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use crate::config::WsConfig;
use crate::domain::notification::UserEvent;
use crate::proto::obscura::v1::{WebSocketFrame, web_socket_frame::Payload};
use crate::services::gateway::{Metrics, ack_batcher::AckBatcher, message_pump::MessagePump};
use crate::services::message_service::MessageService;
use crate::services::notification_service::NotificationService;
use axum::extract::ws::{Message as WsMessage, WebSocket};
use futures::{SinkExt, StreamExt};
use prost::Message;
use tokio::sync::{broadcast, mpsc};
use uuid::Uuid;
pub struct Session {
pub user_id: Uuid,
pub request_id: String,
pub socket: WebSocket,
pub message_service: MessageService,
pub notifier: NotificationService,
pub metrics: Metrics,
pub config: WsConfig,
pub shutdown_rx: tokio::sync::watch::Receiver<bool>,
}
impl Session {
#[tracing::instrument(
name = "websocket_session",
skip(self),
fields(
user_id = %self.user_id,
request_id = %self.request_id,
otel.kind = "server",
ws.session_id = %Uuid::new_v4()
)
)]
#[allow(clippy::too_many_lines)]
pub(crate) async fn run(self) {
// Destructuring allows independent mutable access to fields while the socket
// is split into sink and stream halves.
let Self { user_id, socket, message_service, notifier, metrics, config, mut shutdown_rx, .. } = self;
metrics.active_connections.add(1, &[]);
tracing::info!("WebSocket connected");
// Immediately cancel any pending push notifications since the user is now connected.
notifier.cancel_pending_notifications(user_id).await;
let mut notification_rx = notifier.subscribe(user_id).await;
let (mut ws_sink, mut ws_stream) = socket.split();
// Components are initialized here inside the 'websocket_session' span
// to ensure they are recorded as child spans in traces.
let (outbound_tx, mut outbound_rx) = mpsc::channel(config.outbound_buffer_size);
let ack_batcher = AckBatcher::new(
user_id,
message_service.clone(),
metrics.clone(),
config.ack_buffer_size,
config.ack_batch_size,
config.ack_flush_interval_ms,
);
let message_pump = MessagePump::new(
user_id,
message_service.clone(),
outbound_tx,
metrics.clone(),
message_service.batch_limit(),
);
message_pump.notify();
loop {
// Priority is given to shutdown and high-frequency events to ensure
// the server remains responsive to control signals.
if *shutdown_rx.borrow() {
tracing::info!("Shutdown signal received, closing WebSocket");
let _ = ws_sink
.send(WsMessage::Close(Some(axum::extract::ws::CloseFrame {
code: axum::extract::ws::close_code::AWAY,
reason: "Server shutting down".into(),
})))
.await;
break;
}
tokio::select! {
biased;
_ = shutdown_rx.changed() => {}
msg = ws_stream.next() => {
let continue_loop = match msg {
Some(Ok(WsMessage::Binary(bin))) => {
if let Ok(frame) = WebSocketFrame::decode(bin.as_ref()) {
if let Some(Payload::Ack(ack)) = frame.payload {
let mut uuids = Vec::new();
// Support legacy single ID
if !ack.message_id.is_empty() {
if let Ok(id) = Uuid::parse_str(&ack.message_id) {
uuids.push(id);
metrics.acks_received_single_total.add(1, &[]);
} else {
tracing::warn!("Received ACK with invalid UUID: {}", ack.message_id);
}
}
// Support bulk IDs
if !ack.message_ids.is_empty() {
metrics.acks_received_bulk_total.add(1, &[]);
}
for id_str in ack.message_ids {
if let Ok(id) = Uuid::parse_str(&id_str) {
uuids.push(id);
} else {
tracing::warn!("Received ACK with invalid UUID in list: {}", id_str);
}
}
if !uuids.is_empty() {
// Immediately cancel push notifications to avoid "phantom buzzes"
notifier.cancel_pending_notifications(user_id).await;
ack_batcher.push(uuids);
}
} else {
tracing::warn!("Received unexpected Protobuf payload type");
}
} else {
tracing::warn!("Failed to decode WebSocket frame");
}
true
}
Some(Ok(WsMessage::Close(_)) | Err(_)) | None => false,
Some(Ok(WsMessage::Text(t))) => {
tracing::warn!("Received unexpected text message: {}", t);
true
}
Some(Ok(WsMessage::Ping(_))) => {
tracing::debug!("Received heartbeat ping from client");
true
}
Some(Ok(WsMessage::Pong(_))) => {
tracing::debug!("Received heartbeat pong from client");
true
}
};
if !continue_loop { break; }
}
msg = outbound_rx.recv() => {
match msg {
Some(msg) => {
if ws_sink.send(msg).await.is_err() { break; }
}
None => break,
}
}
result = notification_rx.recv() => {
let continue_loop = match result {
Ok(UserEvent::MessageReceived) | Err(broadcast::error::RecvError::Lagged(_)) => {
message_pump.notify();
// Drain prevents queue buildup if notifications arrive faster than processing.
while notification_rx.try_recv() == Ok(UserEvent::MessageReceived) {
message_pump.notify();
}
true
}
Ok(UserEvent::Disconnect) | Err(broadcast::error::RecvError::Closed) => false,
};
if !continue_loop { break; }
}
}
}
let _ = ws_sink.close().await;
// Explicitly abort background tasks to ensure immediate resource cleanup.
ack_batcher.abort();
message_pump.abort();
metrics.active_connections.add(-1, &[]);
tracing::info!("WebSocket disconnected");
}
}