version-0.1 (#1)

Squash and merge of version-0.1

Co-authored-by: James Wampler <james@wamp.dev>
Co-committed-by: James Wampler <james@wamp.dev>

src/api/MicCheck.Api/Features/FeatureUsageFlushBackgroundService.cs

@@ -0,0 +1,60 @@
+using MicCheck.Api.Data;
+using Microsoft.EntityFrameworkCore;
+
+namespace MicCheck.Api.Features;
+
+public class FeatureUsageFlushBackgroundService(
+    FeatureUsageMetrics metrics,
+    IServiceScopeFactory scopeFactory,
+    ILogger<FeatureUsageFlushBackgroundService> logger) : BackgroundService
+{
+    private static readonly TimeSpan FlushInterval = TimeSpan.FromSeconds(30);
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        using var timer = new PeriodicTimer(FlushInterval);
+        while (await timer.WaitForNextTickAsync(stoppingToken))
+        {
+            await FlushAsync(stoppingToken);
+        }
+    }
+
+    public override async Task StopAsync(CancellationToken cancellationToken)
+    {
+        await base.StopAsync(cancellationToken);
+        await FlushAsync(CancellationToken.None);
+    }
+
+    private async Task FlushAsync(CancellationToken ct)
+    {
+        var deltas = metrics.DrainAccumulated();
+        if (deltas.Count == 0)
+            return;
+
+        var updatedAt = DateTimeOffset.UtcNow;
+
+        try
+        {
+            await using var scope = scopeFactory.CreateAsyncScope();
+            var db = scope.ServiceProvider.GetRequiredService<MicCheckDbContext>();
+
+            foreach (var (key, count) in deltas)
+            {
+                await db.Database.ExecuteSqlAsync(
+                    $"""
+                    INSERT INTO "FeatureUsageDaily" ("EnvironmentId", "FeatureId", "FeatureName", "UsageDate", "Count", "UpdatedAt")
+                    VALUES ({key.EnvironmentId}, {key.FeatureId}, {key.FeatureName}, {key.UsageDate}, {count}, {updatedAt})
+                    ON CONFLICT ("EnvironmentId", "FeatureId", "UsageDate")
+                    DO UPDATE SET "Count" = "FeatureUsageDaily"."Count" + EXCLUDED."Count",
+                                  "FeatureName" = EXCLUDED."FeatureName",
+                                  "UpdatedAt" = EXCLUDED."UpdatedAt"
+                    """,
+                    ct);
+            }
+        }
+        catch (Exception ex)
+        {
+            logger.LogError(ex, "Failed to flush feature usage data ({BucketCount} buckets)", deltas.Count);
+        }
+    }
+}