Text completion 2. (Legacy)

WARNING! - This is a legacy feature of OpenAI, it will be shut down on January 4th, 2024. Check more information: https://platform.openai.com/docs/api-reference/completions

The next example demonstrates, how you can receive an answer in streamed mode. Streamed mode means, you will get the generated answer in pieces and not in one packages like in the previous example. Because of generating an answer takes time, it can be useful, if you see the result in the meantime. The process also can be cancelled.

This version works with a callback. It will be called each time, if a piece of answer arrived.

public static async Task Main(string[] args)
{
    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>()!;

    // this method is useful for older .NET where the IAsyncEnumerable is not supported,
    // or you just simply does not prefer this way

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

    Console.WriteLine(request.Prompt);

    Action<HttpOperationResult<TextCompletionResponse>> receivedDataHandler = 
        (HttpOperationResult<TextCompletionResponse> response) => 
    {
        if (response.IsSuccess)
        {
            Console.Write(response.Result?.Completions[0].Text);
        }
        else
        {
            Console.WriteLine(response);
        }
    };

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

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

}