1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
use std::collections::HashMap;
use std::sync::Arc;
use parking_lot::Mutex;
use tokio::sync::{broadcast, mpsc};
use tracing::warn;
use crate::jsonrpc::{JsonRpcNotification, JsonRpcRequest};
use crate::types::{SessionEventNotification, SessionId};
/// Per-session channels created by the router during session registration.
pub(crate) struct SessionChannels {
/// Filtered `session.event` notifications for this session.
pub(crate) notifications: mpsc::UnboundedReceiver<SessionEventNotification>,
/// Filtered JSON-RPC requests (tool.call, userInput.request, etc.) for this session.
pub(crate) requests: mpsc::UnboundedReceiver<JsonRpcRequest>,
}
struct SessionSenders {
notifications: mpsc::UnboundedSender<SessionEventNotification>,
requests: mpsc::UnboundedSender<JsonRpcRequest>,
}
/// Routes notifications and requests by sessionId to per-session channels.
///
/// Internal to the SDK — consumers interact via `Client::register_session()`.
pub(crate) struct SessionRouter {
sessions: Arc<Mutex<HashMap<SessionId, SessionSenders>>>,
started: Mutex<bool>,
}
impl SessionRouter {
pub(crate) fn new() -> Self {
Self {
sessions: Arc::new(Mutex::new(HashMap::new())),
started: Mutex::new(false),
}
}
/// Register a session to receive filtered events and requests.
pub(crate) fn register(&self, session_id: &SessionId) -> SessionChannels {
let (notif_tx, notif_rx) = mpsc::unbounded_channel();
let (req_tx, req_rx) = mpsc::unbounded_channel();
self.sessions.lock().insert(
session_id.clone(),
SessionSenders {
notifications: notif_tx,
requests: req_tx,
},
);
SessionChannels {
notifications: notif_rx,
requests: req_rx,
}
}
/// Unregister a session, dropping its channels.
pub(crate) fn unregister(&self, session_id: &SessionId) {
self.sessions.lock().remove(session_id.as_str());
}
/// Snapshot every currently-registered session ID.
///
/// Used by [`Client::stop`](crate::Client::stop) to iterate active
/// sessions for cooperative shutdown without holding the router lock
/// across `.await`.
pub(crate) fn session_ids(&self) -> Vec<SessionId> {
self.sessions.lock().keys().cloned().collect()
}
/// Drop all registered session channels.
///
/// Used by [`Client::force_stop`](crate::Client::force_stop) to release
/// per-session state without waiting for graceful unregistration.
pub(crate) fn clear(&self) {
self.sessions.lock().clear();
}
/// Start the router tasks if not already running.
///
/// Takes the notification broadcast and request channel from the Client.
/// If `request_rx` is `None` (already taken by `take_request_rx()`),
/// only notification routing is available.
pub(crate) fn ensure_started(
&self,
notification_tx: &broadcast::Sender<JsonRpcNotification>,
request_rx: &Mutex<Option<mpsc::UnboundedReceiver<JsonRpcRequest>>>,
) {
let mut started = self.started.lock();
if *started {
return;
}
*started = true;
// Notification routing task
let sessions = self.sessions.clone();
let mut notif_rx = notification_tx.subscribe();
tokio::spawn(async move {
loop {
match notif_rx.recv().await {
Ok(notification) => {
if notification.method != "session.event" {
continue;
}
let Some(ref params) = notification.params else {
continue;
};
let Some(session_id) = params.get("sessionId").and_then(|v| v.as_str())
else {
continue;
};
let sender = {
let guard = sessions.lock();
guard.get(session_id).map(|s| s.notifications.clone())
};
if let Some(sender) = sender {
match serde_json::from_value::<SessionEventNotification>(params.clone())
{
Ok(event_notification) => {
let _ = sender.send(event_notification);
}
Err(e) => {
warn!(
error = %e,
session_id = session_id,
"failed to deserialize session event notification"
);
}
}
}
// Unknown session IDs are silently dropped — the session
// may have been unregistered between dispatch and delivery.
}
Err(broadcast::error::RecvError::Lagged(n)) => {
warn!(missed = n, "notification router lagged");
}
Err(broadcast::error::RecvError::Closed) => break,
}
}
});
// Request routing task (if request_rx is available)
if let Some(mut rx) = request_rx.lock().take() {
let sessions = self.sessions.clone();
tokio::spawn(async move {
while let Some(request) = rx.recv().await {
let session_id = request
.params
.as_ref()
.and_then(|p| p.get("sessionId"))
.and_then(|v| v.as_str());
if let Some(sid) = session_id {
let sender = {
let guard = sessions.lock();
guard.get(sid).map(|s| s.requests.clone())
};
if let Some(sender) = sender {
let _ = sender.send(request);
} else {
warn!(
session_id = sid,
method = %request.method,
"request for unregistered session"
);
}
} else {
warn!(
method = %request.method,
"request missing sessionId"
);
}
}
});
}
}
}