LLama.Examples: improve model path prompt (#526)

* LLama.Examples: RepoUtils.cs → ConsoleLogger.cs

* LLama.Examples: Examples/Runner.cs → ExampleRunner.cs

* LLama.Examples: delete unused console logger

* LLama.Examples: improve splash screen appearance

the llama_empty_call() no longer shows configuration information on startup, but it will display it automatically the first time a model is engaged

* LLama.Examples: Runner → ExampleRunner

* LLama.Examples: improve model path prompt

The last used model is stored in a config file and is re-used when a blank path is provided

* LLama.Examples: NativeApi.llama_empty_call() at startup

* LLama.Examples: reduce console noise when saving model path

Author: swharden

LLama.Examples/Examples/Runner.cs renamed to LLama.Examples/ExampleRunner.cs

@@ -1,8 +1,7 @@
 using Spectre.Console;
+using LLama.Examples.Examples;
 
-namespace LLama.Examples.Examples;
-
-public class Runner
+public class ExampleRunner
 {
     private static readonly Dictionary<string, Func<Task>> Examples = new()
     {
@@ -26,7 +25,7 @@ public class Runner
         { "Batched Executor (Fork)", BatchedExecutorFork.Run },
         { "Batched Executor (Rewind)", BatchedExecutorRewind.Run },
         { "SK Kernel Memory.", KernelMemory.Run },
-        { "Exit", async () => Environment.Exit(0) }
+        { "Exit", () => { Environment.Exit(0); return Task.CompletedTask; } }
     };
 
     public static async Task Run()

LLama.Examples/Examples/BatchedExecutorFork.cs

@@ -15,8 +15,7 @@ public class BatchedExecutorFork
 
     public static async Task Run()
     {
-        Console.Write("Please input your model path: ");
-        var modelPath = Console.ReadLine();
+        string modelPath = UserSettings.GetModelPath();
 
         var parameters = new ModelParams(modelPath);
         using var model = LLamaWeights.LoadFromFile(parameters);

LLama.Examples/Examples/BatchedExecutorRewind.cs

@@ -16,8 +16,7 @@ public class BatchedExecutorRewind
 
     public static async Task Run()
     {
-        Console.Write("Please input your model path: ");
-        var modelPath = Console.ReadLine();
+        string modelPath = UserSettings.GetModelPath();
 
         var parameters = new ModelParams(modelPath);
         using var model = LLamaWeights.LoadFromFile(parameters);

LLama.Examples/Examples/ChatChineseGB2312.cs

@@ -22,8 +22,7 @@ public static async Task Run()
             " to use https://huggingface.co/hfl/chinese-alpaca-2-7b-gguf/blob/main/ggml-model-q5_0.gguf, which has been verified by LLamaSharp developers.");
         Console.ForegroundColor = ConsoleColor.White;
 
-        Console.Write("Please input your model path: ");
-        var modelPath = Console.ReadLine();
+        string modelPath = UserSettings.GetModelPath();
 
         var parameters = new ModelParams(modelPath)
         {

LLama.Examples/Examples/ChatSessionStripRoleName.cs

@@ -6,8 +6,7 @@ public class ChatSessionStripRoleName
 {
     public static async Task Run()
     {
-        Console.Write("Please input your model path: ");
-        var modelPath = Console.ReadLine();
+        string modelPath = UserSettings.GetModelPath();
 
         var parameters = new ModelParams(modelPath)
         {

LLama.Examples/Examples/ChatSessionWithHistory.cs

@@ -6,8 +6,7 @@ public class ChatSessionWithHistory
 {
     public static async Task Run()
     {
-        Console.Write("Please input your model path: ");
-        var modelPath = Console.ReadLine();
+        string modelPath = UserSettings.GetModelPath();
 
         var parameters = new ModelParams(modelPath)
         {

LLama.Examples/Examples/ChatSessionWithRoleName.cs

@@ -6,8 +6,7 @@ public class ChatSessionWithRoleName
 {
     public static async Task Run()
     {
-        Console.Write("Please input your model path: ");
-        var modelPath = Console.ReadLine();
+        string modelPath = UserSettings.GetModelPath();
 
         var parameters = new ModelParams(modelPath)
         {

LLama.Examples/Examples/CodingAssistant.cs

@@ -2,27 +2,27 @@
 {
     using LLama.Common;
     using System;
-    using System.Reflection;
 
     internal class CodingAssistant
     {
-        const string DefaultModelUri = "https://huggingface.co/TheBloke/CodeLlama-7B-Instruct-GGUF/resolve/main/codellama-7b-instruct.Q4_K_S.gguf";
-
         // Source paper with example prompts:
         // https://doi.org/10.48550/arXiv.2308.12950
         const string InstructionPrefix = "[INST]";
         const string InstructionSuffix = "[/INST]";
-        const string SystemInstruction = "You're an intelligent, concise coding assistant. Wrap code in ``` for readability. Don't repeat yourself. Use best practice and good coding standards.";
-        private static string ModelsDirectory = Path.Combine(Directory.GetParent(Assembly.GetExecutingAssembly().Location)!.FullName, "Models");
+        const string SystemInstruction = "You're an intelligent, concise coding assistant. " +
+            "Wrap code in ``` for readability. Don't repeat yourself. " +
+            "Use best practice and good coding standards.";
 
         public static async Task Run()
         {
-            Console.Write("Please input your model path (if left empty, a default model will be downloaded for you): ");
-            var modelPath = Console.ReadLine();
-
-            if(string.IsNullOrWhiteSpace(modelPath) )
+            string modelPath = UserSettings.GetModelPath();
+            if (!modelPath.Contains("codellama", StringComparison.InvariantCultureIgnoreCase))
             {
-                modelPath = await GetDefaultModel();
+                Console.ForegroundColor = ConsoleColor.Yellow;
+                Console.WriteLine("WARNING: the model you selected is not a Code LLama model!");
+                Console.WriteLine("For this example we specifically recommend 'codellama-7b-instruct.Q4_K_S.gguf'");
+                Console.WriteLine("Press ENTER to continue...");
+                Console.ReadLine();
             }
 
             var parameters = new ModelParams(modelPath)
@@ -35,12 +35,14 @@ public static async Task Run()
 
             Console.ForegroundColor = ConsoleColor.Yellow;
             Console.WriteLine("The executor has been enabled. In this example, the LLM will follow your instructions." +
-                "\nIt's a 7B Code Llama, so it's trained for programming tasks like \"Write a C# function reading a file name from a given URI\" or \"Write some programming interview questions\"." +
+                "\nIt's a 7B Code Llama, so it's trained for programming tasks like \"Write a C# function reading " +
+                "a file name from a given URI\" or \"Write some programming interview questions\"." +
                 "\nWrite 'exit' to exit");
             Console.ForegroundColor = ConsoleColor.White;
 
-            var inferenceParams = new InferenceParams() { 
-                Temperature = 0.8f, 
+            var inferenceParams = new InferenceParams()
+            {
+                Temperature = 0.8f,
                 MaxTokens = -1,
             };
 
@@ -51,7 +53,7 @@ public static async Task Run()
             {
 
                 Console.ForegroundColor = ConsoleColor.Green;
-                await foreach (var text in executor.InferAsync(instruction + System.Environment.NewLine, inferenceParams))
+                await foreach (var text in executor.InferAsync(instruction + Environment.NewLine, inferenceParams))
                 {
                     Console.Write(text);
                 }
@@ -61,34 +63,5 @@ public static async Task Run()
                 instruction = Console.ReadLine() ?? "Ask me for instructions.";
             }
         }
-
-        private static async Task<string> GetDefaultModel()
-        {
-            var uri = new Uri(DefaultModelUri);
-            var modelName = uri.Segments[^1];
-            await Console.Out.WriteLineAsync($"The following model will be used: {modelName}");
-            var modelPath = Path.Combine(ModelsDirectory, modelName);
-            if(!Directory.Exists(ModelsDirectory))
-            {
-                Directory.CreateDirectory(ModelsDirectory);
-            }
-
-            if (File.Exists(modelPath))
-            {
-                await Console.Out.WriteLineAsync($"Existing model found, using {modelPath}");
-            }
-            else
-            {
-                await Console.Out.WriteLineAsync($"Model not found locally, downloading {DefaultModelUri}...");
-                using var http = new HttpClient();
-                await using var downloadStream = await http.GetStreamAsync(uri);
-                await using var fileStream = new FileStream(modelPath, FileMode.Create, FileAccess.Write);
-                await downloadStream.CopyToAsync(fileStream);
-                await Console.Out.WriteLineAsync($"Model downloaded and saved to {modelPath}");
-            }
-
-
-            return modelPath;
-        }
     }
 }

LLama.Examples/Examples/GetEmbeddings.cs

@@ -6,9 +6,7 @@ public class GetEmbeddings
     {
         public static void Run()
         {
-            Console.ForegroundColor = ConsoleColor.White;
-            Console.Write("Please input your model path: ");
-            var modelPath = Console.ReadLine();
+            string modelPath = UserSettings.GetModelPath();
 
             Console.ForegroundColor = ConsoleColor.DarkGray;
             var @params = new ModelParams(modelPath) { EmbeddingMode = true };

LLama.Examples/Examples/GrammarJsonResponse.cs

@@ -7,11 +7,10 @@ public class GrammarJsonResponse
     {
         public static async Task Run()
         {
-            var gbnf = (await File.ReadAllTextAsync("Assets/json.gbnf")).Trim();
-            var grammar = Grammar.Parse(gbnf, "root");
+            string modelPath = UserSettings.GetModelPath();
 
-            Console.Write("Please input your model path: ");
-            var modelPath = Console.ReadLine();
+            var gbnf = File.ReadAllText("Assets/json.gbnf").Trim();
+            var grammar = Grammar.Parse(gbnf, "root");
 
             var parameters = new ModelParams(modelPath)
             {
@@ -27,10 +26,10 @@ public static async Task Run()
             Console.ForegroundColor = ConsoleColor.White;
 
             using var grammarInstance = grammar.CreateInstance();
-            var inferenceParams = new InferenceParams() 
-            { 
-                Temperature = 0.6f, 
-                AntiPrompts = new List<string> { "Question:", "#", "Question: ", ".\n" }, 
+            var inferenceParams = new InferenceParams()
+            {
+                Temperature = 0.6f,
+                AntiPrompts = new List<string> { "Question:", "#", "Question: ", ".\n" },
                 MaxTokens = 50,
                 Grammar = grammarInstance
             };