From 1088037e5854ee37a082486ef8567e66e061e5e2 Mon Sep 17 00:00:00 2001
From: Sergey Gut <kruzefag@gmail.com>
Date: Sun, 28 Jan 2024 18:51:18 +0300
Subject: [PATCH] Initial webhook support

---
 Core/Controllers/Telegram.cs  | 75 +++++++++++++++++++++++++++++++++++
 Core/Core.csproj              |  2 +-
 Core/Startup.cs               | 10 ++++-
 Core/WebhookAspNetProvider.cs | 40 +++++++++++++++++++
 4 files changed, 125 insertions(+), 2 deletions(-)
 create mode 100644 Core/Controllers/Telegram.cs
 create mode 100644 Core/WebhookAspNetProvider.cs

diff --git a/Core/Controllers/Telegram.cs b/Core/Controllers/Telegram.cs
new file mode 100644
index 0000000..21ac958
--- /dev/null
+++ b/Core/Controllers/Telegram.cs
@@ -0,0 +1,75 @@
+using BotFramework.Abstractions.UpdateProvider;
+using BotFramework.Config;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+using Newtonsoft.Json;
+using System.Threading.Tasks;
+using Telegram.Bot;
+using Telegram.Bot.Types;
+
+namespace Kruzya.TelegramBot.Core.Controllers
+{
+    [Route("/Telegram")]
+    public class Telegram : Controller
+    {
+        private const string SecretTokenHeader = "X-Telegram-Bot-Api-Secret-Token";
+
+        private readonly ILogger<Telegram> _logger;
+        private readonly ITelegramBotClient _client;
+        private readonly IUpdateTarget _updateTarget;
+        private readonly string _secretToken;
+
+        public Telegram(ILogger<Telegram> logger, ITelegramBotClient client, IUpdateTarget updateTarget, IOptions<BotConfig> config)
+        {
+            _logger = logger;
+            _client = client;
+            _updateTarget = updateTarget;
+
+            _secretToken = config.Value.Webhook.SecretToken;
+            if (string.IsNullOrEmpty(_secretToken))
+            {
+                _secretToken = null;
+            }
+        }
+
+        [Route("/WebHook")]
+        [HttpPost]
+        public IActionResult Index()
+        {
+            if (_secretToken != null && !Request.Headers.ContainsKey(SecretTokenHeader))
+            {
+                _logger.LogWarning("Someone tried push update without secret key in headers");
+                return BadRequest();
+            }
+
+            var ok = (_secretToken == null || Request.Headers[SecretTokenHeader] == _secretToken);
+            if (!ok)
+            {
+                _logger.LogWarning("Someone tried push update with wrong secret key in headers");
+                return BadRequest();
+            }
+
+            LaunchHandle();
+            return Ok();
+        }
+
+        private void LaunchHandle()
+        {
+            try
+            {
+                var update = JsonConvert.DeserializeObject<Update>(Request.Body.ToString());
+                if (update == null)
+                {
+                    throw new System.Exception("Invalid request body");
+                }
+
+                _updateTarget.Push(update);
+            }
+            catch (System.Exception e)
+            {
+                _logger.LogError($"Error occured when handling a new update: {e}");
+            }
+        }
+    }
+}
diff --git a/Core/Core.csproj b/Core/Core.csproj
index 6413eea..1931408 100644
--- a/Core/Core.csproj
+++ b/Core/Core.csproj
@@ -8,7 +8,7 @@
 
     <PropertyGroup Condition=" '$(RunConfiguration)' == 'Core' " />
     <ItemGroup>
-      <PackageReference Include="AleXr64.BotFramework" Version="2.0.7-g4bee468724" />
+      <PackageReference Include="AleXr64.BotFramework" Version="2.0.8-gf720999661" />
       <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="7.0.1">
         <PrivateAssets>all</PrivateAssets>
         <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
diff --git a/Core/Startup.cs b/Core/Startup.cs
index 672e552..3073ed4 100644
--- a/Core/Startup.cs
+++ b/Core/Startup.cs
@@ -13,6 +13,7 @@ using Microsoft.Extensions.Logging;
 using System.Collections.Concurrent;
 using Kruzya.TelegramBot.Core.Options;
 using Telegram.Bot.Types;
+using BotFramework.Abstractions.UpdateProvider;
 
 namespace Kruzya.TelegramBot.Core;
 
@@ -49,7 +50,8 @@ public class Startup
         services.AddSingleton<IAntiFlood, MemoryAntiFloodService>();
 
         services.AddSingleton<ThreadSafeRandom>();
-
+        services.AddSingleton<IWebhookProvider, WebhookAspNetProvider>();
+        services.AddControllersWithViews();
 
         services.AddSingleton<ConcurrentBag<DeleteRequest>>();
         services.AddHostedService<DeleteService>();
@@ -64,6 +66,12 @@ public class Startup
     // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
     public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
     {
+        app.UseRouting();
+        app.UseEndpoints(endpoints =>
+        {
+            endpoints.MapControllers();
+        });
+
         _core.Modules.Configure(app, env);
     }
 }
\ No newline at end of file
diff --git a/Core/WebhookAspNetProvider.cs b/Core/WebhookAspNetProvider.cs
new file mode 100644
index 0000000..fe13169
--- /dev/null
+++ b/Core/WebhookAspNetProvider.cs
@@ -0,0 +1,40 @@
+#nullable enable
+
+using BotFramework.Abstractions.UpdateProvider;
+using BotFramework.Config;
+using Microsoft.Extensions.Options;
+using System.Threading;
+using System.Threading.Tasks;
+using Telegram.Bot;
+
+namespace Kruzya.TelegramBot.Core
+{
+    public class WebhookAspNetProvider : IWebhookProvider
+    {
+        private readonly ITelegramBotClient _client;
+        private readonly BotConfig _config;
+        private readonly string? _secretToken;
+
+        public WebhookAspNetProvider(ITelegramBotClient client, IOptions<BotConfig> config)
+        {
+            _client = client;
+            _config = config.Value;
+
+            _secretToken = _config.Webhook.SecretToken;
+            if (string.IsNullOrWhiteSpace(_secretToken))
+            {
+                _secretToken = null;
+            }
+        }
+
+        public async Task StartAsync(CancellationToken token)
+        {
+            await _client.SetWebhookAsync(_config.Webhook.Url, secretToken: _secretToken, cancellationToken: token);
+        }
+
+        public async Task StopAsync(CancellationToken token)
+        {
+            await _client.DeleteWebhookAsync(cancellationToken: token);
+        }
+    }
+}