add NIP-29 LiveKit token and fork detection

crates/nip29/src/lib.rs

@@ -19,11 +19,13 @@ pub use protocol::*;
 pub(crate) static LOCAL_KEYS: LazyLock<Keys> = LazyLock::new(Keys::generate);
 
 const LIST_SUBSCRIPTION: &str = "nip29-list";
+const FORK_SUBSCRIPTION: &str = "nip29-forks";
 const GROUP_PREFIX: &str = "grp-";
 const BROWSE_PREFIX: &str = "brw-";
 const PAGE_PREFIX: &str = "pg-";
 const BROWSE_LIMIT: usize = 500;
 const BROWSE_TIMEOUT: Duration = Duration::from_secs(10);
+const FORK_INTERVAL: Duration = Duration::from_secs(15 * 60);
 
 pub fn init(cx: &mut App) {
     GroupsRegistry::set_global(cx.new(GroupsRegistry::new), cx);
@@ -51,12 +53,17 @@ enum Signal {
     Event(SubscriptionId, Event),
     Eose(SubscriptionId),
     Closed(SubscriptionId, String),
+    Forks,
 }
 
 fn list_subscription_id() -> SubscriptionId {
     SubscriptionId::new(LIST_SUBSCRIPTION)
 }
 
+fn fork_subscription_id() -> SubscriptionId {
+    SubscriptionId::new(FORK_SUBSCRIPTION)
+}
+
 fn subscription_id(key: &GroupKey) -> SubscriptionId {
     SubscriptionId::new(format!("{GROUP_PREFIX}{:08x}", key.uniq_id() as u32))
 }
@@ -79,6 +86,7 @@ fn is_page(id: &SubscriptionId) -> bool {
 fn is_own_subscription(id: &SubscriptionId) -> bool {
     let id = id.as_str();
     id == LIST_SUBSCRIPTION
+        || id == FORK_SUBSCRIPTION
         || id.starts_with(GROUP_PREFIX)
         || id.starts_with(BROWSE_PREFIX)
         || id.starts_with(PAGE_PREFIX)
@@ -92,6 +100,8 @@ pub struct GroupsRegistry {
     browse: HashMap<SubscriptionId, Browse>,
     routes: HashMap<SubscriptionId, GroupKey>,
     observers: HashMap<GroupKey, Subscription>,
+    forks: HashMap<PublicKey, (Timestamp, GroupList)>,
+    fork_authors: HashSet<PublicKey>,
     signal_tx: flume::Sender<Signal>,
     signal_rx: flume::Receiver<Signal>,
     notification_listener: Option<Task<()>>,
@@ -142,6 +152,8 @@ impl GroupsRegistry {
             browse: HashMap::new(),
             routes: HashMap::new(),
             observers: HashMap::new(),
+            forks: HashMap::new(),
+            fork_authors: HashSet::new(),
             signal_tx: tx,
             signal_rx: rx,
             notification_listener: None,
@@ -317,6 +329,8 @@ impl GroupsRegistry {
 
         self.groups.clear();
         self.observers.clear();
+        self.forks.clear();
+        self.fork_authors.clear();
         self.list = GroupList::default();
 
         let nostr = NostrRegistry::global(cx);
@@ -324,6 +338,7 @@ impl GroupsRegistry {
 
         let mut ids: Vec<SubscriptionId> = routes.into_keys().collect();
         ids.push(list_subscription_id());
+        ids.push(fork_subscription_id());
         ids.extend(self.browse.keys().cloned());
 
         self.browse.clear();
@@ -368,6 +383,8 @@ impl GroupsRegistry {
                 }
                 Err(error) => log::warn!("nip29: loading the group list failed: {error}"),
             }));
+
+        self.watch_forks(cx);
     }
 
     fn merge(&mut self, list: GroupList, cx: &mut Context<Self>) {
@@ -382,6 +399,101 @@ impl GroupsRegistry {
         cx.notify();
     }
 
+    fn watch_forks(&mut self, cx: &mut Context<Self>) {
+        let executor = cx.background_executor().clone();
+        let tx = self.signal_tx.clone();
+
+        self.tasks.push(cx.background_spawn(async move {
+            loop {
+                executor.timer(FORK_INTERVAL).await;
+
+                if tx.send_async(Signal::Forks).await.is_err() {
+                    break;
+                }
+            }
+        }));
+    }
+
+    fn admin_keys(&self, cx: &App) -> HashSet<PublicKey> {
+        let mut keys = HashSet::new();
+
+        for group in &self.groups {
+            for (admin, _) in group.read(cx).admins().entries() {
+                keys.insert(*admin);
+            }
+        }
+
+        keys
+    }
+
+    fn sync_forks(&mut self, force: bool, cx: &mut Context<Self>) {
+        let authors = self.admin_keys(cx);
+
+        if authors.is_empty() || (!force && authors == self.fork_authors) {
+            return;
+        }
+
+        let nostr = NostrRegistry::global(cx);
+        let client = nostr.read(cx).client();
+        let filter = Filter::new()
+            .authors(authors.iter().copied())
+            .kind(Kind::SimpleGroups);
+
+        self.fork_authors = authors;
+
+        self.tasks.push(cx.background_spawn(async move {
+            if let Err(error) = client
+                .subscribe(ReqTarget::auto([filter]))
+                .with_id(fork_subscription_id())
+                .await
+            {
+                log::warn!("nip29: subscribing to the admins' group lists failed: {error}");
+            }
+        }));
+    }
+
+    fn absorb_fork_list(&mut self, event: &Event, cx: &mut Context<Self>) {
+        let Ok(list) = GroupList::parse(event) else {
+            log::warn!("nip29: ignoring a malformed admin group list");
+            return;
+        };
+
+        let author = event.pubkey;
+
+        if let Some((seen, _)) = self.forks.get(&author)
+            && *seen >= event.created_at
+        {
+            return;
+        }
+
+        self.forks.insert(author, (event.created_at, list));
+        self.evaluate_forks(cx);
+    }
+
+    fn evaluate_forks(&mut self, cx: &mut Context<Self>) {
+        let groups = self.groups.clone();
+
+        for group in groups {
+            let elsewhere = {
+                let group = group.read(cx);
+                let key = group.key();
+
+                group
+                    .admins()
+                    .entries()
+                    .iter()
+                    .filter_map(|(admin, _)| self.forks.get(admin))
+                    .flat_map(|(_, list)| list.entries())
+                    .find(|entry| entry.id == *key.id() && entry.relay != *key.relay())
+                    .map(|entry| GroupKey::new(entry.relay.clone(), entry.id.clone()))
+            };
+
+            group.update(cx, |group, cx| {
+                group.set_elsewhere(elsewhere, cx);
+            });
+        }
+    }
+
     fn ensure(&mut self, key: GroupKey, cx: &mut Context<Self>) {
         if self.group(&key, cx).is_some() {
             return;
@@ -399,6 +511,7 @@ impl GroupsRegistry {
                 }
                 GroupEvent::Updated => {
                     this.refresh_entry(group, cx);
+                    this.sync_forks(false, cx);
                 }
                 _ => {}
             }),
@@ -572,6 +685,11 @@ impl GroupsRegistry {
             return;
         }
 
+        if id == fork_subscription_id() {
+            self.absorb_fork_list(&event, cx);
+            return;
+        }
+
         if self.browse.contains_key(&id) {
             self.absorb_candidate(&id, &event, cx);
             return;
@@ -660,6 +778,11 @@ impl GroupsRegistry {
             return;
         }
 
+        if id == fork_subscription_id() {
+            log::warn!("nip29: the admins' group lists were refused: {reason}");
+            return;
+        }
+
         let Some(key) = self.routes.get(&id).cloned() else {
             return;
         };
@@ -761,6 +884,9 @@ impl GroupsRegistry {
                     Signal::Closed(id, reason) => {
                         this.handle_closed(id, reason, cx);
                     }
+                    Signal::Forks => {
+                        this.sync_forks(true, cx);
+                    }
                 })
                 .ok();
             }