fix(deployment): purge SystemArtifactDeploymentRecords in the terminal-record retention sweep (review 2026-10-21 08/G2)

docs/requirements/Component-DeploymentManager.md

@@ -221,6 +221,11 @@ never purged regardless of age: it is precisely the row the query-before-redeplo
 reconciliation reads to decide whether a prior deploy actually landed at the site,
 and expiring it by age would silently disable that idempotency guard.
 
+The same window also bounds **`SystemArtifactDeploymentRecords`** — one row per
+*Deploy Artifacts* run, written after the sweep and never read back — which the
+sweep deletes by `DeployedAt` in the same bounded batches. Before 2026-10 that table
+had no purge path at all.
+
 ## Diff View
 
 Before deploying, the Deployment Manager can request a diff from the Template Engine showing:

src/ZB.MOM.WW.ScadaBridge.Commons/Interfaces/Repositories/IDeploymentManagerRepository.cs

@@ -194,6 +194,17 @@ public interface IDeploymentManagerRepository
     /// <param name="cancellationToken">A cancellation token that can be used to cancel the operation.</param>
     /// <returns>A task representing the asynchronous operation.</returns>
     Task DeleteSystemArtifactDeploymentAsync(int id, CancellationToken cancellationToken = default);
+    /// <summary>
+    /// Deletes system artifact deployment records deployed before <paramref name="cutoffUtc"/>,
+    /// in one bounded batch. One row is written per <i>Deploy Artifacts</i> run and nothing
+    /// reads them back, so they share the terminal deployment-record retention window
+    /// instead of growing without bound.
+    /// </summary>
+    /// <param name="cutoffUtc">Records deployed before this instant are eligible.</param>
+    /// <param name="batchSize">Maximum rows deleted in this call.</param>
+    /// <param name="cancellationToken">A cancellation token that can be used to cancel the operation.</param>
+    /// <returns>The number of rows deleted; fewer than <paramref name="batchSize"/> means the sweep is complete.</returns>
+    Task<int> PurgeSystemArtifactDeploymentRecordsAsync(DateTimeOffset cutoffUtc, int batchSize, CancellationToken cancellationToken = default);
 
     // DeployedConfigSnapshot
     /// <summary>

src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/Repositories/DeploymentManagerRepository.cs

@@ -285,6 +285,29 @@ public class DeploymentManagerRepository : IDeploymentManagerRepository
         return Task.CompletedTask;
     }
 
+    /// <inheritdoc />
+    public async Task<int> PurgeSystemArtifactDeploymentRecordsAsync(
+        DateTimeOffset cutoffUtc,
+        int batchSize,
+        CancellationToken cancellationToken = default)
+    {
+        // Same bounded-batch shape as PurgeTerminalDeploymentRecordsAsync: the caller
+        // re-invokes until fewer than batchSize rows come back. Every row is terminal by
+        // construction (it is written once, after the artifact sweep finished).
+        var stale = await _dbContext.SystemArtifactDeploymentRecords
+            .Where(d => d.DeployedAt < cutoffUtc)
+            .OrderBy(d => d.Id)
+            .Take(batchSize)
+            .ToListAsync(cancellationToken);
+
+        if (stale.Count == 0)
+            return 0;
+
+        _dbContext.SystemArtifactDeploymentRecords.RemoveRange(stale);
+        await _dbContext.SaveChangesAsync(cancellationToken);
+        return stale.Count;
+    }
+
     // --- DeployedConfigSnapshot ---
 
     /// <inheritdoc />

src/ZB.MOM.WW.ScadaBridge.DeploymentManager/DeploymentManagerOptions.cs

@@ -72,6 +72,8 @@ public class DeploymentManagerOptions
     /// <c>InProgress</c> or <c>Pending</c> row is never purged regardless of age,
     /// because it is exactly the row the query-before-redeploy reconciliation
     /// path needs to find. Set to <see cref="TimeSpan.Zero"/> to disable purging.
+    /// The same window bounds system artifact deployment records (one per
+    /// <i>Deploy Artifacts</i> run), purged by their deploy time.
     /// </para>
     /// </summary>
     public TimeSpan TerminalDeploymentRecordRetention { get; set; } = TimeSpan.FromDays(365);

src/ZB.MOM.WW.ScadaBridge.DeploymentManager/DeploymentService.cs

@@ -1330,7 +1330,8 @@ public class DeploymentService
                 instanceId, uniqueName, deploymentId, false, result.Error);
 
     /// <summary>
-    /// Opportunistic retention sweep for TERMINAL deployment records, rate-limited
+    /// Opportunistic retention sweep for TERMINAL deployment records and system
+    /// artifact deployment records, rate-limited
     /// to once every <see cref="TerminalPurgeMinInterval"/> per process and bounded
     /// to <see cref="TerminalPurgeBatchesPerSweep"/> batches per call.
     ///
@@ -1379,12 +1380,26 @@ public class DeploymentService
                     break;
             }
 
+            // System artifact deployment records (one per Deploy Artifacts run) share the
+            // same retention window — nothing reads them back, so without this sweep the
+            // table only ever grows.
+            var artifactPurged = 0;
+            for (var batch = 0; batch < TerminalPurgeBatchesPerSweep; batch++)
+            {
+                var deleted = await _repository.PurgeSystemArtifactDeploymentRecordsAsync(
+                    cutoff, TerminalPurgeBatchSize, cancellationToken);
+                artifactPurged += deleted;
+                if (deleted < TerminalPurgeBatchSize)
+                    break;
+            }
+
+            purged += artifactPurged;
             if (purged > 0)
             {
                 _logger.LogInformation(
-                    "Purged {Count} terminal deployment record(s) completed before {Cutoff} " +
-                    "(retention {Retention}).",
-                    purged, cutoff, retention);
+                    "Purged {Count} terminal deployment record(s) ({ArtifactCount} system artifact " +
+                    "record(s)) completed before {Cutoff} (retention {Retention}).",
+                    purged, artifactPurged, cutoff, retention);
             }
         }
         catch (Exception ex)

tests/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Tests/SystemArtifactDeploymentPurgeTests.cs

@@ -0,0 +1,52 @@
+using ZB.MOM.WW.ScadaBridge.Commons.Entities.Deployment;
+using ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Repositories;
+
+namespace ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Tests;
+
+/// <summary>
+/// Retention purge for <see cref="SystemArtifactDeploymentRecord"/> rows (review 2026-10-21
+/// 08/G2): one row is written per Deploy Artifacts run and nothing reads them back, so they
+/// must share the terminal deployment-record retention window.
+/// </summary>
+public sealed class SystemArtifactDeploymentPurgeTests : IDisposable
+{
+    private readonly ScadaBridgeDbContext _context = SqliteTestHelper.CreateInMemoryContext();
+    private readonly DeploymentManagerRepository _repository;
+
+    /// <summary>Initializes the repository over a fresh in-memory SQLite context.</summary>
+    public SystemArtifactDeploymentPurgeTests()
+    {
+        _repository = new DeploymentManagerRepository(_context);
+    }
+
+    /// <summary>Releases the in-memory database.</summary>
+    public void Dispose() => _context.Dispose();
+
+    private async Task SeedAsync(DateTimeOffset deployedAt)
+    {
+        await _repository.AddSystemArtifactDeploymentAsync(
+            new SystemArtifactDeploymentRecord("Artifacts", "admin") { DeployedAt = deployedAt });
+        await _repository.SaveChangesAsync();
+    }
+
+    /// <summary>Only rows older than the cutoff are deleted, in bounded batches.</summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task Purge_DeletesOnlyRowsOlderThanCutoff_InBoundedBatches()
+    {
+        var now = DateTimeOffset.UtcNow;
+        await SeedAsync(now.AddDays(-400));
+        await SeedAsync(now.AddDays(-380));
+        await SeedAsync(now.AddDays(-370));
+        await SeedAsync(now.AddDays(-1));
+        var cutoff = now.AddDays(-365);
+
+        Assert.Equal(2, await _repository.PurgeSystemArtifactDeploymentRecordsAsync(cutoff, batchSize: 2));
+        Assert.Equal(1, await _repository.PurgeSystemArtifactDeploymentRecordsAsync(cutoff, batchSize: 2));
+        Assert.Equal(0, await _repository.PurgeSystemArtifactDeploymentRecordsAsync(cutoff, batchSize: 2));
+
+        var remaining = await _repository.GetAllSystemArtifactDeploymentsAsync();
+        var survivor = Assert.Single(remaining);
+        Assert.True(survivor.DeployedAt > cutoff);
+    }
+}

tests/ZB.MOM.WW.ScadaBridge.DeploymentManager.Tests/DeploymentServiceTests.cs

@@ -87,6 +87,32 @@ public class DeploymentServiceTests : TestKit
             PendingDeploymentTtl = TestPendingTtl
         });
 
+    // ── Terminal-record retention (review 2026-10-21 08/G2) ──
+
+    /// <summary>
+    /// The retention sweep also purges system artifact deployment records — one per Deploy
+    /// Artifacts run, never read back — with the same cutoff as terminal deployment records.
+    /// NOTE: the sweep is rate-limited by a process-wide static, so this is the only test in
+    /// the assembly that may drive <see cref="DeploymentService.TryPurgeTerminalDeploymentRecordsAsync"/>.
+    /// </summary>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    [Fact]
+    public async Task TryPurgeTerminalDeploymentRecords_AlsoPurgesSystemArtifactRecords()
+    {
+        _repo.PurgeTerminalDeploymentRecordsAsync(Arg.Any<DateTimeOffset>(), Arg.Any<int>(), Arg.Any<CancellationToken>())
+            .Returns(1);
+        _repo.PurgeSystemArtifactDeploymentRecordsAsync(Arg.Any<DateTimeOffset>(), Arg.Any<int>(), Arg.Any<CancellationToken>())
+            .Returns(3);
+
+        var purged = await _service.TryPurgeTerminalDeploymentRecordsAsync();
+
+        Assert.Equal(4, purged);
+        var expectedCutoff = DateTimeOffset.UtcNow - new DeploymentManagerOptions().TerminalDeploymentRecordRetention;
+        await _repo.Received(1).PurgeSystemArtifactDeploymentRecordsAsync(
+            Arg.Is<DateTimeOffset>(c => (c - expectedCutoff).Duration() < TimeSpan.FromMinutes(1)),
+            Arg.Any<int>(), Arg.Any<CancellationToken>());
+    }
+
     // ── Deployment flow ──
 
     /// <summary>Verifies that deploy instance async instance not found returns failure.</summary>