Drop the spent DeadAir clean-up and keep not-due skips off live updates (#196, #197)

The clean-up of DeadAir's old copies probed for its table on every open, and on
Postgres each failed probe is an ERROR in the server's log: 120 an hour from the
healthcheck alone. Production ran it already and is the only database.

A scan sent a not-due skip for each of ~1,535 feeds into a broadcast of 1,024,
so a page slow to read lagged and dropped events: 443 counted in five hours.
Nothing listening uses them; the terminal and the log still get them.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/db.rs

@@ -99,22 +99,6 @@ async fn create_missing(orm: &sea_orm::DatabaseConnection) -> Result<()> {
         let sql = "ALTER TABLE deadair_prefs ADD COLUMN pause_ms BIGINT";
         orm.execute_unprepared(sql).await.with_context(|| sql.to_owned())?;
     }
-    // DeadAir made a shortened copy of each file until it played the original through a
-    // playlist (#181). The copies go with their table, and the files are looked at again, which
-    // takes seconds each. Found only while the table is there, so nothing is written after.
-    let copies = Statement::from_string(orm.get_database_backend(), "SELECT path FROM deadair WHERE path IS NOT NULL");
-    if let Ok(rows) = orm.query_all_raw(copies).await {
-        for r in rows {
-            // Only DeadAir's own files, `name.deadair.mp3`: anything else would be someone's original.
-            if let Ok(path) = r.try_get::<String>("", "path")
-                && path.contains(".deadair.")
-            {
-                let _ = std::fs::remove_file(&path);
-            }
-        }
-        // IF EXISTS: the healthcheck's `ipx status` may open the database at the same moment.
-        orm.execute_unprepared("DROP TABLE IF EXISTS deadair").await.context("dropping DeadAir's copies")?;
-    }
     Ok(())
 }
 
@@ -2489,29 +2473,6 @@ pub fn now() -> i64 {
 mod tests {
     use super::*;
 
-    #[tokio::test]
-    async fn deadair_drops_its_old_copies_once() {
-        let db = Db::memory().await.unwrap();
-        let dir = std::env::temp_dir().join(format!("ipx-deadair-old-{}", std::process::id()));
-        std::fs::create_dir_all(&dir).unwrap();
-        let (orig, copy) = (dir.join("a.mp3"), dir.join("a.deadair.mp3"));
-        std::fs::write(&orig, "original").unwrap();
-        std::fs::write(&copy, "copy").unwrap();
-        db.orm.execute_unprepared("CREATE TABLE deadair (enclosure_id BIGINT PRIMARY KEY, path TEXT)").await.unwrap();
-        for (id, path) in [(1, &copy), (2, &orig)] {
-            db.orm
-                .execute_unprepared(&format!("INSERT INTO deadair VALUES ({id}, '{}')", path.display()))
-                .await
-                .unwrap();
-        }
-        create_missing(&db.orm).await.unwrap();
-        assert!(!copy.exists(), "the copy goes");
-        assert!(orig.exists(), "a path that is not DeadAir's own is never removed");
-        assert!(db.orm.execute_unprepared("SELECT 1 FROM deadair").await.is_err(), "and the table");
-        create_missing(&db.orm).await.unwrap();
-        std::fs::remove_dir_all(&dir).unwrap();
-    }
-
     #[tokio::test]
     async fn deadair_looks_at_a_file_once_per_download_and_counts_an_episode_once() {
         let db = Db::memory().await.unwrap();

src/ipc.rs

@@ -144,7 +144,12 @@ impl Emitter {
         // line per feed per tick for "not due yet" would push everything worth reading
         // out of the buffer within a few minutes.
         log_event(&e, self.tx.is_some());
-        if let Some(tx) = &self.tx {
+        // A feed not due changes nothing a listener shows, and a scan has one for nearly every
+        // feed: 1,500 at once overflowed the channel's 1,024 for a page slow to read (#197).
+        let routine = matches!(&e, Event::FeedSkip { reason, .. } if reason.starts_with("not due"));
+        if let Some(tx) = &self.tx
+            && !routine
+        {
             // An error here only means nobody is listening yet.
             let _ = tx.send(e.clone());
         }
@@ -362,6 +367,17 @@ pub async fn proxy(path: &Path, cmd: &Command) -> Result<()> {
 mod tests {
     use super::*;
 
+    #[test]
+    fn a_feed_not_due_stays_off_the_live_updates() {
+        let (tx, mut rx) = broadcast::channel(4);
+        let out = Emitter::socket(tx, false);
+        for i in 0..10 {
+            out.emit(Event::FeedSkip { feed: format!("f{i}"), reason: "not due for 5m".into() });
+        }
+        out.emit(Event::FeedSkip { feed: "g".into(), reason: "not modified".into() });
+        assert!(matches!(rx.try_recv(), Ok(Event::FeedSkip { feed, .. }) if feed == "g"), "nothing missed");
+    }
+
     #[test]
     fn a_feed_that_moved_says_so_on_the_wire_and_in_words() {
         let e = Event::FeedMoved { feed: "x".into(), from: "http://a/f".into(), to: "https://a/f".into() };

src/web.rs

@@ -1970,15 +1970,15 @@ async fn events(
     Sse::new(futures_util::StreamExt::flatten(stream)).keep_alive(axum::response::sse::KeepAlive::default())
 }
 
-/// The feed an event changed what the list shows of: its counts, error or last check. Not the
-/// routine skip of a feed not due, dozens a minute that change nothing.
+/// The feed an event changed what the list shows of: its counts, error or last check. The
+/// routine skip of a feed not due never reaches here (`Emitter::emit`).
 fn changed_feed(ev: &Event) -> Option<&str> {
     match ev {
         Event::FeedDone { feed, .. }
         | Event::FeedError { feed, .. }
         | Event::FeedMoved { feed, .. }
         | Event::DownloadDone { feed, .. } => Some(feed),
-        Event::FeedSkip { feed, reason } if !reason.starts_with("not due") => Some(feed),
+        Event::FeedSkip { feed, .. } => Some(feed),
         _ => None,
     }
 }