feat: add scheduled conversation log cleanup via crontab hook

Author: yileicn

src/Infrastructure/BotSharp.OpenAPI/BackgroundServices/ConversationLogCleanupService.cs

@@ -2,6 +2,8 @@
 using BotSharp.Core.MCP.Settings;
 using BotSharp.Core.Users.Services;
 using BotSharp.OpenAPI.BackgroundServices;
+using BotSharp.OpenAPI.Hooks;
+using BotSharp.OpenAPI.RuleTriggers;
 using Microsoft.AspNetCore.Authentication;
 using Microsoft.AspNetCore.Authentication.Cookies;
 using Microsoft.AspNetCore.Authentication.JwtBearer;
@@ -14,6 +16,8 @@
 using Microsoft.Net.Http.Headers;
 using Microsoft.OpenApi;
 using System.Text.Json.Serialization;
+using BotSharp.Abstraction.Crontab;
+
 #if NET8_0
 using Microsoft.OpenApi.Models;
 #endif
@@ -37,7 +41,8 @@ public static IServiceCollection AddBotSharpOpenAPI(this IServiceCollection serv
     {
         services.AddScoped<IUserIdentity, UserIdentity>();
         services.AddHostedService<ConversationTimeoutService>();
-        services.AddHostedService<ConversationLogCleanupService>();
+        
+        services.AddCrontabServices();
 
         // Add bearer authentication
         var schema = "MIXED_SCHEME";
@@ -224,6 +229,13 @@ private static async Task OnTicketReceivedContext(TicketReceivedContext context)
         }
     }
 
+    public static IServiceCollection AddCrontabServices(this IServiceCollection services)
+    {
+        services.AddScoped<ICrontabHook, ConversationLogCleanupCrontabHook>();
+        services.AddScoped<ICrontabSource, ConversationLogCleanupRuleTrigger>();
+        return services;
+    }
+
     /// <summary>
     /// Use Swagger/OpenAPI
     /// </summary>

src/Infrastructure/BotSharp.OpenAPI/BotSharpOpenApiExtensions.cs

@@ -0,0 +1,69 @@
+using BotSharp.Abstraction.Conversations.Settings;
+using BotSharp.Abstraction.Crontab;
+using BotSharp.Abstraction.Crontab.Models;
+using BotSharp.Abstraction.Repositories;
+using BotSharp.OpenAPI.RuleTriggers;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using System;
+using System.Threading.Tasks;
+
+namespace BotSharp.OpenAPI.Hooks
+{
+    public class ConversationLogCleanupCrontabHook : ICrontabHook
+    {
+        private readonly ConversationSetting _settings;
+        private readonly IBotSharpRepository _db;
+        private readonly ILogger<ConversationLogCleanupCrontabHook> _logger;
+        private readonly IHostApplicationLifetime _appLifetime;
+        
+        public string[]? Triggers => new[] { nameof(ConversationLogCleanupRuleTrigger) };
+
+        public ConversationLogCleanupCrontabHook(
+            ConversationSetting settings,
+            IBotSharpRepository db,
+            ILogger<ConversationLogCleanupCrontabHook> logger,
+            IHostApplicationLifetime appLifetime)
+        {
+            _settings = settings;
+            _db = db;
+            _logger = logger;
+            _appLifetime = appLifetime;
+        }
+
+        public async Task OnCronTriggered(CrontabItem item)
+        {
+            var cleanSetting = _settings.CleanSetting;
+
+            if (cleanSetting == null || !cleanSetting.Enable || cleanSetting.LogRetentionDays <= 0) return;
+
+            int totalDeleted = 0;
+            var cancellationToken = _appLifetime.ApplicationStopping;
+            
+            while (!cancellationToken.IsCancellationRequested)
+            {
+                var deletedCount = await _db.DeleteOldConversationLogs(cleanSetting.LogRetentionDays, cleanSetting.LogBatchSize);
+                if (deletedCount == 0) break;
+                
+                totalDeleted += deletedCount;
+                _logger.LogInformation($"Cleaned {deletedCount} conversation logs older than {cleanSetting.LogRetentionDays} days in this batch.");
+                
+                try
+                {
+                    // Sleep slightly to yield database resources, will throw TaskCanceledException on shutdown
+                    await Task.Delay(1000, cancellationToken);
+                }
+                catch (OperationCanceledException)
+                {
+                    _logger.LogWarning("Conversation log cleanup was interrupted due to application shutdown.");
+                    break;
+                }
+            }
+
+            if (totalDeleted > 0)
+            {
+                _logger.LogInformation($"Successfully cleaned a total of {totalDeleted} conversation logs older than {cleanSetting.LogRetentionDays} days.");
+            }
+        }
+    }
+}

src/Infrastructure/BotSharp.OpenAPI/Hooks/ConversationLogCleanupCrontabHook.cs

@@ -0,0 +1,26 @@
+using BotSharp.Abstraction.Conversations.Enums;
+using BotSharp.Abstraction.Crontab;
+using BotSharp.Abstraction.Crontab.Models;
+using BotSharp.Abstraction.Rules;
+
+namespace BotSharp.OpenAPI.RuleTriggers
+{
+    public class ConversationLogCleanupRuleTrigger : IRuleTrigger, ICrontabSource
+    {
+        public string Channel => ConversationChannel.Crontab;
+        public string Name => nameof(ConversationLogCleanupRuleTrigger);
+        public string EntityType { get; set; } = string.Empty;
+        public string EntityId { get; set; } = string.Empty;
+
+        public CrontabItem GetCrontabItem()
+        {
+            return new CrontabItem
+            {
+                Title = nameof(ConversationLogCleanupRuleTrigger),
+                Description = "Clean up old conversation logs daily",
+                Cron = "0 6 * * *", // Run at 6:00 AM UTC (Midnight Chicago Standard Time)
+                TriggerType = CronTabItemTriggerType.MessageQueue
+            };
+        }
+    }
+}