Hook for chain execution tracing

LangChain.sln

@@ -164,15 +164,13 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LangChain.Providers.Google.
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LangChain.Providers.Azure", "src\libs\Providers\LangChain.Providers.Azure\LangChain.Providers.Azure.csproj", "{18F5AAB1-1750-41BD-B623-6339CA5754D9}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "LangChain.Providers.Ollama.IntegrationTests", "src\tests\LangChain.Providers.Ollama.IntegrationTests\LangChain.Providers.Ollama.IntegrationTests.csproj", "{72B1E2CC-1A34-470E-A579-034CB0972BB7}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LangChain.Providers.Ollama.IntegrationTests", "src\tests\LangChain.Providers.Ollama.IntegrationTests\LangChain.Providers.Ollama.IntegrationTests.csproj", "{72B1E2CC-1A34-470E-A579-034CB0972BB7}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LangChain.Providers.Ollama", "src\libs\Providers\LangChain.Providers.Ollama\LangChain.Providers.Ollama.csproj", "{4913844F-74EC-4E74-AE8A-EA825569E6BA}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "LangChain.Providers.Automatic1111", "src\libs\Providers\LangChain.Providers.Automatic1111\LangChain.Providers.Automatic1111.csproj", "{BF4C7B87-0997-4208-84EF-D368DF7B9861}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LangChain.Providers.Automatic1111", "src\libs\Providers\LangChain.Providers.Automatic1111\LangChain.Providers.Automatic1111.csproj", "{BF4C7B87-0997-4208-84EF-D368DF7B9861}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "LangChain.Providers.Automatic1111.IntegrationTests", "src\tests\LangChain.Providers.Automatic1111.IntegrationTests\LangChain.Providers.Automatic1111.IntegrationTests.csproj", "{A6CF79BC-8365-46E8-9230-1A4AD615D40B}"
-EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "LangChain.Providers.Azure", "src\libs\Providers\LangChain.Providers.Azure\LangChain.Providers.Azure.csproj", "{738984A2-7D3F-42E7-9B4D-3528E2539197}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LangChain.Providers.Automatic1111.IntegrationTests", "src\tests\LangChain.Providers.Automatic1111.IntegrationTests\LangChain.Providers.Automatic1111.IntegrationTests.csproj", "{A6CF79BC-8365-46E8-9230-1A4AD615D40B}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -404,10 +402,6 @@ Global
 		{A6CF79BC-8365-46E8-9230-1A4AD615D40B}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{A6CF79BC-8365-46E8-9230-1A4AD615D40B}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{A6CF79BC-8365-46E8-9230-1A4AD615D40B}.Release|Any CPU.Build.0 = Release|Any CPU
-		{738984A2-7D3F-42E7-9B4D-3528E2539197}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{738984A2-7D3F-42E7-9B4D-3528E2539197}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{738984A2-7D3F-42E7-9B4D-3528E2539197}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{738984A2-7D3F-42E7-9B4D-3528E2539197}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -475,7 +469,6 @@ Global
 		{4913844F-74EC-4E74-AE8A-EA825569E6BA} = {E55391DE-F8F3-4CC2-A0E3-2406C76E9C68}
 		{BF4C7B87-0997-4208-84EF-D368DF7B9861} = {E55391DE-F8F3-4CC2-A0E3-2406C76E9C68}
 		{A6CF79BC-8365-46E8-9230-1A4AD615D40B} = {FDEE2E22-C239-4921-83B2-9797F765FD6A}
-		{738984A2-7D3F-42E7-9B4D-3528E2539197} = {E55391DE-F8F3-4CC2-A0E3-2406C76E9C68}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {5C00D0F1-6138-4ED9-846B-97E43D6DFF1C}

src/libs/LangChain.Core/Chains/StackableChains/BaseStackableChain.cs

@@ -2,6 +2,7 @@
 using LangChain.Abstractions.Schema;
 using LangChain.Callback;
 using LangChain.Chains.HelperChains.Exceptions;
+using LangChain.Chains.StackableChains.Context;
 using LangChain.Schema;
 
 namespace LangChain.Chains.HelperChains;
@@ -86,10 +87,13 @@ string FormatInputValues(IChainValues values)
     public Task<IChainValues> CallAsync(IChainValues values, ICallbacks? callbacks = null,
         IReadOnlyList<string>? tags = null, IReadOnlyDictionary<string, object>? metadata = null)
     {
+
+
         if (values == null)
         {
             throw new ArgumentNullException(nameof(values));
         }
+
         try
         {
             return InternalCall(values);
@@ -108,8 +112,9 @@ public Task<IChainValues> CallAsync(IChainValues values, ICallbacks? callbacks =
 
             throw new StackableChainException(message, ex);
         }
+
     }
-    
+
     /// <summary>
     /// 
     /// </summary>
@@ -143,9 +148,11 @@ public static StackChain BitwiseOr(BaseStackableChain left, BaseStackableChain r
     /// 
     /// </summary>
     /// <returns></returns>
-    public async Task<IChainValues> Run()
+    public async Task<IChainValues> Run(StackableChainHook? hook=null)
     {
-        var res = await CallAsync(new ChainValues()).ConfigureAwait(false);
+        var values = new StackableChainValues() {Hook = hook};
+        hook?.ChainStart(values);
+        var res = await CallAsync(values).ConfigureAwait(false);
         return res;
     }
 
@@ -154,9 +161,9 @@ public async Task<IChainValues> Run()
     /// </summary>
     /// <param name="resultKey"></param>
     /// <returns></returns>
-    public async Task<string?> Run(string resultKey)
+    public async Task<string?> Run(string resultKey, StackableChainHook? hook = null)
     {
-        var res = await CallAsync(new ChainValues()).ConfigureAwait(false);
+        var res = await CallAsync(new StackableChainValues() { Hook = hook }).ConfigureAwait(false);
         return res.Value[resultKey].ToString();
     }
 
@@ -166,12 +173,17 @@ public async Task<IChainValues> Run()
     /// <param name="resultKey"></param>
     /// <typeparam name="T"></typeparam>
     /// <returns></returns>
-    public async Task<T> Run<T>(string resultKey)
+    public async Task<T> Run<T>(string resultKey, StackableChainHook? hook = null)
     {
-        var res = await CallAsync(new ChainValues()).ConfigureAwait(false);
+        var res = await CallAsync(new StackableChainValues() { Hook = hook }).ConfigureAwait(false);
         return (T)res.Value[resultKey];
     }
 
+    public Task<string?> Run(string resultKey)
+    {
+        return Run(resultKey, null);
+    }
+
     /// <summary>
     /// 
     /// </summary>

src/libs/LangChain.Core/Chains/StackableChains/Hooks/ConsoleTraceHook.cs

@@ -0,0 +1,102 @@
+
+using LangChain.Chains.HelperChains;
+
+namespace LangChain.Chains.StackableChains.Context;
+
+public class ConsoleTraceHook: StackableChainHook
+{
+    public bool UseColors { get; set; }=true;
+    public int ValuesLength { get; set; } = 40;
+    public override void ChainStart(StackableChainValues values)
+    {
+        Console.WriteLine();
+    }
+    public override void LinkEnter(BaseStackableChain chain, StackableChainValues values)
+    {
+
+        Console.Write("|");
+        Console.Write(chain.GetType().Name);
+        Console.WriteLine();
+        if (chain.InputKeys.Count > 0)
+        {
+            Console.Write("|");
+            Console.Write("  ");
+            Console.Write("\u2514");
+            Console.Write("Input:");
+            Console.WriteLine();
+            foreach (string inputKey in chain.InputKeys)
+            {
+                Console.Write("|");
+                Console.Write("   ");
+                Console.Write("\u2514");
+                var value = values.Value[inputKey];
+                var oldColor = Console.ForegroundColor;
+                Console.ForegroundColor = GetColorForKey(inputKey);
+                Console.Write($" {inputKey}={ShortenString(value.ToString() ?? "", ValuesLength)}");
+                Console.ForegroundColor = oldColor;
+                Console.WriteLine();
+            }
+        }
+
+
+    }
+
+    Dictionary<string, ConsoleColor> _colorMap = new Dictionary<string, ConsoleColor>();
+
+    ConsoleColor GetColorForKey(string key)
+    {
+        if(!UseColors)
+            return Console.ForegroundColor;
+        // if key is not in map, get unique color(except black and white)
+        // if there no unique colors left, return white
+        if (!_colorMap.ContainsKey(key))
+        {
+            var color = ConsoleColor.White;
+            var colors = Enum.GetValues(typeof(ConsoleColor));
+            foreach (ConsoleColor c in colors)
+            {
+                if (c == ConsoleColor.Black || c == ConsoleColor.White)
+                    continue;
+                if (!_colorMap.ContainsValue(c))
+                {
+                    color = c;
+                    break;
+                }
+            }
+            _colorMap.Add(key, color);
+        }
+        return _colorMap[key];
+    }
+
+    string ShortenString(string str, int length)
+    {
+        if (str.Length <= length)
+            return str;
+        return str.Substring(0, length - 3) + "...";
+    }
+
+    public override void LinkExit(BaseStackableChain chain, StackableChainValues values)
+    {
+        if (chain.OutputKeys.Count > 0)
+        {
+            Console.Write("|");
+            Console.Write("  ");
+            Console.Write("\u2514");
+            Console.Write("Output:");
+            Console.WriteLine();
+            foreach (string outputKey in chain.OutputKeys)
+            {
+                Console.Write("|");
+                Console.Write("   ");
+                Console.Write("\u2514");
+                var value = values.Value[outputKey];
+                var oldColor = Console.ForegroundColor;
+                Console.ForegroundColor = GetColorForKey(outputKey);
+                Console.Write($" {outputKey}={ShortenString(value.ToString() ?? "", ValuesLength)}");
+                Console.ForegroundColor = oldColor;
+                Console.WriteLine();
+            }
+        }
+
+    }
+}

src/libs/LangChain.Core/Chains/StackableChains/Hooks/StackableChainHook.cs

@@ -0,0 +1,21 @@
+using LangChain.Chains.HelperChains;
+
+namespace LangChain.Chains.StackableChains.Context;
+
+public class StackableChainHook
+{
+    public virtual void ChainStart(StackableChainValues values)
+    {
+
+    }
+
+    public virtual void LinkEnter(BaseStackableChain chain, StackableChainValues values)
+    {
+
+    }
+
+    public virtual void LinkExit(BaseStackableChain chain, StackableChainValues values)
+    {
+
+    }
+}

src/libs/LangChain.Core/Chains/StackableChains/Hooks/StackableChainValues.cs

@@ -0,0 +1,8 @@
+using LangChain.Schema;
+
+namespace LangChain.Chains.StackableChains.Context;
+
+public class StackableChainValues : ChainValues
+{
+    public StackableChainHook? Hook { get; set; }
+}

src/libs/LangChain.Core/Chains/StackableChains/StackChain.cs

@@ -1,4 +1,5 @@
 using LangChain.Abstractions.Schema;
+using LangChain.Chains.StackableChains.Context;
 using LangChain.Schema;
 
 namespace LangChain.Chains.HelperChains;
@@ -60,15 +61,25 @@
 
         if (IsolatedInputKeys.Count > 0)
         {
-            var res = new ChainValues();
+            var res = new StackableChainValues(){Hook = (values as StackableChainValues)?.Hook};
             foreach (var key in IsolatedInputKeys)
             {
                 res.Value[key] = values.Value[key];
             }
             values = res;
         }
+        if(a is not StackChain)
+            (values as StackableChainValues)?.Hook?.LinkEnter(a, (values as StackableChainValues));
         await a.CallAsync(values).ConfigureAwait(false);
+        if (a is not StackChain)
+            (values as StackableChainValues)?.Hook?.LinkExit(a, (values as StackableChainValues));
+
+        if (b is not StackChain)
+            (values as StackableChainValues)?.Hook?.LinkEnter(b, (values as StackableChainValues));
         await b.CallAsync(values).ConfigureAwait(false);
+        if (b is not StackChain)
+            (values as StackableChainValues)?.Hook?.LinkExit(b, (values as StackableChainValues));
+
         if (IsolatedOutputKeys.Count > 0)
         {
             foreach (var key in IsolatedOutputKeys)