feat(site): older-write guard for replicated config writes

Add StoreDeployedConfigIfNewerAsync to SiteStorageService — an atomic conditional upsert using SQLite's ON CONFLICT … WHERE clause so the standby node only overwrites a deployed_configurations row when the incoming deployed_at is strictly newer. The active-node path (StoreDeployedConfigAsync) stays unguarded. Four deterministic tests cover: no-row insert, older-overwrites, newer-is-noop, equal-is-noop; all seed rows with explicit DateTimeOffset values via direct SQL to avoid wall-clock timing dependencies.
2026-06-26 13:29:21 -04:00
parent 7a085444e4
commit caaa855362
2 changed files with 174 additions and 0 deletions
@@ -1,3 +1,4 @@
+using Microsoft.Data.Sqlite;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
 using ZB.MOM.WW.ScadaBridge.SiteRuntime.Persistence;
@@ -194,4 +195,112 @@ public class SiteStorageServiceTests : IAsyncLifetime, IDisposable
        Assert.Empty(configs);
        Assert.Empty(overrides);
    }
+
+    // ── Task 13: StoreDeployedConfigIfNewerAsync (guarded standby write) ──
+
+    /// <summary>
+    /// Seeds a deployed_configurations row with an explicit deployed_at timestamp using the same
+    /// "O" format the service uses, so tests can establish deterministic older/newer/equal rows.
+    /// </summary>
+    private async Task SeedDeployedConfigAsync(
+        string instanceName, string configJson, string deploymentId,
+        string revisionHash, bool isEnabled, DateTimeOffset deployedAt)
+    {
+        await using var conn = new SqliteConnection($"Data Source={_dbFile}");
+        await conn.OpenAsync();
+        await using var cmd = conn.CreateCommand();
+        cmd.CommandText = @"
+            INSERT INTO deployed_configurations
+                (instance_unique_name, config_json, deployment_id, revision_hash, is_enabled, deployed_at)
+            VALUES (@name, @json, @depId, @hash, @enabled, @deployedAt)
+            ON CONFLICT(instance_unique_name) DO UPDATE SET
+                config_json   = excluded.config_json,
+                deployment_id = excluded.deployment_id,
+                revision_hash = excluded.revision_hash,
+                is_enabled    = excluded.is_enabled,
+                deployed_at   = excluded.deployed_at";
+        cmd.Parameters.AddWithValue("@name", instanceName);
+        cmd.Parameters.AddWithValue("@json", configJson);
+        cmd.Parameters.AddWithValue("@depId", deploymentId);
+        cmd.Parameters.AddWithValue("@hash", revisionHash);
+        cmd.Parameters.AddWithValue("@enabled", isEnabled ? 1 : 0);
+        cmd.Parameters.AddWithValue("@deployedAt", deployedAt.ToString("O"));
+        await cmd.ExecuteNonQueryAsync();
+    }
+
+    [Fact]
+    public async Task StoreDeployedConfigIfNewer_NoExistingRow_Inserts()
+    {
+        var at = DateTimeOffset.UtcNow;
+
+        await _storage.StoreDeployedConfigIfNewerAsync(
+            "Pump1", "{\"v\":1}", "dep-001", "sha256:aaa", isEnabled: true, deployedAtOverride: at);
+
+        var configs = await _storage.GetAllDeployedConfigsAsync();
+        Assert.Single(configs);
+        Assert.Equal("Pump1", configs[0].InstanceUniqueName);
+        Assert.Equal("{\"v\":1}", configs[0].ConfigJson);
+        Assert.Equal("dep-001", configs[0].DeploymentId);
+        Assert.Equal("sha256:aaa", configs[0].RevisionHash);
+        Assert.True(configs[0].IsEnabled);
+    }
+
+    [Fact]
+    public async Task StoreDeployedConfigIfNewer_ExistingOlderRow_Overwrites()
+    {
+        var olderAt = new DateTimeOffset(2026, 1, 1, 10, 0, 0, TimeSpan.Zero);
+        var newerAt = new DateTimeOffset(2026, 1, 1, 11, 0, 0, TimeSpan.Zero);
+
+        await SeedDeployedConfigAsync("Pump1", "{\"v\":1}", "dep-001", "sha256:aaa", true, olderAt);
+
+        await _storage.StoreDeployedConfigIfNewerAsync(
+            "Pump1", "{\"v\":2}", "dep-002", "sha256:bbb", isEnabled: false, deployedAtOverride: newerAt);
+
+        var configs = await _storage.GetAllDeployedConfigsAsync();
+        Assert.Single(configs);
+        Assert.Equal("{\"v\":2}", configs[0].ConfigJson);
+        Assert.Equal("dep-002", configs[0].DeploymentId);
+        Assert.Equal("sha256:bbb", configs[0].RevisionHash);
+        Assert.False(configs[0].IsEnabled);
+    }
+
+    [Fact]
+    public async Task StoreDeployedConfigIfNewer_ExistingNewerRow_IsNoop()
+    {
+        var newerAt = new DateTimeOffset(2026, 6, 1, 12, 0, 0, TimeSpan.Zero);
+        var olderAt = new DateTimeOffset(2026, 5, 1, 12, 0, 0, TimeSpan.Zero);
+
+        // Seed the row that is already newer than what the standby would write
+        await SeedDeployedConfigAsync("Pump1", "{\"v\":2}", "dep-002", "sha256:bbb", false, newerAt);
+
+        // Guarded write with an older timestamp — must be a NO-OP
+        await _storage.StoreDeployedConfigIfNewerAsync(
+            "Pump1", "{\"v\":1}", "dep-001", "sha256:aaa", isEnabled: true, deployedAtOverride: olderAt);
+
+        var configs = await _storage.GetAllDeployedConfigsAsync();
+        Assert.Single(configs);
+        // The newer seeded row must survive unchanged
+        Assert.Equal("{\"v\":2}", configs[0].ConfigJson);
+        Assert.Equal("dep-002", configs[0].DeploymentId);
+        Assert.Equal("sha256:bbb", configs[0].RevisionHash);
+        Assert.False(configs[0].IsEnabled);
+    }
+
+    [Fact]
+    public async Task StoreDeployedConfigIfNewer_EqualDeployedAt_IsNoop()
+    {
+        var at = new DateTimeOffset(2026, 3, 15, 9, 30, 0, TimeSpan.Zero);
+
+        await SeedDeployedConfigAsync("Pump1", "{\"v\":1}", "dep-001", "sha256:aaa", true, at);
+
+        // Guarded write with the IDENTICAL timestamp — must be a NO-OP (> not >=)
+        await _storage.StoreDeployedConfigIfNewerAsync(
+            "Pump1", "{\"v\":2}", "dep-002", "sha256:bbb", isEnabled: false, deployedAtOverride: at);
+
+        var configs = await _storage.GetAllDeployedConfigsAsync();
+        Assert.Single(configs);
+        // Original row preserved
+        Assert.Equal("{\"v\":1}", configs[0].ConfigJson);
+        Assert.Equal("dep-001", configs[0].DeploymentId);
+    }
 }