Persist the channel topic setter as a nick!ident@host mask for KEEPTOPIC and INFO

src/engine/db/channel.rs

@@ -15,7 +15,7 @@ impl Db {
         self.log
             .append(Event::ChannelRegistered { name: name.to_string(), founder: founder.to_string(), ts })
             .map_err(|_| ChanError::Internal)?;
-        self.channels.insert(k, ChannelInfo { name: name.to_string(), founder: founder.to_string(), ts, lock_on: String::new(), lock_off: String::new(), lock_params: Vec::new(), access: Vec::new(), akick: Vec::new(), levels: Vec::new(), successor: None, desc: String::new(), entrymsg: String::new(), url: String::new(), email: String::new(), settings: ChanSettings::default(), topic: String::new(), suspension: None, assigned_bot: None , kickers: KickerSettings::default() , badwords: Vec::new(), badwords_rev: 0 , triggers: Vec::new(), triggers_rev: 0, last_used: ts, noexpire: false, expiry_warned: false, oper_note: None });
+        self.channels.insert(k, ChannelInfo { name: name.to_string(), founder: founder.to_string(), ts, lock_on: String::new(), lock_off: String::new(), lock_params: Vec::new(), access: Vec::new(), akick: Vec::new(), levels: Vec::new(), successor: None, desc: String::new(), entrymsg: String::new(), url: String::new(), email: String::new(), settings: ChanSettings::default(), topic: String::new(), topic_setter: String::new(), suspension: None, assigned_bot: None , kickers: KickerSettings::default() , badwords: Vec::new(), badwords_rev: 0 , triggers: Vec::new(), triggers_rev: 0, last_used: ts, noexpire: false, expiry_warned: false, oper_note: None });
         Ok(())
     }
 
@@ -505,16 +505,18 @@ impl Db {
         Ok(())
     }
 
-    /// Remember a channel's topic (KEEPTOPIC / TOPICLOCK).
-    pub fn set_channel_topic(&mut self, channel: &str, topic: &str) -> Result<(), ChanError> {
+    /// Remember a channel's topic and who set it (KEEPTOPIC / TOPICLOCK / INFO).
+    pub fn set_channel_topic(&mut self, channel: &str, topic: &str, setter: &str) -> Result<(), ChanError> {
         let k = key(channel);
         if !self.channels.contains_key(&k) {
             return Err(ChanError::NoChannel);
         }
         self.log
-            .append(Event::ChannelTopicSet { channel: channel.to_string(), topic: topic.to_string() })
+            .append(Event::ChannelTopicSet { channel: channel.to_string(), topic: topic.to_string(), setter: setter.to_string() })
             .map_err(|_| ChanError::Internal)?;
-        self.channels.get_mut(&k).unwrap().topic = topic.to_string();
+        let c = self.channels.get_mut(&k).unwrap();
+        c.topic = topic.to_string();
+        c.topic_setter = setter.to_string();
         Ok(())
     }
 

src/engine/db/event.rs

@@ -59,7 +59,7 @@ pub enum Event {
     ChannelKickerSet { channel: String, kickers: KickerSettings },
     ChannelBadwordsSet { channel: String, badwords: Vec<String> },
     ChannelTriggersSet { channel: String, triggers: Vec<Trigger> },
-    ChannelTopicSet { channel: String, topic: String },
+    ChannelTopicSet { channel: String, topic: String, #[serde(default)] setter: String },
     ChannelSuspended { channel: String, by: String, reason: String, ts: u64, expires: Option<u64> },
     ChannelUnsuspended { channel: String },
     ChannelBotAssigned { channel: String, bot: String },
@@ -493,7 +493,7 @@ pub(crate) fn apply(accounts: &mut HashMap<String, Account>, channels: &mut Hash
             grouped.remove(&key(&nick));
         }
         Event::ChannelRegistered { name, founder, ts } => {
-            channels.insert(key(&name), ChannelInfo { name, founder, ts, lock_on: String::new(), lock_off: String::new(), lock_params: Vec::new(), access: Vec::new(), akick: Vec::new(), levels: Vec::new(), successor: None, desc: String::new(), entrymsg: String::new(), url: String::new(), email: String::new(), settings: ChanSettings::default(), topic: String::new(), suspension: None, assigned_bot: None , kickers: KickerSettings::default() , badwords: Vec::new(), badwords_rev: 0 , triggers: Vec::new(), triggers_rev: 0, last_used: ts, noexpire: false, expiry_warned: false, oper_note: None });
+            channels.insert(key(&name), ChannelInfo { name, founder, ts, lock_on: String::new(), lock_off: String::new(), lock_params: Vec::new(), access: Vec::new(), akick: Vec::new(), levels: Vec::new(), successor: None, desc: String::new(), entrymsg: String::new(), url: String::new(), email: String::new(), settings: ChanSettings::default(), topic: String::new(), topic_setter: String::new(), suspension: None, assigned_bot: None , kickers: KickerSettings::default() , badwords: Vec::new(), badwords_rev: 0 , triggers: Vec::new(), triggers_rev: 0, last_used: ts, noexpire: false, expiry_warned: false, oper_note: None });
         }
         Event::ChannelDropped { name } => {
             channels.remove(&key(&name));
@@ -585,9 +585,10 @@ pub(crate) fn apply(accounts: &mut HashMap<String, Account>, channels: &mut Hash
                 c.triggers_rev = c.triggers_rev.wrapping_add(1);
             }
         }
-        Event::ChannelTopicSet { channel, topic } => {
+        Event::ChannelTopicSet { channel, topic, setter } => {
             if let Some(c) = channels.get_mut(&key(&channel)) {
                 c.topic = topic;
+                c.topic_setter = setter;
             }
         }
         Event::ChannelSuspended { channel, by, reason, ts, expires } => {

src/engine/db/mod.rs

@@ -501,6 +501,10 @@ pub struct ChannelInfo {
     // Last known topic, kept for KEEPTOPIC / TOPICLOCK.
     #[serde(default)]
     pub topic: String,
+    // Nick credited with setting `topic`, restored as the FTOPIC "setby" on
+    // KEEPTOPIC and shown in INFO. Empty if unknown (e.g. pre-upgrade state).
+    #[serde(default)]
+    pub topic_setter: String,
     // Services suspension, if any (channel frozen while set and unexpired).
     #[serde(default)]
     pub suspension: Option<Suspension>,
@@ -1384,7 +1388,7 @@ impl Db {
                 snapshot.push(Event::ChannelSettingsSet { channel: c.name.clone(), settings: c.settings });
             }
             if !c.topic.is_empty() {
-                snapshot.push(Event::ChannelTopicSet { channel: c.name.clone(), topic: c.topic.clone() });
+                snapshot.push(Event::ChannelTopicSet { channel: c.name.clone(), topic: c.topic.clone(), setter: c.topic_setter.clone() });
             }
             if let Some(s) = &c.suspension {
                 snapshot.push(Event::ChannelSuspended { channel: c.name.clone(), by: s.by.clone(), reason: s.reason.clone(), ts: s.ts, expires: s.expires });

src/engine/db/store.rs

@@ -515,8 +515,8 @@ impl Store for Db {
     fn triggers(&self, channel: &str) -> Vec<TriggerView> {
         Db::triggers(self, channel).iter().map(|t| TriggerView { pattern: t.pattern.clone(), response: t.response.clone(), cooldown: t.cooldown }).collect()
     }
-    fn set_channel_topic(&mut self, channel: &str, topic: &str) -> Result<(), ChanError> {
-        Db::set_channel_topic(self, channel, topic)
+    fn set_channel_topic(&mut self, channel: &str, topic: &str, setter: &str) -> Result<(), ChanError> {
+        Db::set_channel_topic(self, channel, topic, setter)
     }
     fn suspend_channel(&mut self, channel: &str, by: &str, reason: &str, expires: Option<u64>) -> Result<(), ChanError> {
         Db::suspend_channel(self, channel, by, reason, expires)
@@ -661,6 +661,7 @@ fn channel_view(c: &ChannelInfo) -> ChannelView {
         keeptopic: c.settings.keeptopic,
         topiclock: c.settings.topiclock,
         topic: c.topic.clone(),
+        topic_setter: c.topic_setter.clone(),
         suspended: c.suspension.as_ref().is_some_and(|s| s.expires.is_none_or(|e| e > now())),
         assigned_bot: c.assigned_bot.clone(),
         bot_greet: c.settings.bot_greet,

src/engine/mod.rs

@@ -1412,9 +1412,10 @@ impl Engine {
                 match self.db.channel(&channel) {
                     Some(info) => {
                         let mut out = vec![NetAction::ChannelMode { from: from.clone(), channel: channel.clone(), modes: info.lock_modes() }];
-                        // KEEPTOPIC: restore the remembered topic on a recreated channel.
+                        // KEEPTOPIC: restore the remembered topic on a recreated channel,
+                        // credited to whoever originally set it.
                         if info.settings.keeptopic && !info.topic.is_empty() {
-                            out.push(NetAction::Topic { from, channel, topic: info.topic.clone() });
+                            out.push(NetAction::Topic { from, channel, topic: info.topic.clone(), setter: info.topic_setter.clone() });
                         }
                         out
                     }
@@ -1563,20 +1564,34 @@ impl Engine {
                 self.network.set_channel_key(&channel, key);
                 Vec::new()
             }
-            NetEvent::TopicChange { channel, setter, topic } => {
+            NetEvent::TopicChange { channel, setter, topic, setby } => {
                 let watch = self.notify_line('t', &setter, Some(&channel), &format!("changed the topic of {channel}"));
-                let info = self.db.channel(&channel).map(|c| (c.settings.keeptopic, c.settings.topiclock, c.topic.clone()));
+                // Who set it, as a stable nick!ident@host — NEVER the source uid, which
+                // is recycled to another user the instant this connection drops. Prefer
+                // the ircd's own setby mask; else snapshot the still-connected source.
+                let author = if !setby.is_empty() {
+                    setby
+                } else {
+                    match self.network.nick_of(&setter) {
+                        Some(nick) => match (self.network.ident_of(&setter), self.network.host_of(&setter)) {
+                            (Some(ident), Some(host)) => format!("{nick}!{ident}@{host}"),
+                            _ => nick.to_string(),
+                        },
+                        None => String::new(),
+                    }
+                };
+                let info = self.db.channel(&channel).map(|c| (c.settings.keeptopic, c.settings.topiclock, c.topic.clone(), c.topic_setter.clone()));
                 // The setter may change a locked topic only with op-level access.
                 let authorized = self.network.account_of(&setter).and_then(|a| self.db.channel(&channel).map(|c| c.is_op(a))).unwrap_or(false);
                 let mut out: Vec<NetAction> = match info {
-                    // TOPICLOCK + unauthorised: put the kept topic back.
-                    Some((_, true, stored)) if !authorized => {
+                    // TOPICLOCK + unauthorised: put the kept topic back, keeping its author.
+                    Some((_, true, stored, stored_by)) if !authorized => {
                         let from = self.chan_service.clone().unwrap_or_default();
-                        vec![NetAction::Topic { from, channel, topic: stored }]
+                        vec![NetAction::Topic { from, channel, topic: stored, setter: stored_by }]
                     }
                     // Otherwise remember the new topic if the channel keeps it.
-                    Some((keep, lock, _)) if keep || lock => {
-                        let _ = self.db.set_channel_topic(&channel, &topic);
+                    Some((keep, lock, _, _)) if keep || lock => {
+                        let _ = self.db.set_channel_topic(&channel, &topic, &author);
                         Vec::new()
                     }
                     _ => Vec::new(),

src/engine/tests.rs

@@ -3810,11 +3810,11 @@
         db.register_channel("#c", "boss").unwrap();
         db.set_channel_setting("#c", db::ChanSetting::KeepTopic, true).unwrap();
         db.set_channel_setting("#c", db::ChanSetting::TopicLock, true).unwrap();
-        db.set_channel_topic("#c", "Official topic").unwrap();
+        db.set_channel_topic("#c", "Official topic", "alice").unwrap();
         let mut e = Engine::new(vec![Box::new(ChanServ { uid: "42SAAAAAB".into() })], db);
         e.handle(NetEvent::UserConnect { uid: "000AAAAAB".into(), nick: "rando".into(), host: "h".into() , ip: "0.0.0.0".into() });
         // A user without access changes the topic -> reverted to the stored one.
-        let out = e.handle(NetEvent::TopicChange { channel: "#c".into(), setter: "000AAAAAB".into(), topic: "hacked".into() });
+        let out = e.handle(NetEvent::TopicChange { channel: "#c".into(), setter: "000AAAAAB".into(), topic: "hacked".into(), setby: String::new() });
         assert!(out.iter().any(|a| matches!(a, NetAction::Topic { topic, .. } if topic == "Official topic")), "topiclock reverts: {out:?}");
         // KEEPTOPIC restores the remembered topic on channel (re)creation.
         let out = e.handle(NetEvent::ChannelCreate { channel: "#c".into() });