Webhook support (#179)

* feat: internal update processing redesign

* feat: initial webhook implementation

* refactor: IUpdateSource -> IUpdateTarget, move queue to instance

also return option to turn webhooks on/off in config

* Properly stop

* fix: wait until update thread stops & code cleanup

* feat(webhook): secret token support

---------

Co-authored-by: Alexander <[email protected]>

TGBotFramework/BotFramework.Tests/BotFramework.Tests.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>
@@ -7,7 +7,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="6.0.0" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="7.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">

TGBotFramework/BotFramework.Webhook/BotFramework.Webhook.csproj

@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netstandard2.1</TargetFramework>
+    <Nullable>enable</Nullable>
+    <LangVersion>latestMajor</LangVersion>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Watson" Version="6.0.2" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\BotFramework\BotFramework.csproj" />
+  </ItemGroup>
+
+</Project>

TGBotFramework/BotFramework.Webhook/ServiceCollectionExtensions.cs

@@ -0,0 +1,18 @@
+using BotFramework.Abstractions.UpdateProvider;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace BotFramework.Webhook;
+
+public static class ServiceCollectionExtensions
+{
+    public static void AddTelegramBotWebhookUpdateProvider(this IServiceCollection collection)
+    {
+        collection.AddSingleton<IWebhookProvider, WebhookUpdateProvider>();
+    }
+
+    public static void AddTelegramBotWebhook(this IServiceCollection collection)
+    {
+        collection.AddTelegramBotWebhookUpdateProvider();
+        collection.AddTelegramBot();
+    }
+}

TGBotFramework/BotFramework.Webhook/WebhookUpdateProvider.cs

@@ -0,0 +1,85 @@
+using System;
+using System.Net;
+using System.Threading;
+using System.Threading.Tasks;
+using BotFramework.Abstractions.UpdateProvider;
+using BotFramework.Config;
+using Microsoft.Extensions.Options;
+using Newtonsoft.Json;
+using Telegram.Bot;
+using Telegram.Bot.Types;
+using WatsonWebserver.Core;
+
+namespace BotFramework.Webhook;
+
+public class WebhookUpdateProvider : IWebhookProvider
+{
+    private const string SecretTokenHeader = "X-Telegram-Bot-Api-Secret-Token";
+
+    private readonly ITelegramBotClient _client;
+    private readonly IUpdateTarget _updateTarget;
+    private readonly BotConfig _config;
+
+    private readonly string? _secretToken;
+
+    private readonly CancellationTokenSource _canRunTokenSource = new ();
+
+    public WebhookUpdateProvider(ITelegramBotClient client, IUpdateTarget updateTarget, IOptions<BotConfig> config)
+    {
+        _client = client;
+        _updateTarget = updateTarget;
+        _config = config.Value;
+
+        _secretToken = _config.Webhook.SecretToken;
+        if (string.IsNullOrWhiteSpace(_secretToken))
+        {
+            _secretToken = null;
+        }
+    }
+
+    public async Task StartAsync(CancellationToken token)
+    {
+        token.ThrowIfCancellationRequested();
+        var server = new WatsonWebserver.Webserver(GetWebserverSettings(), Route);
+        _ = server.StartAsync(_canRunTokenSource.Token);
+
+        await _client.SetWebhookAsync(_config.Webhook.Url, secretToken: _secretToken, cancellationToken: token);
+    }
+
+    public async Task StopAsync(CancellationToken token)
+    {
+        _canRunTokenSource.Cancel();
+        await _client.DeleteWebhookAsync(cancellationToken: token);
+    }
+
+    private async Task Route(HttpContextBase ctx)
+    {
+        var request = ctx.Request;
+        if (_secretToken != null && request.RetrieveHeaderValue(SecretTokenHeader) != _secretToken)
+        {
+            ctx.Response.StatusCode = (int)HttpStatusCode.Forbidden;
+
+            await ctx.Response.Send("Missing or invalid secret_token");
+            return;
+        }
+
+        try
+        {
+            var obj = JsonConvert.DeserializeObject<Update>(request.DataAsString);
+            if (obj != null)
+            {
+                _updateTarget.Push(obj);
+            }
+        } catch(Exception e)
+        {
+            Console.WriteLine(e);
+        }
+
+        await ctx.Response.Send();
+    }
+
+    private WebserverSettings GetWebserverSettings()
+    {
+        return new WebserverSettings(_config.Webhook.Host, _config.Webhook.Port);
+    }
+}

TGBotFramework/BotFramework/Abstractions/UpdateProvider/IUpdateProvider.cs

@@ -0,0 +1,10 @@
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace BotFramework.Abstractions.UpdateProvider;
+
+public interface IUpdateProvider
+{
+    Task StartAsync(CancellationToken token);
+    Task StopAsync(CancellationToken token);
+}

TGBotFramework/BotFramework/Abstractions/UpdateProvider/IUpdateTarget.cs

@@ -0,0 +1,8 @@
+using Telegram.Bot.Types;
+
+namespace BotFramework.Abstractions.UpdateProvider;
+
+public interface IUpdateTarget
+{
+    public void Push(Update update);
+}

TGBotFramework/BotFramework/Abstractions/UpdateProvider/IWebhookProvider.cs

@@ -0,0 +1,6 @@
+namespace BotFramework.Abstractions.UpdateProvider;
+
+public interface IWebhookProvider: IUpdateProvider
+{
+
+}