Retire davewiner's 922 rows, without taking the ones people still read

davewiner's OPML left config.toml before retire_group existed, so its
derived rows were skipped by every scan but never cleared. At startup the
daemon now retires every group whose parent is gone from config. And
retire_group unmanages a feed that has its own config entry instead of
dropping it: eleven of davewiner's were promoted without being unmanaged,
and dropping them as derived would have deleted their entries. That also
covers removing an OPML or Patreon subscription from the page.

Closes #3.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/main.rs

@@ -392,6 +392,12 @@ async fn daemon(
         Err(e) => tracing::warn!(error = ?e, "could not requeue interrupted downloads"),
     }
 
+    match retire_stranded(&ctx) {
+        Ok(0) => {}
+        Ok(n) => tracing::info!(feeds = n, "retired feeds whose OPML is no longer in config"),
+        Err(e) => tracing::warn!(error = ?e, "could not retire feeds whose OPML is no longer in config"),
+    }
+
     let (tx_cmd, mut rx_cmd) = mpsc::channel::<Cmd>(64);
 
     let web = start_web(&ctx, &config_path, web_addr, &tx_cmd, &events).await?;
@@ -962,10 +968,16 @@ pub fn subscriptions(ctx: &Ctx) -> Result<Vec<Sub>> {
 /// Patreon feed that listed them: the same rule `sync_group` applies to one the list drops --
 /// removed if nothing was downloaded, orphaned and kept otherwise. Called once the parent
 /// itself is removed, since `subscriptions()` would otherwise keep scanning them under a
-/// fallback policy meant for a feed with no parent at all.
+/// fallback policy meant for a feed with no parent at all. A feed promoted to config is not
+/// derived any more, so it is only unmanaged.
 pub fn retire_group(ctx: &Ctx, parent_id: &str) -> Result<()> {
+    let cfg = ctx.cfg();
     for m in ctx.db.managed_feeds()?.into_iter().filter(|m| m.group_id == parent_id) {
-        if ctx.db.downloaded_count(&m.id).unwrap_or(1) > 0 {
+        if cfg.feeds.contains_key(&m.id) {
+            // Scanned from its config entry and still read. Dropped as derived, its stored
+            // entries would go with it: davewiner's 11 were promoted without being unmanaged.
+            ctx.db.unmanage(&m.id)?;
+        } else if ctx.db.downloaded_count(&m.id).unwrap_or(1) > 0 {
             ctx.db.set_orphaned(&m.id, true)?;
         } else {
             ctx.db.drop_managed(&m.id)?;
@@ -974,6 +986,24 @@ pub fn retire_group(ctx: &Ctx, parent_id: &str) -> Result<()> {
     Ok(())
 }
 
+/// Retires every group whose parent is gone from config, and returns how many derived rows that
+/// dropped or unmanaged. An OPML removed before `retire_group` existed left its feeds behind:
+/// davewiner's 922 were skipped by every scan and never cleared, and their stale errors were
+/// most of the ones stored.
+fn retire_stranded(ctx: &Ctx) -> Result<usize> {
+    let cfg = ctx.cfg();
+    let before = ctx.db.managed_feeds()?;
+    let stranded: std::collections::BTreeSet<&str> = before
+        .iter()
+        .map(|m| m.group_id.as_str())
+        .filter(|g| !cfg.feeds.contains_key(*g))
+        .collect();
+    for group in stranded {
+        retire_group(ctx, group)?;
+    }
+    Ok(before.len() - ctx.db.managed_feeds()?.len())
+}
+
 /// Seconds to wait before re-checking a feed.
 ///
 /// A per-feed schedule is an explicit instruction and wins outright. Without one, the
@@ -1713,4 +1743,24 @@ mod tests {
         assert!(managed.iter().any(|m| m.id == "has-file"), "has a file on disk, so it is kept");
         assert!(ctx.db.feed_summary("has-file").unwrap().orphaned, "and flagged as orphaned");
     }
+
+    #[test]
+    fn a_stranded_group_is_retired_but_a_promoted_feed_keeps_its_entries() {
+        // davewiner: the OPML left config before retire_group existed, and 11 of its feeds
+        // promoted to config since still said managed = 1.
+        let mut cfg = config::Config::default();
+        cfg.feeds.insert("promoted".into(), feed());
+        cfg.feeds.insert("live-opml".into(), feed());
+        let ctx = test_ctx(cfg);
+        ctx.db.upsert_managed("promoted", "http://x/p.xml", "Promoted", "gone-opml").unwrap();
+        ctx.db.upsert_managed("empty", "http://x/e.xml", "Empty", "gone-opml").unwrap();
+        ctx.db.upsert_managed("listed", "http://x/l.xml", "Listed", "live-opml").unwrap();
+        ctx.db.record_entry("promoted", &feed::Entry { guid: "g1".into(), ..Default::default() }).unwrap();
+
+        assert_eq!(retire_stranded(&ctx).unwrap(), 2, "empty dropped, promoted unmanaged");
+
+        let managed: Vec<String> = ctx.db.managed_feeds().unwrap().into_iter().map(|m| m.id).collect();
+        assert_eq!(managed, ["listed"], "a group still in config is left alone");
+        assert_eq!(ctx.db.feed_summary("promoted").unwrap().entries, 1, "its entries survive");
+    }
 }