Simplified SQLite vector store creation

src/libs/Databases/LangChain.Databases.Sqlite/SQLIteVectorStoreOptions.cs

@@ -0,0 +1,9 @@
+namespace LangChain.Databases;
+
+public class SQLIteVectorStoreOptions
+{
+    public string Filename { get; set; } = "vectors.db";
+    public string TableName { get; set; } = "vectors";
+    public int ChunkSize { get; set; } = 200;
+    public int ChunkOverlap { get; set; } = 50;
+}

src/libs/Databases/LangChain.Databases.Sqlite/SQLiteVectorStore.cs

@@ -41,6 +41,36 @@ public static async Task<VectorStoreIndexWrapper> CreateIndexFromDocuments(
         return index;
     }
 
+    public static SQLIteVectorStoreOptions DefaultOptions = new SQLIteVectorStoreOptions();
+
+    /// <summary>
+    ///  If database does not exists, it loads documents from the documentsSource, creates an index from these documents and returns the created index.
+    ///  If database exists, it loads the index from the database.
+    ///  documentsSource is used only if the database does not exist. If the database exists, documentsSource is ignored.
+    /// </summary>
+    /// <param name="embeddings">An object implementing the <see cref="IEmbeddings"/> interface. This object is used to generate embeddings for the documents.</param>
+    /// <param name="documentsSource">An optional object implementing the <see cref="ISource"/> interface. This object is used to load documents if the vector store database file does not exist.</param>
+    /// <param name="options">An optional <see cref="SQLIteVectorStoreOptions"/> object. This object provides configuration options for the SQLite vector store</param>
+    public static async Task<VectorStoreIndexWrapper> GetIndex(
+        IEmbeddings embeddings, ISource? documentsSource=null, SQLIteVectorStoreOptions? options=null)
+    {
+        options ??= DefaultOptions;
+
+
+        TextSplitter textSplitter = new RecursiveCharacterTextSplitter(chunkSize: options.ChunkSize, chunkOverlap: options.ChunkOverlap);
+
+        if (!System.IO.File.Exists("vectors.db"))
+        {
+            var documents = await documentsSource.LoadAsync();
+            return await SQLiteVectorStore.CreateIndexFromDocuments(embeddings, documents, options.Filename, options.TableName, textSplitter: textSplitter);
+        }
+
+
+        var vectorStore = new SQLiteVectorStore(options.Filename, options.TableName, embeddings);
+        var index = new VectorStoreIndexWrapper(vectorStore);
+        return index;
+    }
+
     /// <summary>
     /// 
     /// </summary>

src/libs/LangChain.Core/Providers/Extensions/WithDebugExtensions.cs

@@ -0,0 +1,11 @@
+namespace LangChain.Providers;
+
+public static class WithDebugExtensions
+{
+    public static T UseConsoleForDebug<T>(this T model) where T : IWithDebug
+    {
+        model.PromptSent += Console.Write;
+        model.TokenGenerated += Console.Write;
+        return model;
+    }
+}

src/libs/LangChain.Core/Providers/IWithDebug.cs

@@ -0,0 +1,14 @@
+namespace LangChain.Providers;
+
+public interface IWithDebug
+{
+    /// <summary>
+    /// Occurs when token generated.
+    /// </summary>
+    public event Action<string> TokenGenerated;
+
+    /// <summary>
+    /// Occurs before prompt is sent to the model.
+    /// </summary>
+    public event Action<string> PromptSent;
+}

src/libs/Providers/LangChain.Providers.LLamaSharp/LLamaSharpModelInstruction.cs

@@ -8,7 +8,7 @@ namespace LangChain.Providers.LLamaSharp;
 /// 
 /// </summary>
 [CLSCompliant(false)]
-public class LLamaSharpModelInstruction : LLamaSharpModelBase
+public class LLamaSharpModelInstruction : LLamaSharpModelBase, IWithDebug
 {
 
 

src/libs/Providers/LangChain.Providers.Ollama/OllamaLanguageModelInstruction.cs

@@ -5,7 +5,7 @@ namespace LangChain.Providers;
 /// <summary>
 /// 
 /// </summary>
-public class OllamaLanguageModelInstruction : IChatModel
+public class OllamaLanguageModelInstruction : IChatModel, IWithDebug
 {
     private readonly string _modelName;
     private readonly OllamaApiClient _api;