route(
         (&Method::GET, "/metrics") => endpoint_metrics(registry),
         (&Method::GET, "/rooms") => endpoint_rooms(core.rooms).await,
         (&Method::POST, paths::CREATE_PLAYER) => endpoint_create_player(request, storage).await.or5xx(),
+        (&Method::POST, paths::STOP_PLAYER) => endpoint_stop_player(request, core.players).await.or5xx(),
         (&Method::POST, paths::SET_PASSWORD) => endpoint_set_password(request, storage).await.or5xx(),
-        _ => not_found(),
+        _ => endpoint_not_found(),
     };
     Ok(res)
 }
@@ -98,6 +100,7 @@ fn endpoint_metrics(registry: MetricsRegistry) -> Response<Full<Bytes>> {
     Response::new(Full::new(Bytes::from(buffer)))
 }
 
+#[tracing::instrument(skip_all)]
 async fn endpoint_rooms(rooms: RoomRegistry) -> Response<Full<Bytes>> {
     // TODO introduce management API types independent from core-domain types
     // TODO remove `Serialize` implementations from all core-domain types
@@ -105,6 +108,7 @@ async fn endpoint_rooms(rooms: RoomRegistry) -> Response<Full<Bytes>> {
     Response::new(room_list)
 }
 
+#[tracing::instrument(skip_all)]
 async fn endpoint_create_player(
     request: Request<hyper::body::Incoming>,
     mut storage: Storage,
@@ -120,6 +124,27 @@ async fn endpoint_create_player(
     Ok(response)
 }
 
+#[tracing::instrument(skip_all)]
+async fn endpoint_stop_player(
+    request: Request<hyper::body::Incoming>,
+    players: PlayerRegistry,
+) -> Result<Response<Full<Bytes>>> {
+    let str = request.collect().await?.to_bytes();
+    let Ok(res) = serde_json::from_slice::<StopPlayerRequest>(&str[..]) else {
+        return Ok(malformed_request());
+    };
+    let Ok(player_id) = PlayerId::from(res.name) else {
+        return Ok(player_not_found());
+    };
+    let Some(()) = players.stop_player(&player_id).await? else {
+        return Ok(player_not_found());
+    };
+    let mut response = Response::new(Full::<Bytes>::default());
+    *response.status_mut() = StatusCode::NO_CONTENT;
+    Ok(response)
+}
+
+#[tracing::instrument(skip_all)]
 async fn endpoint_set_password(
     request: Request<hyper::body::Incoming>,
     storage: Storage,
@@ -132,14 +157,7 @@ async fn endpoint_set_password(
     match verdict {
         UpdatePasswordResult::PasswordUpdated => {}
         UpdatePasswordResult::UserNotFound => {
-            let payload = ErrorResponse {
+            return Ok(player_not_found());
-                code: errors::PLAYER_NOT_FOUND,
-                message: "No such player exists",
-            }
-            .to_body();
-            let mut response = Response::new(payload);
-            *response.status_mut() = StatusCode::UNPROCESSABLE_ENTITY;
-            return Ok(response);
         }
     }
     let mut response = Response::new(Full::<Bytes>::default());
@@ -147,7 +165,7 @@ async fn endpoint_set_password(
     Ok(response)
 }
 
-pub fn not_found() -> Response<Full<Bytes>> {
+fn endpoint_not_found() -> Response<Full<Bytes>> {
     let payload = ErrorResponse {
         code: errors::INVALID_PATH,
         message: "The path does not exist",
@@ -159,6 +177,17 @@ pub fn not_found() -> Response<Full<Bytes>> {
     response
 }
 
+fn player_not_found() -> Response<Full<Bytes>> {
+    let payload = ErrorResponse {
+        code: errors::PLAYER_NOT_FOUND,
+        message: "No such player exists",
+    }
+    .to_body();
+    let mut response = Response::new(payload);
+    *response.status_mut() = StatusCode::UNPROCESSABLE_ENTITY;
+    response
+}
+
 fn malformed_request() -> Response<Full<Bytes>> {
     let payload = ErrorResponse {
         code: errors::MALFORMED_REQUEST,
@@ -174,6 +203,7 @@ fn malformed_request() -> Response<Full<Bytes>> {
 trait Or5xx {
     fn or5xx(self) -> Response<Full<Bytes>>;
 }
+
 impl Or5xx for Result<Response<Full<Bytes>>> {
     fn or5xx(self) -> Response<Full<Bytes>> {
         self.unwrap_or_else(|e| {
@@ -187,6 +217,7 @@ impl Or5xx for Result<Response<Full<Bytes>>> {
 trait ToBody {
     fn to_body(&self) -> Full<Bytes>;
 }
+
 impl<T> ToBody for T
 where
     T: Serialize,