fix(arr): re-read the command timeout every batch

crates/arr-subs/src/command.rs

@@ -18,7 +18,12 @@
 //! exit, timeout and unparseable output fail loudly here, and a reply with
 //! the wrong cue count or numbering never becomes a subtitle.
 
-use std::{io::ErrorKind, process::Stdio, time::Duration};
+use std::{
+    io::ErrorKind,
+    process::Stdio,
+    sync::{atomic::AtomicU64, atomic::Ordering, Arc},
+    time::Duration,
+};
 
 use serde::{Deserialize, Serialize};
 use tokio::{
@@ -52,7 +57,10 @@ pub const DEFAULT_TIMEOUT: Duration = Duration::from_secs(120);
 /// Settings for the remote-command backend (DESIGN.md §10, issue #198).
 ///
 /// The template is not a credential, but it names a host — it arrives from
-/// bootstrap config like the API keys do, never from the database.
+/// bootstrap config like the API keys do, never from the database. The
+/// timeout is the *initial* value only: the running backend re-reads a
+/// shared cell per batch ([`Command::timeout_cell`]), so the operator's edit
+/// of `remote_command_timeout_seconds` applies without a restart (#219).
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct CommandConfig {
     /// The command to run per batch, e.g. `ssh box claude -p`. May carry
@@ -67,6 +75,10 @@ pub struct CommandConfig {
 pub struct Command {
     config: CommandConfig,
     id: BackendId,
+    /// The live per-batch timeout in milliseconds, shared with whoever wired
+    /// this backend to the settings row. Milliseconds so the tests — and an
+    /// impatient operator — can go below one second.
+    timeout_ms: Arc<AtomicU64>,
 }
 
 impl Command {
@@ -83,11 +95,25 @@ impl Command {
             });
         }
         Ok(Self {
+            timeout_ms: Arc::new(AtomicU64::new(
+                u64::try_from(config.timeout.as_millis()).unwrap_or(u64::MAX),
+            )),
             config,
             id: BackendId::new(BACKEND_NAME),
         })
     }
 
+    /// The cell this backend re-reads for every batch, in milliseconds.
+    ///
+    /// Whoever constructs the backend — the daemon, at startup — hands a
+    /// clone of this to the settings API, which stores the row's
+    /// `remote_command_timeout_seconds` into it on every edit. That is the
+    /// path from the database to the running process #219 found missing.
+    #[must_use]
+    pub fn timeout_cell(&self) -> Arc<AtomicU64> {
+        Arc::clone(&self.timeout_ms)
+    }
+
     async fn translate_inner(&self, batch: &Batch) -> Result<Vec<TranslatedCue>> {
         let request_cues: Vec<WireCue> = batch
             .cues
@@ -114,14 +140,17 @@ impl Command {
         }
         let (program, args) = tokens.split_first().expect("the constructor rejects empty");
 
+        // Re-read per call: the settings API writes this cell when the
+        // operator edits `remote_command_timeout_seconds` (#219).
+        let timeout = Duration::from_millis(self.timeout_ms.load(Ordering::Relaxed));
         let work = run(program, args, payload, self.id.clone());
 
         // Dropping `work` on timeout drops the child, whose `kill_on_drop`
         // ends the command — nothing is left resident (DESIGN.md §15).
-        match time::timeout(self.config.timeout, work).await {
+        match time::timeout(timeout, work).await {
             Err(_) => Err(Error::Transport {
                 backend: self.id.clone(),
-                source: format!("timed out after {:?}", self.config.timeout).into(),
+                source: format!("timed out after {timeout:?}").into(),
             }),
             Ok(Err(err)) => Err(err),
             Ok(Ok(out)) => Self::parse_reply(&self.id, &out),

crates/arr-subs/tests/command.rs

@@ -237,4 +237,36 @@ async fn a_hanging_command_is_killed_at_the_timeout() {
     }
 }
 
+/// Issue #219: the timeout is not frozen at construction. The settings API
+/// stores the row's value into [`Command::timeout_cell`] on every edit, and
+/// the next batch must already run under it.
+#[tokio::test]
+async fn an_edited_timeout_reaches_the_next_call() {
+    let dir = tempfile::tempdir().expect("tempdir");
+    let script = stub(dir.path(), "hang.sh", "sleep 30\n");
+    let backend =
+        Command::new(config(&script.display().to_string(), DEFAULT)).expect("backend constructs");
+
+    // The edit that a PUT of remote_command_timeout_seconds performs.
+    backend
+        .timeout_cell()
+        .store(150, std::sync::atomic::Ordering::Relaxed);
+
+    let error = translate(
+        &backend,
+        &cues(&["hello"]),
+        &Language::Other("en".to_owned()),
+        &Language::PortuguesePortugal,
+    )
+    .await
+    .expect_err("the edited timeout must apply without a restart");
+
+    match error {
+        Error::Transport { source, .. } => {
+            assert!(source.to_string().contains("150ms"), "{source}");
+        }
+        other => panic!("expected Transport, got {other:?}"),
+    }
+}
+
 const DEFAULT: Duration = arr_subs::COMMAND_DEFAULT_TIMEOUT;