.Net: Ollama - Adding Missing Samples (#8309)

### Motivation and Context

Adding missing samples using the new Ollama Connector.
- Embedding generation
- Text Generation
- Chat Completion
- AIModelRouting Demo with Ollama Connector

dotnet/samples/Concepts/ChatCompletion/Ollama_ChatCompletion.cs

@@ -0,0 +1,114 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Text;
+using Microsoft.SemanticKernel;
+using Microsoft.SemanticKernel.ChatCompletion;
+using Microsoft.SemanticKernel.Connectors.Ollama;
+
+namespace ChatCompletion;
+
+// The following example shows how to use Semantic Kernel with Ollama Chat Completion API
+public class Ollama_ChatCompletion(ITestOutputHelper output) : BaseTest(output)
+{
+    [Fact]
+    public async Task ServicePromptAsync()
+    {
+        Assert.NotNull(TestConfiguration.Ollama.ModelId);
+
+        Console.WriteLine("======== Ollama - Chat Completion ========");
+
+        var chatService = new OllamaChatCompletionService(
+            endpoint: new Uri(TestConfiguration.Ollama.Endpoint),
+            modelId: TestConfiguration.Ollama.ModelId);
+
+        Console.WriteLine("Chat content:");
+        Console.WriteLine("------------------------");
+
+        var chatHistory = new ChatHistory("You are a librarian, expert about books");
+
+        // First user message
+        chatHistory.AddUserMessage("Hi, I'm looking for book suggestions");
+        await MessageOutputAsync(chatHistory);
+
+        // First assistant message
+        var reply = await chatService.GetChatMessageContentAsync(chatHistory);
+        chatHistory.Add(reply);
+        await MessageOutputAsync(chatHistory);
+
+        // Second user message
+        chatHistory.AddUserMessage("I love history and philosophy, I'd like to learn something new about Greece, any suggestion");
+        await MessageOutputAsync(chatHistory);
+
+        // Second assistant message
+        reply = await chatService.GetChatMessageContentAsync(chatHistory);
+        chatHistory.Add(reply);
+        await MessageOutputAsync(chatHistory);
+
+        /* Output:
+
+        Chat content:
+        ------------------------
+        System: You are a librarian, expert about books
+        ------------------------
+        User: Hi, I'm looking for book suggestions
+        ------------------------
+        Assistant: Sure, I'd be happy to help! What kind of books are you interested in? Fiction or non-fiction? Any particular genre?
+        ------------------------
+        User: I love history and philosophy, I'd like to learn something new about Greece, any suggestion?
+        ------------------------
+        Assistant: Great! For history and philosophy books about Greece, here are a few suggestions:
+
+        1. "The Greeks" by H.D.F. Kitto - This is a classic book that provides an overview of ancient Greek history and culture, including their philosophy, literature, and art.
+
+        2. "The Republic" by Plato - This is one of the most famous works of philosophy in the Western world, and it explores the nature of justice and the ideal society.
+
+        3. "The Peloponnesian War" by Thucydides - This is a detailed account of the war between Athens and Sparta in the 5th century BCE, and it provides insight into the political and military strategies of the time.
+
+        4. "The Iliad" by Homer - This epic poem tells the story of the Trojan War and is considered one of the greatest works of literature in the Western canon.
+
+        5. "The Histories" by Herodotus - This is a comprehensive account of the Persian Wars and provides a wealth of information about ancient Greek culture and society.
+
+        I hope these suggestions are helpful!
+        ------------------------
+        */
+    }
+
+    [Fact]
+    public async Task ChatPromptAsync()
+    {
+        Assert.NotNull(TestConfiguration.Ollama.ModelId);
+
+        StringBuilder chatPrompt = new("""
+                                       <message role="system">You are a librarian, expert about books</message>
+                                       <message role="user">Hi, I'm looking for book suggestions</message>
+                                       """);
+
+        var kernel = Kernel.CreateBuilder()
+            .AddOllamaChatCompletion(
+                endpoint: new Uri(TestConfiguration.Ollama.Endpoint ?? "http://localhost:11434"),
+                modelId: TestConfiguration.Ollama.ModelId)
+            .Build();
+
+        var reply = await kernel.InvokePromptAsync(chatPrompt.ToString());
+
+        chatPrompt.AppendLine($"<message role=\"assistant\"><![CDATA[{reply}]]></message>");
+        chatPrompt.AppendLine("<message role=\"user\">I love history and philosophy, I'd like to learn something new about Greece, any suggestion</message>");
+
+        reply = await kernel.InvokePromptAsync(chatPrompt.ToString());
+
+        Console.WriteLine(reply);
+    }
+
+    /// <summary>
+    /// Outputs the last message of the chat history
+    /// </summary>
+    private Task MessageOutputAsync(ChatHistory chatHistory)
+    {
+        var message = chatHistory.Last();
+
+        Console.WriteLine($"{message.Role}: {message.Content}");
+        Console.WriteLine("------------------------");
+
+        return Task.CompletedTask;
+    }
+}

dotnet/samples/Concepts/ChatCompletion/Ollama_ChatCompletionStreaming.cs

@@ -0,0 +1,172 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Text;
+using Microsoft.SemanticKernel;
+using Microsoft.SemanticKernel.ChatCompletion;
+using Microsoft.SemanticKernel.Connectors.Ollama;
+
+namespace ChatCompletion;
+
+/// <summary>
+/// These examples demonstrate the ways different content types are streamed by Ollama via the chat completion service.
+/// </summary>
+public class Ollama_ChatCompletionStreaming(ITestOutputHelper output) : BaseTest(output)
+{
+    /// <summary>
+    /// This example demonstrates chat completion streaming using Ollama.
+    /// </summary>
+    [Fact]
+    public Task StreamChatAsync()
+    {
+        Assert.NotNull(TestConfiguration.Ollama.ModelId);
+
+        Console.WriteLine("======== Ollama - Chat Completion Streaming ========");
+
+        var chatService = new OllamaChatCompletionService(
+            endpoint: new Uri(TestConfiguration.Ollama.Endpoint),
+            modelId: TestConfiguration.Ollama.ModelId);
+
+        return this.StartStreamingChatAsync(chatService);
+    }
+
+    [Fact]
+    public async Task StreamChatPromptAsync()
+    {
+        Assert.NotNull(TestConfiguration.Ollama.ModelId);
+
+        StringBuilder chatPrompt = new("""
+                                       <message role="system">You are a librarian, expert about books</message>
+                                       <message role="user">Hi, I'm looking for book suggestions</message>
+                                       """);
+
+        var kernel = Kernel.CreateBuilder()
+            .AddOllamaChatCompletion(
+                endpoint: new Uri(TestConfiguration.Ollama.Endpoint),
+                modelId: TestConfiguration.Ollama.ModelId)
+            .Build();
+
+        var reply = await StreamMessageOutputFromKernelAsync(kernel, chatPrompt.ToString());
+
+        chatPrompt.AppendLine($"<message role=\"assistant\"><![CDATA[{reply}]]></message>");
+        chatPrompt.AppendLine("<message role=\"user\">I love history and philosophy, I'd like to learn something new about Greece, any suggestion</message>");
+
+        reply = await StreamMessageOutputFromKernelAsync(kernel, chatPrompt.ToString());
+
+        Console.WriteLine(reply);
+    }
+
+    /// <summary>
+    /// This example demonstrates how the chat completion service streams text content.
+    /// It shows how to access the response update via StreamingChatMessageContent.Content property
+    /// and alternatively via the StreamingChatMessageContent.Items property.
+    /// </summary>
+    [Fact]
+    public async Task StreamTextFromChatAsync()
+    {
+        Assert.NotNull(TestConfiguration.Ollama.ModelId);
+
+        Console.WriteLine("======== Stream Text from Chat Content ========");
+
+        // Create chat completion service
+        var chatService = new OllamaChatCompletionService(
+            endpoint: new Uri(TestConfiguration.Ollama.Endpoint),
+            modelId: TestConfiguration.Ollama.ModelId);
+
+        // Create chat history with initial system and user messages
+        ChatHistory chatHistory = new("You are a librarian, an expert on books.");
+        chatHistory.AddUserMessage("Hi, I'm looking for book suggestions.");
+        chatHistory.AddUserMessage("I love history and philosophy. I'd like to learn something new about Greece, any suggestion?");
+
+        // Start streaming chat based on the chat history
+        await foreach (StreamingChatMessageContent chatUpdate in chatService.GetStreamingChatMessageContentsAsync(chatHistory))
+        {
+            // Access the response update via StreamingChatMessageContent.Content property
+            Console.Write(chatUpdate.Content);
+
+            // Alternatively, the response update can be accessed via the StreamingChatMessageContent.Items property
+            Console.Write(chatUpdate.Items.OfType<StreamingTextContent>().FirstOrDefault());
+        }
+    }
+
+    private async Task StartStreamingChatAsync(IChatCompletionService chatCompletionService)
+    {
+        Console.WriteLine("Chat content:");
+        Console.WriteLine("------------------------");
+
+        var chatHistory = new ChatHistory("You are a librarian, expert about books");
+        OutputLastMessage(chatHistory);
+
+        // First user message
+        chatHistory.AddUserMessage("Hi, I'm looking for book suggestions");
+        OutputLastMessage(chatHistory);
+
+        // First assistant message
+        await StreamMessageOutputAsync(chatCompletionService, chatHistory, AuthorRole.Assistant);
+
+        // Second user message
+        chatHistory.AddUserMessage("I love history and philosophy, I'd like to learn something new about Greece, any suggestion?");
+        OutputLastMessage(chatHistory);
+
+        // Second assistant message
+        await StreamMessageOutputAsync(chatCompletionService, chatHistory, AuthorRole.Assistant);
+    }
+
+    private async Task StreamMessageOutputAsync(IChatCompletionService chatCompletionService, ChatHistory chatHistory, AuthorRole authorRole)
+    {
+        bool roleWritten = false;
+        string fullMessage = string.Empty;
+
+        await foreach (var chatUpdate in chatCompletionService.GetStreamingChatMessageContentsAsync(chatHistory))
+        {
+            if (!roleWritten && chatUpdate.Role.HasValue)
+            {
+                Console.Write($"{chatUpdate.Role.Value}: {chatUpdate.Content}");
+                roleWritten = true;
+            }
+
+            if (chatUpdate.Content is { Length: > 0 })
+            {
+                fullMessage += chatUpdate.Content;
+                Console.Write(chatUpdate.Content);
+            }
+        }
+
+        Console.WriteLine("\n------------------------");
+        chatHistory.AddMessage(authorRole, fullMessage);
+    }
+
+    private async Task<string> StreamMessageOutputFromKernelAsync(Kernel kernel, string prompt)
+    {
+        bool roleWritten = false;
+        string fullMessage = string.Empty;
+
+        await foreach (var chatUpdate in kernel.InvokePromptStreamingAsync<StreamingChatMessageContent>(prompt))
+        {
+            if (!roleWritten && chatUpdate.Role.HasValue)
+            {
+                Console.Write($"{chatUpdate.Role.Value}: {chatUpdate.Content}");
+                roleWritten = true;
+            }
+
+            if (chatUpdate.Content is { Length: > 0 })
+            {
+                fullMessage += chatUpdate.Content;
+                Console.Write(chatUpdate.Content);
+            }
+        }
+
+        Console.WriteLine("\n------------------------");
+        return fullMessage;
+    }
+
+    /// <summary>
+    /// Outputs the last message of the chat history
+    /// </summary>
+    private void OutputLastMessage(ChatHistory chatHistory)
+    {
+        var message = chatHistory.Last();
+
+        Console.WriteLine($"{message.Role}: {message.Content}");
+        Console.WriteLine("------------------------");
+    }
+}

dotnet/samples/Concepts/Concepts.csproj

@@ -63,6 +63,7 @@
     <ProjectReference Include="..\..\src\Connectors\Connectors.Memory.Redis\Connectors.Memory.Redis.csproj" />
     <ProjectReference Include="..\..\src\Connectors\Connectors.Memory.Sqlite\Connectors.Memory.Sqlite.csproj" />
     <ProjectReference Include="..\..\src\Connectors\Connectors.Memory.Weaviate\Connectors.Memory.Weaviate.csproj" />
+    <ProjectReference Include="..\..\src\Connectors\Connectors.Ollama\Connectors.Ollama.csproj" />
     <ProjectReference Include="..\..\src\Connectors\Connectors.OpenAI\Connectors.OpenAI.csproj" />
     <ProjectReference Include="..\..\src\Experimental\Agents\Experimental.Agents.csproj" />
     <ProjectReference Include="..\..\src\Experimental\Orchestration.Flow\Experimental.Orchestration.Flow.csproj" />

dotnet/samples/Concepts/Memory/Ollama_EmbeddingGeneration.cs

@@ -0,0 +1,35 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using Microsoft.SemanticKernel;
+using Microsoft.SemanticKernel.Embeddings;
+using xRetry;
+
+#pragma warning disable format // Format item can be simplified
+#pragma warning disable CA1861 // Avoid constant arrays as arguments
+
+namespace Memory;
+
+// The following example shows how to use Semantic Kernel with Ollama API.
+public class Ollama_EmbeddingGeneration(ITestOutputHelper output) : BaseTest(output)
+{
+    [RetryFact(typeof(HttpOperationException))]
+    public async Task RunEmbeddingAsync()
+    {
+        Assert.NotNull(TestConfiguration.Ollama.EmbeddingModelId);
+
+        Console.WriteLine("\n======= Ollama - Embedding Example ========\n");
+
+        Kernel kernel = Kernel.CreateBuilder()
+            .AddOllamaTextEmbeddingGeneration(
+                endpoint: new Uri(TestConfiguration.Ollama.Endpoint),
+                modelId: TestConfiguration.Ollama.EmbeddingModelId)
+            .Build();
+
+        var embeddingGenerator = kernel.GetRequiredService<ITextEmbeddingGenerationService>();
+
+        // Generate embeddings for each chunk.
+        var embeddings = await embeddingGenerator.GenerateEmbeddingsAsync(["John: Hello, how are you?\nRoger: Hey, I'm Roger!"]);
+
+        Console.WriteLine($"Generated {embeddings.Count} embeddings for the provided text");
+    }
+}