Membangun Bot di .NET dengan Bot Framework SDK

# Buat Web API minimal
dotnet new webapi -n DotNetBot
cd DotNetBot

# Tambah paket Bot Framework
dotnet add package Microsoft.Bot.Builder
dotnet add package Microsoft.Bot.Builder.Integration.AspNet.Core

# (Opsional) dialog, LUIS/recognizer
dotnet add package Microsoft.Bot.Builder.Dialogs
dotnet add package Microsoft.Bot.Builder.AI.Luis

using Microsoft.Bot.Builder.Integration.AspNet.Core;
using Microsoft.Bot.Builder;
using Microsoft.Extensions.Logging;

public class AdapterWithErrorHandler : BotFrameworkHttpAdapter
{
    public AdapterWithErrorHandler(ILogger<BotFrameworkHttpAdapter> logger)
    {
        OnTurnError = async (turnContext, exception) =>
        {
            logger.LogError(exception, "Bot error");
            await turnContext.SendActivityAsync("Maaf, terjadi error. Coba lagi.");
        };
    }
}

using Microsoft.AspNetCore.Mvc;
using Microsoft.Bot.Builder;
using Microsoft.Bot.Builder.Integration.AspNet.Core;

[ApiController]
[Route("api/messages")]
public class BotController : ControllerBase
{
    private readonly IBot _bot;
    private readonly BotFrameworkHttpAdapter _adapter;

    public BotController(BotFrameworkHttpAdapter adapter, IBot bot)
    {
        _adapter = adapter;
        _bot = bot;
    }

    [HttpPost, HttpGet]
    public async Task PostAsync()
        => await _adapter.ProcessAsync(Request, Response, _bot);
}

using Microsoft.Bot.Builder;
using Microsoft.Bot.Schema;

public class EchoBot : ActivityHandler
{
    protected override async Task OnMessageActivityAsync(ITurnContext<IMessageActivity> context, CancellationToken ct)
    {
        var text = context.Activity.Text?.Trim();
        await context.SendActivityAsync(MessageFactory.Text($"Kamu berkata: {text}"), ct);
    }

    protected override async Task OnMembersAddedAsync(IList<ChannelAccount> membersAdded, ITurnContext<IConversationUpdateActivity> context, CancellationToken ct)
    {
        foreach (var m in membersAdded)
            if (m.Id != context.Activity.Recipient?.Id)
                await context.SendActivityAsync("Halo! Kirim pesan apa saja dan akan saya echo.", ct: ct);
    }
}

var builder = WebApplication.CreateBuilder(args);

// Adapter + Bot
builder.Services.AddSingleton<BotFrameworkHttpAdapter, AdapterWithErrorHandler>();
builder.Services.AddSingleton<IBot, EchoBot>();

// State (in-memory untuk dev)
using Microsoft.Bot.Builder;
using Microsoft.Bot.Builder.MemoryStorage;
var storage = new MemoryStorage();
builder.Services.AddSingleton<IStorage>(storage);
builder.Services.AddSingleton<UserState>();
builder.Services.AddSingleton<ConversationState>();

var app = builder.Build();
app.MapControllers();
app.Run();

public class EchoBot : ActivityHandler
{
    private readonly UserState _userState;
    private readonly ConversationState _convState;
    private readonly IStatePropertyAccessor<string> _nameAccessor;

    public EchoBot(UserState userState, ConversationState convState)
    {
        _userState = userState;
        _convState = convState;
        _nameAccessor = _userState.CreateProperty<string>("name");
    }

    protected override async Task OnMessageActivityAsync(ITurnContext<IMessageActivity> context, CancellationToken ct)
    {
        var text = context.Activity.Text?.Trim().ToLowerInvariant();
        var name = await _nameAccessor.GetAsync(context, () => string.Empty, ct);

        if (text?.StartsWith("set nama ") == true)
        {
            name = text.Substring("set nama ".Length);
            await _nameAccessor.SetAsync(context, name, ct);
            await context.SendActivityAsync($"Nama disimpan: {name}", ct: ct);
        }
        else
        {
            await context.SendActivityAsync($"Hai {name or 'teman'} — kamu berkata: {context.Activity.Text}", ct: ct);
        }

        await _userState.SaveChangesAsync(context, false, ct);
        await _convState.SaveChangesAsync(context, false, ct);
    }
}

using Microsoft.Bot.Builder.Dialogs;

public class ProfileDialog : ComponentDialog
{
    public ProfileDialog() : base(nameof(ProfileDialog))
    {
        var steps = new WaterfallStep[]
        {
            async (step, ct) => { return await step.PromptAsync("name", new PromptOptions{ Prompt = MessageFactory.Text("Siapa namamu?") }, ct); },
            async (step, ct) => { var name = (string)step.Result; await step.Context.SendActivityAsync($"Halo {name}!", ct: ct); return await step.EndDialogAsync(null, ct); }
        };
        AddDialog(new TextPrompt("name"));
        AddDialog(new WaterfallDialog(nameof(WaterfallDialog), steps));
        InitialDialogId = nameof(WaterfallDialog);
    }
}

// Pseudo: panggil recognizer lalu route intent
var (intent, score) = await RecognizeIntentAsync(context.Activity.Text);
if (intent == "Help") { await context.SendActivityAsync("Perintah: set nama <teks>, help, bye"); }
else if (intent == "Bye") { await context.SendActivityAsync("Sampai jumpa!"); }