chore: initial project import

backend/src/Monitor.Backend.Application/Retention/RetentionService.cs

@@ -0,0 +1,77 @@
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+
+namespace Monitor.Backend.Application;
+
+/// <summary>保留清理：原始段文件（持续任务与按需测试保留期不同）、各层指标、事件。保留期来自 settings，可以在线修改。</summary>
+public sealed partial class RetentionService : BackgroundService
+{
+    private static readonly TimeSpan s_interval = TimeSpan.FromHours(1);
+
+    private readonly IRawStore _raw;
+    private readonly IMetricStore _metrics;
+    private readonly IEventStore _events;
+    private readonly IAuthStore _auth;
+    private readonly IHostStore _hosts;
+    private readonly SettingsService _settings;
+    private readonly LoginRateLimiter _limiter;
+    private readonly TimeProvider _time;
+    private readonly ILogger<RetentionService> _logger;
+
+    public RetentionService(IRawStore raw, IMetricStore metrics, IEventStore events, IHostStore hosts, IAuthStore auth, SettingsService settings, LoginRateLimiter limiter, TimeProvider time, ILogger<RetentionService> logger)
+    {
+        _raw = raw;
+        _metrics = metrics;
+        _events = events;
+        _hosts = hosts;
+        _auth = auth;
+        _settings = settings;
+        _limiter = limiter;
+        _time = time;
+        _logger = logger;
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            try
+            {
+                await RunOnceAsync(stoppingToken);
+                await Task.Delay(s_interval, _time, stoppingToken);
+            }
+            catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
+            {
+                return;
+            }
+            catch (Exception ex)
+            {
+                // 后台循环不能因为一次失败而退出
+                LogFailed(ex);
+                await Task.Delay(TimeSpan.FromMinutes(5), _time, stoppingToken);
+            }
+        }
+    }
+
+    /// <summary>执行一轮清理（也供测试直接调用）。</summary>
+    public async Task RunOnceAsync(CancellationToken ct)
+    {
+        DateTimeOffset now = _time.GetUtcNow();
+        long nowMs = now.ToUnixTimeMilliseconds();
+        DateOnly today = DateOnly.FromDateTime(now.UtcDateTime);
+        int rawDays = await _settings.GetIntAsync(SettingsService.RawDays, ct);
+        int testDays = await _settings.GetIntAsync(SettingsService.TestRawDays, ct);
+
+        await _raw.DeleteExpiredAsync(today.AddDays(-rawDays), today.AddDays(-testDays), ct);
+        await _metrics.DeleteOlderThanAsync(MetricLevel.S10, nowMs - (await _settings.GetIntAsync(SettingsService.Metric10sHours, ct) * Steps.Hour), ct);
+        await _metrics.DeleteOlderThanAsync(MetricLevel.M1, nowMs - (await _settings.GetIntAsync(SettingsService.Metric1mDays, ct) * Steps.Day), ct);
+        await _metrics.DeleteOlderThanAsync(MetricLevel.M5, nowMs - (await _settings.GetIntAsync(SettingsService.Metric5mDays, ct) * Steps.Day), ct);
+        await _events.DeleteOlderThanAsync(nowMs - (await _settings.GetIntAsync(SettingsService.EventDays, ct) * Steps.Day), ct);
+        await _hosts.DeleteOlderThanAsync(nowMs - (await _settings.GetIntAsync(SettingsService.HostDays, ct) * Steps.Day), ct);
+        await _auth.DeleteExpiredSessionsAsync(nowMs, ct);
+        _limiter.Prune();
+    }
+
+    [LoggerMessage(Level = LogLevel.Error, Message = "retention pass failed")]
+    private partial void LogFailed(Exception exception);
+}