Chat completion

The next code demonstrates how the latest chat function works. Given a chat conversation, the model will return a chat completion response.

static async Task Main(string[] args)
{
    // This example demonstrates, how to make a simple conversation with ChatGPT
    //
    // The very first step to create an account at OpenAI: https://platform.openai.com/
    // Using the loggedIn account, navigate to https://platform.openai.com/account/api-keys
    // Here you can create apiKey(s)

    using var host = Host.CreateDefaultBuilder(args)
        .ConfigureServices((builder, services) =>
        {
            services.AddForgeOpenAI(options =>
            {
                options.AuthenticationInfo = builder.Configuration["OpenAI:ApiKey"]!;
            });
        })
        .Build();

    IOpenAIService openAi = host.Services.GetService<IOpenAIService>()!;

    await ChatWithNonStreamingModeAsync(openAi);

    await ChatWithStreamingModeWithCallback(openAi);

    await ChatWithStreamingMode(openAi);
}

static async Task ChatWithNonStreamingModeAsync(IOpenAIService openAi)
{
    // in this scenario the answer generated on server side, 
    // than the whole chat message will be sent in one pass

    ChatCompletionRequest request = new ChatCompletionRequest(
        ChatMessage
            .CreateFromUser("Count to 20, with a comma between each number and no newlines. E.g., 1, 2, 3, ..."));

    HttpOperationResult<ChatCompletionResponse> response = 
        await openAi.ChatCompletionService
            .GetAsync(request, CancellationToken.None).ConfigureAwait(false);
    
    if (response.IsSuccess)
    {
        Console.WriteLine();
        response.Result!.Choices.ForEach(c => Console.WriteLine(c.Message.Content));

        Console.WriteLine();

        // store the chat message id, which will be used for the next request
        request.Messages.Add(response.Result!.Choices[0].Message);

        // next chat message
        request.Messages.Add(
            ChatMessage.CreateFromUser("Please count from 21 to 30, on the same way than previously."));

        response = await openAi.ChatCompletionService
            .GetAsync(request, CancellationToken.None).ConfigureAwait(false);
        
        if (response.IsSuccess)
        {
            response.Result!.Choices.ForEach(c => Console.WriteLine(c.Message.Content));
        }
        else
        {
            Console.WriteLine(response);
        }
    }
    else
    {
        Console.WriteLine(response);
    }
}

static async Task ChatWithStreamingModeWithCallback(IOpenAIService openAi)
{
    // this method is useful for older .NET where the IAsyncEnumerable is not supported

    ChatCompletionRequest request = new ChatCompletionRequest(
        ChatMessage.CreateFromUser("Write a C# code which demonstrate how to open a text file and read its content"));
    request.MaxTokens = 4096 - request.Messages[0].Content.Split(" ", StringSplitOptions.RemoveEmptyEntries).Length - 100; // calculating max token
    request.Temperature = 0.1; // lower value means more precise answer

    Console.WriteLine(request.Messages[0].Content);

    Action<HttpOperationResult<ChatCompletionStreamedResponse>> receivedDataHandler = (HttpOperationResult<ChatCompletionStreamedResponse> response) =>
    {
        if (response.IsSuccess)
        {
            Console.Write(response.Result?.Choices[0].Delta.Content);
        }
        else
        {
            Console.WriteLine(response);
        }
    };

    HttpOperationResult response = 
        await openAi
            .ChatCompletionService
            .GetStreamAsync(request, receivedDataHandler, CancellationToken.None)
            .ConfigureAwait(false);

    if (response.IsSuccess)
    {
        Console.WriteLine();
    }
    else
    {
        Console.WriteLine(response);
    }
}

static async Task ChatWithStreamingMode(IOpenAIService openAi)
{
    Console.ReadKey();

    ChatCompletionRequest request = new ChatCompletionRequest(ChatMessage.CreateFromUser("Write a C# code which demonstrate how to write some text into file"));
    request.MaxTokens = 4096 - request.Messages[0].Content.Split(" ", StringSplitOptions.RemoveEmptyEntries).Length - 100; // calculating max token
    request.Temperature = 0.1; // lower value means more precise answer

    Console.WriteLine(request.Messages[0].Content);

    await foreach (HttpOperationResult<ChatCompletionStreamedResponse> response in 
        openAi.ChatCompletionService.GetStreamAsync(request, CancellationToken.None))
    {
        if (response.IsSuccess)
        {
            Console.Write(response.Result?.Choices[0].Delta.Content);
        }
        else
        {
            Console.WriteLine(response);
        }
    }

}