Conversation rate limit.

src/Infrastructure/BotSharp.Abstraction/Conversations/Models/Conversation.cs

@@ -51,6 +51,11 @@ public class DialogElement
         Content = content;
         RichContent = richContent;
     }
+
+    public override string ToString()
+    {
+        return $"{MetaData.Role}: {Content} [{MetaData.CreateTime}]";
+    }
 }
 
 public class DialogMetaData

src/Infrastructure/BotSharp.Abstraction/Conversations/Settings/ConversationSetting.cs

@@ -12,6 +12,7 @@ public class ConversationSetting
     public bool EnableContentLog { get; set; }
     public bool EnableStateLog { get; set; }
     public CleanConversationSetting CleanSetting { get; set; }
+    public RateLimitSetting RateLimit { get; set; }
 }
 
 public class CleanConversationSetting

src/Infrastructure/BotSharp.Abstraction/Conversations/Settings/RateLimitSetting.cs

@@ -0,0 +1,8 @@
+namespace BotSharp.Abstraction.Conversations.Settings;
+
+public class RateLimitSetting
+{
+    public int MaxConversationPerDay { get; set; } = 100;
+    public int MaxInputLengthPerRequest { get; set; } = 256;
+    public int MinTimeSecondsBetweenMessages { get; set; } = 2;
+}

src/Infrastructure/BotSharp.Abstraction/Routing/IRoutingService.cs

@@ -32,7 +32,7 @@ public interface IRoutingService
     void ResetRecursiveCounter();
     Task<bool> InvokeAgent(string agentId, List<RoleDialogModel> dialogs);
     Task<bool> InvokeFunction(string name, RoleDialogModel message);
-    Task<RoleDialogModel> InstructLoop(RoleDialogModel message);
+    Task<RoleDialogModel> InstructLoop(RoleDialogModel message, List<RoleDialogModel> dialogs);
 
     /// <summary>
     /// Talk to a specific Agent directly, bypassing the Router

src/Infrastructure/BotSharp.Core/Conversations/Services/ConversationService.SendMessage.cs

@@ -34,6 +34,9 @@ public partial class ConversationService
 
         _storage.Append(_conversationId, message);
 
+        var conv = _services.GetRequiredService<IConversationService>();
+        var dialogs = conv.GetDialogHistory();
+
         var statistics = _services.GetRequiredService<ITokenStatistics>();
         var hooks = _services.GetServices<IConversationHook>().ToList();
 
@@ -75,7 +78,7 @@ public partial class ConversationService
             var settings = _services.GetRequiredService<RoutingSettings>();
 
             response = agent.Type == AgentType.Routing ?
-                await routing.InstructLoop(message) :
+                await routing.InstructLoop(message, dialogs) :
                 await routing.InstructDirect(agent, message);
 
             routing.ResetRecursiveCounter();

src/Infrastructure/BotSharp.Core/Routing/Functions/FallbackToRouterFn.cs

@@ -1,7 +1,5 @@
 using BotSharp.Abstraction.Functions;
-using BotSharp.Abstraction.Repositories.Filters;
 using BotSharp.Abstraction.Routing.Models;
-using BotSharp.Abstraction.Routing;
 
 namespace BotSharp.Core.Routing.Functions;
 
@@ -29,12 +27,14 @@ public class FallbackToRouterFn : IFunctionCallback
             return false;
         }
 
-        var routing = _services.GetRequiredService<IRoutingContext>();
-        routing.Replace(targetAgent.Id);
+        var conv = _services.GetRequiredService<IConversationService>();
+        var dialogs = conv.GetDialogHistory();
 
-        var router = _services.GetRequiredService<IRoutingService>();
+        var routing = _services.GetRequiredService<IRoutingService>();
+        routing.Context.Replace(targetAgent.Id);
         message.CurrentAgentId = targetAgent.Id;
-        var response = await router.InstructLoop(message);
+
+        var response = await routing.InstructLoop(message, dialogs);
 
         message.Content = response.Content;
         message.StopCompletion = true;

src/Infrastructure/BotSharp.Core/Routing/RoutingService.cs

@@ -69,7 +69,7 @@ public partial class RoutingService : IRoutingService
         return response;
     }
 
-    public async Task<RoleDialogModel> InstructLoop(RoleDialogModel message)
+    public async Task<RoleDialogModel> InstructLoop(RoleDialogModel message, List<RoleDialogModel> dialogs)
     {
         var agentService = _services.GetRequiredService<IAgentService>();
         _router = await agentService.LoadAgent(message.CurrentAgentId);
@@ -77,9 +77,6 @@ public partial class RoutingService : IRoutingService
         RoleDialogModel response = default;
 
         var states = _services.GetRequiredService<IConversationStateService>();
-        var conv = _services.GetRequiredService<IConversationService>();
-        var dialogs = conv.GetDialogHistory();
-
         var executor = _services.GetRequiredService<IExecutor>();
 
         var planner = GetPlanner(_router);

src/Infrastructure/BotSharp.Logger/BotSharpLoggerExtensions.cs

@@ -13,6 +13,7 @@ public static class BotSharpLoggerExtensions
         services.AddScoped<IContentGeneratingHook, CommonContentGeneratingHook>();
         services.AddScoped<IContentGeneratingHook, TokenStatsConversationHook>();
         services.AddScoped<IContentGeneratingHook, VerboseLogHook>();
+        services.AddScoped<IConversationHook, RateLimitConversationHook>();
         return services;
     }
 }

src/Infrastructure/BotSharp.Logger/Hooks/RateLimitConversationHook.cs

@@ -0,0 +1,65 @@
+using BotSharp.Abstraction.Agents.Enums;
+using BotSharp.Abstraction.Repositories.Filters;
+using BotSharp.Abstraction.Users;
+
+namespace BotSharp.Logger.Hooks;
+
+/// <summary>
+/// To prevent users from overusing, if the character limit is exceeded or the sending frequency is too fast, 
+/// a prompt message will be returned.
+/// </summary>
+public class RateLimitConversationHook : ConversationHookBase
+{
+    private readonly IServiceProvider _services;
+    private readonly ILogger _logger;
+    public RateLimitConversationHook(IServiceProvider services, ILogger<RateLimitConversationHook> logger)
+    {
+        _services = services;
+        _logger = logger;
+    }
+
+    public override async Task OnMessageReceived(RoleDialogModel message)
+    {
+        var settings = _services.GetRequiredService<ConversationSetting>();
+        var rateLimit = settings.RateLimit;
+
+        // Check max input length
+        var charCount = message.Content.Length;
+        if (charCount > rateLimit.MaxInputLengthPerRequest)
+        {
+            message.Content = $"The number of characters in your message exceeds the system maximum of {rateLimit.MaxInputLengthPerRequest}";
+            message.StopCompletion = true;
+            return;
+        }
+
+        // Check message sending frequency
+        var userSents = _dialogs.Where(x => x.Role == AgentRole.User)
+            .TakeLast(2).ToList();
+
+        if (userSents.Count > 1)
+        {
+            var seconds = (DateTime.UtcNow - userSents.First().CreatedAt).TotalSeconds;
+            if (seconds < rateLimit.MinTimeSecondsBetweenMessages)
+            {
+                message.Content = "Your message sending frequency exceeds the frequency specified by the system. Please try again later.";
+                message.StopCompletion = true;
+                return;
+            }
+        }
+
+        // Check the number of conversations
+        var user = _services.GetRequiredService<IUserIdentity>();
+        var convService = _services.GetRequiredService<IConversationService>();
+        var results = await convService.GetConversations(new ConversationFilter
+        {
+            UserId = user.Id
+        });
+
+        if (results.Count > rateLimit.MaxConversationPerDay)
+        {
+            message.Content = $"The number of conversations you have exceeds the system maximum of {rateLimit.MaxConversationPerDay}";
+            message.StopCompletion = true;
+            return;
+        }
+    }
+}

src/WebStarter/appsettings.json

@@ -125,6 +125,11 @@
       "BatchSize": 50,
       "MessageLimit": 2,
       "BufferHours": 12
+    },
+    "RateLimit": {
+      "MaxConversationPerDay": 100,
+      "MaxInputLengthPerRequest": 256,
+      "MinTimeSecondsBetweenMessages": 2
     }
   },