fix(drivers): wire PollGroupEngine onError->health + 30s poll backoff (05/STAB-9) [modbus,abcip,ablegacy]

2026-07-13 11:57:25 -04:00
parent ca6530c7f5
commit 9213c037b0
7 changed files with 239 additions and 4 deletions
@@ -118,7 +118,26 @@ public sealed class ModbusDriver
            {
                if (!ShouldPublish(tagRef, snapshot)) return;
                OnDataChange?.Invoke(this, new DataChangeEventArgs(handle, tagRef, snapshot));
-            });
+            },
+            onError: HandlePollError,
+            backoffCap: PollBackoffCap);
+    }
+
+    /// <summary>Upper bound on the poll-loop failure backoff — adopts the S7-proven 30 s cap fleet-wide (05/STAB-8).</summary>
+    private static readonly TimeSpan PollBackoffCap = TimeSpan.FromSeconds(30);
+
+    /// <summary>
+    ///     05/STAB-9 — routes a poll-loop reader failure to the driver health surface: logs it and
+    ///     degrades to <see cref="DriverState.Degraded"/> preserving <c>LastSuccessfulRead</c>.
+    ///     Never downgrades a <see cref="DriverState.Faulted"/> state (a stronger, config-level signal).
+    /// </summary>
+    /// <param name="ex">The exception caught by the poll engine.</param>
+    internal void HandlePollError(Exception ex)
+    {
+        _logger.LogWarning(ex, "Modbus poll reader failed. Driver={DriverInstanceId}", _driverInstanceId);
+        var current = ReadHealth();
+        if (current.State != DriverState.Faulted)
+            WriteHealth(new DriverHealth(DriverState.Degraded, current.LastSuccessfulRead, ex.Message));
    }

    /// <inheritdoc />