Init Crontab

src/Infrastructure/BotSharp.Abstraction/Agents/Enums/BuiltInAgentId.cs

@@ -56,4 +56,9 @@ public class BuiltInAgentId
     /// Translates user-defined natural language rules into programmatic code
     /// </summary>
     public const string RuleEncoder = "6acfb93c-3412-402e-9ba5-c5d3cd8f0161";
+
+    /// <summary>
+    /// Schedule job
+    /// </summary>
+    public const string Crontab = "c2o139da-a62a-4355-8605-fdf0ffaca58e";
 }

src/Infrastructure/BotSharp.Abstraction/Conversations/Enums/ConversationChannel.cs

@@ -7,4 +7,5 @@ public class ConversationChannel
     public const string Phone = "phone";
     public const string Messenger = "messenger";
     public const string Email = "email";
+    public const string Cron = "cron";
 }

src/Infrastructure/BotSharp.Abstraction/Infrastructures/IDistributedLocker.cs

@@ -0,0 +1,7 @@
+namespace BotSharp.Abstraction.Infrastructures;
+
+public interface IDistributedLocker
+{
+    bool Lock(string resource, Action action, int timeout = 30);
+    Task<bool> LockAsync(string resource, Func<Task> action, int timeout = 30);
+}

src/Infrastructure/BotSharp.Core.Crontab/Abstraction/ICrontabHook.cs

@@ -0,0 +1,8 @@
+using BotSharp.Core.Crontab.Models;
+
+namespace BotSharp.Core.Crontab.Abstraction;
+
+public interface ICrontabHook
+{
+    Task OnCronTriggered(CrontabItem item);
+}

src/Infrastructure/BotSharp.Core.Crontab/Abstraction/ICrontabService.cs

@@ -0,0 +1,9 @@
+using BotSharp.Core.Crontab.Models;
+
+namespace BotSharp.Core.Crontab.Abstraction;
+
+public interface ICrontabService
+{
+    Task<List<CrontabItem>> GetCrontable();
+    Task ScheduledTimeArrived(CrontabItem item);
+}

src/Infrastructure/BotSharp.Core.Crontab/BotSharp.Core.Crontab.csproj

@@ -0,0 +1,28 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <None Remove="data\agents\c2o139da-a62a-4355-8605-fdf0ffaca58e\agent.json" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Content Include="data\agents\c2o139da-a62a-4355-8605-fdf0ffaca58e\agent.json">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\BotSharp.Abstraction\BotSharp.Abstraction.csproj" />
+    <ProjectReference Include="..\BotSharp.Core\BotSharp.Core.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="NCrontab" Version="3.3.3" />
+  </ItemGroup>
+
+</Project>

src/Infrastructure/BotSharp.Core.Crontab/CrontabPlugin.cs

@@ -0,0 +1,40 @@
+/*****************************************************************************
+  Copyright 2024 Written by Haiping Chen. All Rights Reserved.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+******************************************************************************/
+
+namespace BotSharp.Core.Crontab;
+
+/// <summary>
+///  Crontab plugin is a time-based job scheduler in agent framework. 
+///  The cron system is used for automating repetitive tasks, such as trigger AI Agent to do specific task periodically.
+/// </summary>
+public class CrontabPlugin : IBotSharpPlugin
+{
+    public string Id => "3155c15e-28d3-43f7-8ead-fc43324ec21a";
+    public string Name => "BotSharp Crontab";
+    public string Description => "Crontab plugin is a time-based job scheduler in agent framework. The cron system is used to trigger AI Agent to do specific task periodically.";
+    public string IconUrl => "https://icon-library.com/images/stop-watch-icon/stop-watch-icon-10.jpg";
+
+    public string[] AgentIds =
+    [
+        BuiltInAgentId.Crontab
+    ];
+
+    public void RegisterDI(IServiceCollection services, IConfiguration config)
+    {
+        services.AddScoped<ICrontabService, CrontabService>();
+        services.AddHostedService<CrontabWatcher>();
+    }
+}

src/Infrastructure/BotSharp.Core.Crontab/Models/CrontabItem.cs

@@ -0,0 +1,14 @@
+namespace BotSharp.Core.Crontab.Models;
+
+public class CrontabItem
+{
+    public string UserId { get; set; } = null!;
+    public string AgentId { get; set; } = null!;
+    public string Topic { get; set; } = null!;
+    public string Cron { get; set; } = null!;
+
+    public override string ToString()
+    {
+        return $"AgentId: {AgentId}, UserId: {UserId}, Topic: {Topic}";
+    }
+}

src/Infrastructure/BotSharp.Core.Crontab/Services/CrontabService.cs

@@ -0,0 +1,77 @@
+/*****************************************************************************
+  Copyright 2024 Written by Haiping Chen. All Rights Reserved.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+******************************************************************************/
+
+using BotSharp.Abstraction.Agents.Enums;
+using BotSharp.Core.Crontab.Models;
+using BotSharp.Core.Infrastructures;
+
+
+/*****************************************************************************
+  Copyright 2024 Written by Haiping Chen. All Rights Reserved.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+******************************************************************************/
+
+using Microsoft.Extensions.Logging;
+
+namespace BotSharp.Core.Crontab.Services;
+
+/// <summary>
+/// The Crontab service schedules distributed events based on the execution times provided by users. 
+/// In a scalable environment, distributed locks are used to ensure that each event is triggered only once.
+/// </summary>
+public class CrontabService : ICrontabService
+{
+    private readonly IServiceProvider _services;
+    private ILogger _logger;
+
+    public CrontabService(IServiceProvider services, ILogger<CrontabService> logger)
+    {
+        _services = services;
+        _logger = logger;
+    }
+
+    public async Task<List<CrontabItem>> GetCrontable()
+    {
+        return 
+        [
+            new CrontabItem 
+            {
+                Cron = "*/30 * * * * *",
+                AgentId = BuiltInAgentId.AIAssistant,
+            }
+        ];
+    }
+
+    public async Task ScheduledTimeArrived(CrontabItem item)
+    {
+        _logger.LogInformation("ScheduledTimeArrived");
+        await HookEmitter.Emit<ICrontabHook>(_services, async hook =>
+            await hook.OnCronTriggered(item)
+        );
+        await Task.Delay(1000 * 10);
+    }
+}

src/Infrastructure/BotSharp.Core.Crontab/Services/CrontabWatcher.cs

@@ -0,0 +1,70 @@
+using BotSharp.Abstraction.Infrastructures;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using NCrontab;
+
+namespace BotSharp.Core.Crontab.Services;
+
+public class CrontabWatcher : BackgroundService
+{
+    private readonly ILogger _logger;
+    private readonly IServiceProvider _services;
+
+    public CrontabWatcher(IServiceProvider services, ILogger<CrontabWatcher> logger)
+    {
+        _logger = logger;
+        _services = services;
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        _logger.LogInformation("Crontab Watcher background service is running.");
+
+        using (var scope = _services.CreateScope())
+        {
+            var locker = scope.ServiceProvider.GetRequiredService<IDistributedLocker>();
+
+            while (!stoppingToken.IsCancellationRequested)
+            {
+                var delay = Task.Delay(1000, stoppingToken);
+
+                await locker.LockAsync("CrontabWatcher", async () =>
+                {
+                    await RunCronChecker(scope.ServiceProvider);
+                });
+
+                await delay;
+            }
+
+            _logger.LogWarning("Crontab Watcher background service is stopped.");
+        }
+    }
+
+    private async Task RunCronChecker(IServiceProvider services)
+    {
+        var cron = services.GetRequiredService<ICrontabService>();
+        var crons = await cron.GetCrontable();
+        foreach (var item in crons)
+        {
+            var schedule = CrontabSchedule.Parse(item.Cron, new CrontabSchedule.ParseOptions
+            {
+                IncludingSeconds = true // Ensure you account for seconds
+            });
+
+            // Get the current time
+            var currentTime = DateTime.UtcNow;
+
+            // Get the next occurrence from the schedule
+            var nextOccurrence = schedule.GetNextOccurrence(currentTime.AddSeconds(-1));
+
+            // Check if the current time matches the schedule
+            bool matches = currentTime >= nextOccurrence && currentTime < nextOccurrence.AddSeconds(1);
+
+            if (matches)
+            {
+                _logger.LogInformation($"The current time matches the cron expression {item}");
+                cron.ScheduledTimeArrived(item);
+            }
+        }
+    }
+}

src/Infrastructure/BotSharp.Core.Crontab/Using.cs

@@ -0,0 +1,7 @@
+global using Microsoft.Extensions.Configuration;
+global using Microsoft.Extensions.DependencyInjection;
+
+global using BotSharp.Abstraction.Agents.Enums;
+global using BotSharp.Abstraction.Plugins;
+global using BotSharp.Core.Crontab.Services;
+global using BotSharp.Core.Crontab.Abstraction;

src/Infrastructure/BotSharp.Core.Crontab/data/agents/c2o139da-a62a-4355-8605-fdf0ffaca58e/agent.json

@@ -0,0 +1,24 @@
+{
+  "id": "c2o139da-a62a-4355-8605-fdf0ffaca58e",
+  "name": "Crontab",
+  "description": "Convert the user-specified schedule into a Cron expression, accurate to the second level.",
+  "iconUrl": "https://icon-library.com/images/stop-watch-icon/stop-watch-icon-10.jpg",
+  "type": "task",
+  "createdDateTime": "2024-12-03T00:00:00Z",
+  "updatedDateTime": "2024-12-03T00:00:00Z",
+  "disabled": false,
+  "isPublic": true,
+  "profiles": [ "cron" ],
+  "llmConfig": {
+    "provider": "openai",
+    "model": "gpt-4o-mini"
+  },
+  "routingRules": [
+    {
+      "field": "cron_expression",
+      "required": true,
+      "field_type": "string",
+      "description": "A Cron expression, accurate to the second level."
+    }
+  ]
+}

src/Infrastructure/BotSharp.Core/BotSharpCoreExtensions.cs

@@ -25,7 +25,7 @@ public static class BotSharpCoreExtensions
         config.Bind("Interpreter", interpreterSettings);
         services.AddSingleton(x => interpreterSettings);
 
-        services.AddSingleton<DistributedLocker>();
+        services.AddSingleton<IDistributedLocker, DistributedLocker>();
         // Register template render
         services.AddSingleton<ITemplateRender, TemplateRender>();
 

src/Infrastructure/BotSharp.Core/Infrastructures/DistributedLocker.cs

@@ -1,9 +1,10 @@
+using BotSharp.Abstraction.Infrastructures;
 using Medallion.Threading.Redis;
 using StackExchange.Redis;
 
 namespace BotSharp.Core.Infrastructures;
 
-public class DistributedLocker
+public class DistributedLocker : IDistributedLocker
 {
     private readonly IConnectionMultiplexer _redis;
     private readonly ILogger _logger;
@@ -14,7 +15,7 @@ public class DistributedLocker
         _logger = logger;
     }
 
-    public async Task<T> Lock<T>(string resource, Func<Task<T>> action, int timeoutInSeconds = 30)
+    public async Task<bool> LockAsync(string resource, Func<Task> action, int timeoutInSeconds = 30)
     {
         var timeout = TimeSpan.FromSeconds(timeoutInSeconds);
 
@@ -24,9 +25,11 @@ public class DistributedLocker
             if (handle == null) 
             {
                 _logger.LogWarning($"Acquire lock for {resource} failed due to after {timeout}s timeout.");
+                return false;
             }
             
-            return await action();
+            await action();
+            return true;
         }
     }