feat(dcl): bound per-tag seed ReadAsync with SeedReadTimeout (#232, DCL-027)

2026-06-19 01:35:40 -04:00
parent b432c788c3
commit 7c1d61647e
11 changed files with 36 additions and 9 deletions
@@ -780,9 +780,16 @@ public class DataConnectionActor : UntypedActor, IWithStash, IWithTimers
        {
            foreach (var tagPath in pending.ToList())
            {
+                // DataConnectionLayer-027: bound each per-tag read with SeedReadTimeout so a
+                // hung device read cannot delay SubscribeCompleted/the ack indefinitely.
+                // On timeout the catch block treats it identically to any other failed seed
+                // read — the tag stays in pending, is retried up to SeedReadMaxAttempts, and
+                // left Uncertain if still empty after the budget. Same CancellationTokenSource
+                // mechanism used by HandleWrite for WriteTimeout (DataConnectionLayer-005).
+                using var cts = new CancellationTokenSource(_options.SeedReadTimeout);
                try
                {
-                    var readResult = await adapter.ReadAsync(tagPath);
+                    var readResult = await adapter.ReadAsync(tagPath, cts.Token);
                    if (readResult.Success && readResult.Value is { Value: not null } value)
                    {
                        seedValues.Add(new SeededValue(tagPath, value));
@@ -792,6 +799,7 @@ public class DataConnectionActor : UntypedActor, IWithStash, IWithTimers
                catch
                {
                    // Best-effort read — retried below, or logged once the budget is spent.
+                    // Includes OperationCanceledException on SeedReadTimeout expiry.
                }
            }