SQLite engine: notify/listen — auto-commit notify, watcher-fanout WakeReceiver bridge (task sqlite-engine-notify-listen)

alkstore-sqlite/src/store.rs

@@ -34,6 +34,7 @@
 use alkstore::Store;
 use std::path::PathBuf;
 use std::sync::Arc;
+use std::sync::atomic::AtomicBool;
 
 use crate::opts::SqliteOpts;
 use crate::seam::{database_error, sqlite_error};
@@ -48,6 +49,7 @@ pub struct SqliteStore {
     readers: Arc<Readers>,
     watcher: Arc<SharedUpdateWatcher>,
     db_path: PathBuf,
+    closed: Arc<AtomicBool>,
 }
 
 impl std::fmt::Debug for SqliteStore {
@@ -64,6 +66,7 @@ impl SqliteStore {
     /// reader pool, and closes the writer slot. Idempotent. [`Drop`]
     /// delegates here.
     pub fn close(&self) {
+        self.closed.store(true, std::sync::atomic::Ordering::SeqCst);
         let _ = self.watcher.close();
         self.readers.close();
         self.writer.close();
@@ -105,6 +108,7 @@ fn open_store(path: &str, opts: SqliteOpts) -> alkstore::Result<SqliteStore> {
         readers: Arc::new(Readers::new(path.to_string(), opts.max_readers)),
         watcher: Arc::new(watcher),
         db_path: PathBuf::from(path),
+        closed: Arc::new(AtomicBool::new(false)),
     })
 }
 
@@ -122,25 +126,20 @@ impl Store for SqliteStore {
 
     fn notify<'a>(
         &'a self,
-        _channel: &str,
-        _payload: serde_json::Value,
+        channel: &str,
+        payload: serde_json::Value,
     ) -> alkstore::BoxedFuture<'a, alkstore::Result<()>> {
-        Box::pin(async {
-            Err(database_error(
-                "notify wiring lands with the mechanism tasks",
-            ))
-        })
+        crate::notify::notify(self.writer.clone(), channel, payload)
     }
 
     fn listen<'a>(
         &'a self,
-        _channel: &str,
+        channel: &str,
     ) -> alkstore::BoxedFuture<'a, alkstore::Result<Box<dyn alkstore::WakeReceiver>>> {
-        Box::pin(async {
-            Err(database_error(
-                "listen wiring lands with the mechanism tasks",
-            ))
-        })
+        let watcher = self.watcher.clone();
+        let closed = self.closed.clone();
+        let channel = channel.to_string();
+        Box::pin(async move { crate::notify::listen(watcher, closed, &channel) })
     }
 
     fn stream<'a>(
@@ -221,6 +220,8 @@ impl Store for SqliteStore {
     }
 }
 
+#[cfg(test)]
+mod notify_tests;
 #[cfg(test)]
 mod open_tests;
 #[cfg(test)]