thenodes 0.2.0

TheNodes is a modular, plugin-driven P2P node framework for Rust, supporting node-embedded plugins (NEP) and core-as-a-library (CAL) modes with async-first APIs.
Documentation
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
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
use std::net::SocketAddr;
use std::time::{SystemTime, UNIX_EPOCH};

use crate::events::dispatcher;
use crate::events::model::{LogEvent, LogLevel, SystemEvent};
use crate::network::message::{Message, MessageType, Reason};
use crate::network::peer_manager::PeerManager;
use crate::realms::RealmInfo;

fn now_secs() -> u64 {
    SystemTime::now()
        .duration_since(UNIX_EPOCH)
        .map(|d| d.as_secs())
        .unwrap_or(0)
}

/// Deterministic relay selection via Rendezvous (HRW) hashing
async fn rendezvous_select(
    pm: &PeerManager,
    key: &str,
    require_store_forward: bool,
) -> Option<String> {
    use std::hash::{Hash, Hasher};
    let candidates = pm.list_node_ids().await;
    let mut best_id: Option<String> = None;
    let mut best_score: u64 = 0;
    for nid in candidates {
        // Capability gating: must have relay, and optionally relay_store_forward
        if !pm.peer_has_capability(&nid, "relay").await {
            continue;
        }
        if require_store_forward && !pm.peer_has_capability(&nid, "relay_store_forward").await {
            continue;
        }
        let mut hasher = std::collections::hash_map::DefaultHasher::new();
        (key, &nid).hash(&mut hasher);
        let score = hasher.finish();
        if score > best_score {
            best_score = score;
            best_id = Some(nid);
        }
    }
    best_id
}

pub async fn handle_bind(
    msg: &Message,
    addr: &SocketAddr,
    peer_manager: &PeerManager,
    relay_enabled: bool,
    relay_store_forward_enabled: bool,
    _allow_console: bool,
) {
    if !relay_enabled {
        return;
    }
    if let MessageType::RelayBind {
        target,
        want_store_forward,
        qos,
        nonce,
        expires_at,
    } = &msg.msg_type
    {
        let mut ok = true;
        let mut reason: Option<Reason> = None;
        if want_store_forward.as_ref().cloned().unwrap_or(false) && !relay_store_forward_enabled {
            ok = false;
            reason = Some(Reason::PolicyDenied);
        }
        if ok {
            if let Some(exp) = expires_at.as_ref().cloned() {
                if exp <= now_secs() {
                    ok = false;
                    reason = Some(Reason::Timeout);
                }
            }
        }
        if ok && peer_manager.is_bound(&msg.from, target).await {
            ok = false;
            reason = Some(Reason::AlreadyBound);
        }
        if ok {
            let t = target.trim();
            if t.is_empty() || t == msg.from {
                ok = false;
                reason = Some(Reason::UnknownTarget);
            }
        }
        if ok
            && want_store_forward.as_ref().cloned().unwrap_or(false)
            && !peer_manager.can_enqueue_store_forward(target).await
        {
            ok = false;
            reason = Some(Reason::Overload);
        }
        let present = peer_manager.has_node_id(target).await;
        let reason_snapshot = reason.clone();
        let ack = Message::new(
            &addr.to_string(),
            &addr.to_string(),
            MessageType::RelayBindAck {
                ok,
                reason,
                binding_id: if ok {
                    Some(format!(
                        "bind:{}:{}:{}",
                        msg.from,
                        target,
                        nonce.unwrap_or(0)
                    ))
                } else {
                    None
                },
                peer_present: Some(present),
                nonce: *nonce,
            },
            None,
            msg.realm.clone(),
        );
        let _ = peer_manager.send_to_addr(addr, ack.as_json()).await;
        if !ok && matches!(reason_snapshot, Some(Reason::Overload)) {
            let notify = Message::new(
                &addr.to_string(),
                &addr.to_string(),
                MessageType::RelayNotify {
                    notif_type: Reason::Overload,
                    binding_id: None,
                    detail: Some(format!("target={}", target)),
                },
                None,
                msg.realm.clone(),
            );
            let _ = peer_manager.send_to_addr(addr, notify.as_json()).await;
        }
        if ok {
            let store_fwd = relay_store_forward_enabled
                && want_store_forward.as_ref().cloned().unwrap_or(false);
            let exp = expires_at.as_ref().cloned();
            peer_manager
                .set_binding(&msg.from, target, store_fwd, exp, qos.clone())
                .await;
            if let Some(bid) = nonce.map(|n| format!("bind:{}:{}:{}", msg.from, target, n)) {
                peer_manager.add_binding_id(&bid, &msg.from, target).await;
            }
        }
        // Emit simple system event for traceability
        let mut meta = dispatcher::meta("relay", LogLevel::Info);
        meta.corr_id = Some(dispatcher::correlation_id());
        dispatcher::emit(LogEvent::System(SystemEvent {
            meta,
            action: "relay_bind_processed".into(),
            detail: Some(format!("from={} target={} ok={}", msg.from, target, ok)),
        }));
    }
}

// Ergonomic builders

pub struct RelayBindBuilder {
    to: String,
    want_store_forward: Option<bool>,
    qos: Option<String>,
    ttl_secs: Option<u64>,
}

impl RelayBindBuilder {
    pub fn new(_from: impl Into<String>, to: impl Into<String>) -> Self {
        Self {
            to: to.into(),
            want_store_forward: None,
            qos: None,
            ttl_secs: None,
        }
    }
    pub fn store_forward(mut self, enable: bool) -> Self {
        self.want_store_forward = Some(enable);
        self
    }
    pub fn qos(mut self, qos: impl Into<String>) -> Self {
        self.qos = Some(qos.into());
        self
    }
    pub fn ttl(mut self, secs: u64) -> Self {
        self.ttl_secs = Some(secs);
        self
    }
    pub async fn send(
        self,
        peer_manager: &PeerManager,
        addr: &SocketAddr,
        realm: Option<RealmInfo>,
    ) {
        let nonce = Some(now_secs());
        let expires_at = self.ttl_secs.map(|t| now_secs() + t);
        let msg = Message::new(
            &addr.to_string(),
            &addr.to_string(),
            MessageType::RelayBind {
                target: self.to.clone(),
                want_store_forward: self.want_store_forward,
                qos: self.qos,
                nonce,
                expires_at,
            },
            None,
            realm,
        );
        let _ = peer_manager.send_to_addr(addr, msg.as_json()).await;
    }
}

pub struct RelayForwardBuilder {
    from: String,
    to: String,
    sequence: Option<u64>,
    payload: Option<crate::network::message::Payload>,
}

impl RelayForwardBuilder {
    pub fn new(from: impl Into<String>, to: impl Into<String>) -> Self {
        Self {
            from: from.into(),
            to: to.into(),
            sequence: None,
            payload: None,
        }
    }
    pub fn sequence(mut self, seq: u64) -> Self {
        self.sequence = Some(seq);
        self
    }
    pub fn payload_text(mut self, text: impl Into<String>) -> Self {
        self.payload = Some(crate::network::message::Payload::Text(text.into()));
        self
    }
    pub fn payload_json(mut self, json: serde_json::Value) -> Self {
        self.payload = Some(crate::network::message::Payload::Json(json));
        self
    }
    pub fn payload_binary(mut self, bytes: Vec<u8>) -> Self {
        self.payload = Some(crate::network::message::Payload::Binary(bytes));
        self
    }
    pub async fn send(
        self,
        peer_manager: &PeerManager,
        addr: &SocketAddr,
        realm: Option<RealmInfo>,
    ) {
        let msg = Message::new(
            &addr.to_string(),
            &addr.to_string(),
            MessageType::RelayForward {
                to: self.to.clone(),
                from: self.from.clone(),
                sequence: self.sequence,
            },
            self.payload,
            realm,
        );
        let _ = peer_manager.send_to_addr(addr, msg.as_json()).await;
    }
}

pub async fn handle_forward(
    msg: &Message,
    addr: &SocketAddr,
    peer_manager: &PeerManager,
    relay_enabled: bool,
    relay_store_forward_enabled: bool,
    relay_selection_enabled: bool,
    _allow_console: bool,
) {
    if !relay_enabled {
        return;
    }
    if let MessageType::RelayForward { to, from, sequence } = &msg.msg_type {
        // Dedup/order enforcement: drop if sequence <= last seen
        if let Some(seq) = *sequence {
            if let Some(last) = peer_manager.last_sequence(from, to).await {
                if seq <= last {
                    // Duplicate or out-of-order: drop silently
                    return;
                }
            }
            peer_manager.update_sequence(from, to, seq).await;
        }
        if peer_manager.has_node_id(to).await {
            let _ = peer_manager
                .send_to_node_id(to.as_str(), msg.as_json())
                .await;
            if let Some(seq) = *sequence {
                if peer_manager.binding_qos(&msg.from, to).await.as_deref() == Some("reliable") {
                    peer_manager.add_inflight(&msg.from, to, seq).await;
                    // Schedule a simple timeout-based retry if ACK not received
                    let pm_clone = peer_manager.clone();
                    let addr_clone = *addr;
                    let realm_clone = msg.realm.clone();
                    let to_clone = to.clone();
                    let from_clone = msg.from.clone();
                    // Optional: disable background retry via env for deterministic tests
                    if std::env::var("THENODES_DISABLE_RETRY").is_err() {
                        tokio::spawn(async move {
                            tokio::time::sleep(std::time::Duration::from_millis(500)).await;
                            if pm_clone.is_inflight(&from_clone, &to_clone, seq).await {
                                // Retry once
                                let retry = Message::new(
                                    &addr_clone.to_string(),
                                    &addr_clone.to_string(),
                                    MessageType::RelayForward {
                                        to: to_clone.clone(),
                                        from: from_clone.clone(),
                                        sequence: Some(seq),
                                    },
                                    None,
                                    realm_clone.clone(),
                                );
                                let _ = pm_clone
                                    .send_to_node_id(to_clone.as_str(), retry.as_json())
                                    .await;
                            }
                        });
                    }
                }
            }
            peer_manager.inc_relay_forwarded();
        } else {
            // Try forwarding to a deterministically selected relay peer when enabled
            if relay_selection_enabled {
                if let Some(relay_id) =
                    rendezvous_select(peer_manager, to, relay_store_forward_enabled).await
                {
                    let qos = peer_manager.binding_qos(&msg.from, to).await;
                    let first = peer_manager
                        .send_to_node_id(relay_id.as_str(), msg.as_json())
                        .await;
                    if first.is_err() && qos.as_deref() == Some("reliable") {
                        // Basic Reliable QoS: single retry on immediate send failure
                        let _ = peer_manager
                            .send_to_node_id(relay_id.as_str(), msg.as_json())
                            .await;
                    }
                    // Consider this forwarded via relay
                    peer_manager.inc_relay_forwarded();
                    return;
                }
            }
            peer_manager.inc_relay_dropped();
            // Check QoS: low_latency avoids enqueue
            let qos = peer_manager.binding_qos(&msg.from, to).await;
            if relay_store_forward_enabled
                && peer_manager.binding_store_forward(&msg.from, to).await
                && qos.as_deref() != Some("low_latency")
            {
                let exp = peer_manager.binding_expires_at(&msg.from, to).await;
                if !peer_manager.can_enqueue_store_forward(to).await {
                    let notify = Message::new(
                        &addr.to_string(),
                        &addr.to_string(),
                        MessageType::RelayNotify {
                            notif_type: Reason::Overload,
                            binding_id: None,
                            detail: Some(format!("target={}", to)),
                        },
                        None,
                        msg.realm.clone(),
                    );
                    let _ = peer_manager.send_to_addr(addr, notify.as_json()).await;
                } else if let Some(e) = exp {
                    let now = now_secs();
                    if e <= now {
                        let notify = Message::new(
                            &addr.to_string(),
                            &addr.to_string(),
                            MessageType::RelayNotify {
                                notif_type: Reason::Timeout,
                                binding_id: None,
                                detail: Some(format!("target={}", to)),
                            },
                            None,
                            msg.realm.clone(),
                        );
                        let _ = peer_manager.send_to_addr(addr, notify.as_json()).await;
                    } else {
                        let priority_front = qos.as_deref() == Some("high_throughput");
                        let soft_drop_bulk = qos.as_deref() == Some("bulk");
                        let enq = peer_manager
                            .enqueue_store_forward(
                                to,
                                msg.as_json(),
                                Some(e),
                                priority_front,
                                soft_drop_bulk,
                                Some(msg.from.clone()),
                            )
                            .await;
                        if !enq {
                            let notify = Message::new(
                                &addr.to_string(),
                                &addr.to_string(),
                                MessageType::RelayNotify {
                                    notif_type: Reason::Overload,
                                    binding_id: None,
                                    detail: Some(format!("target={}", to)),
                                },
                                None,
                                msg.realm.clone(),
                            );
                            let _ = peer_manager.send_to_addr(addr, notify.as_json()).await;
                        }
                    }
                } else {
                    let priority_front = qos.as_deref() == Some("high_throughput");
                    let soft_drop_bulk = qos.as_deref() == Some("bulk");
                    let enq = peer_manager
                        .enqueue_store_forward(
                            to,
                            msg.as_json(),
                            None,
                            priority_front,
                            soft_drop_bulk,
                            Some(msg.from.clone()),
                        )
                        .await;
                    if !enq {
                        let notify = Message::new(
                            &addr.to_string(),
                            &addr.to_string(),
                            MessageType::RelayNotify {
                                notif_type: Reason::Overload,
                                binding_id: None,
                                detail: Some(format!("target={}", to)),
                            },
                            None,
                            msg.realm.clone(),
                        );
                        let _ = peer_manager.send_to_addr(addr, notify.as_json()).await;
                    }
                }
            } else {
                let notify = Message::new(
                    &addr.to_string(),
                    &addr.to_string(),
                    MessageType::RelayNotify {
                        notif_type: Reason::Timeout,
                        binding_id: None,
                        detail: Some(format!(
                            "target={} policy=store_forward_disabled_or_low_latency",
                            to
                        )),
                    },
                    None,
                    msg.realm.clone(),
                );
                let _ = peer_manager.send_to_addr(addr, notify.as_json()).await;
            }
        }
    }
}

pub async fn handle_unbind(
    msg: &Message,
    addr: &SocketAddr,
    peer_manager: &PeerManager,
    _allow_console: bool,
) {
    if let MessageType::RelayUnbind { binding_id } = &msg.msg_type {
        if let Some((_from, _to)) = peer_manager.remove_binding_by_id(binding_id).await {
            let notify = Message::new(
                &addr.to_string(),
                &addr.to_string(),
                MessageType::RelayNotify {
                    notif_type: Reason::PeerLeft,
                    binding_id: Some(binding_id.clone()),
                    detail: None,
                },
                None,
                msg.realm.clone(),
            );
            let _ = peer_manager.send_to_addr(addr, notify.as_json()).await;
        }
        let mut meta = dispatcher::meta("relay", LogLevel::Info);
        meta.corr_id = Some(dispatcher::correlation_id());
        dispatcher::emit(LogEvent::System(SystemEvent {
            meta,
            action: "relay_unbind_processed".into(),
            detail: Some(format!("binding_id={}", binding_id)),
        }));
    }
}

pub async fn handle_ack(msg: &Message, _addr: &SocketAddr, peer_manager: &PeerManager) {
    if let MessageType::Ack {
        to, from, sequence, ..
    } = &msg.msg_type
    {
        peer_manager.remove_inflight(from, to, *sequence).await;
    }
}