New: Telegram notifications

Closes #1355

src/NzbDrone.Core/Notifications/Telegram/InvalidResponseException.cs

@@ -0,0 +1,15 @@
+using System;
+
+namespace NzbDrone.Core.Notifications.Telegram
+{
+    public class InvalidResponseException : Exception
+    {
+        public InvalidResponseException()
+        {
+        }
+
+        public InvalidResponseException(string message) : base(message)
+        {
+        }
+    }
+}

src/NzbDrone.Core/Notifications/Telegram/Telegram.cs

@@ -0,0 +1,65 @@
+using System.Collections.Generic;
+using FluentValidation.Results;
+using NzbDrone.Common.Extensions;
+using NzbDrone.Core.Tv;
+
+namespace NzbDrone.Core.Notifications.Telegram
+{
+    public class Telegram : NotificationBase<TelegramSettings>
+    {
+        private readonly ITelegramProxy _proxy;
+
+        public Telegram(ITelegramProxy proxy)
+        {
+            _proxy = proxy;
+        }
+
+        public override string Link
+        {
+            get { return "https://telegram.org/"; }
+        }
+
+        public override void OnGrab(GrabMessage grabMessage)
+        {
+            const string title = "Episode Grabbed";
+
+            _proxy.SendNotification(title, grabMessage.Message, Settings);
+        }
+
+        public override void OnDownload(DownloadMessage message)
+        {
+            const string title = "Episode Downloaded";
+
+            _proxy.SendNotification(title, message.Message, Settings);
+        }
+
+        public override void OnRename(Series series)
+        {
+        }
+
+        public override string Name
+        {
+            get
+            {
+                return "Telegram";
+            }
+        }
+
+        public override bool SupportsOnRename
+        {
+            get
+            {
+                return false;
+            }
+        }
+
+        public override ValidationResult Test()
+        {
+            var failures = new List<ValidationFailure>();
+
+            failures.AddIfNotNull(_proxy.Test(Settings));
+
+            return new ValidationResult(failures);
+        }
+    }
+}

src/NzbDrone.Core/Notifications/Telegram/TelegramError.cs

@@ -0,0 +1,14 @@
+using Newtonsoft.Json;
+
+namespace NzbDrone.Core.Notifications.Telegram
+{
+    public class TelegramError
+    {
+        public bool Ok { get; set; }
+
+        [JsonProperty(PropertyName = "error_code")]
+        public int ErrorCode { get; set; }
+
+        public string Description { get; set; }
+    }
+}

src/NzbDrone.Core/Notifications/Telegram/TelegramService.cs

@@ -0,0 +1,72 @@
+using System;
+using System.Net;
+using FluentValidation.Results;
+using NLog;
+using NzbDrone.Common.Extensions;
+using NzbDrone.Common.Serializer;
+using RestSharp;
+using NzbDrone.Core.Rest;
+
+namespace NzbDrone.Core.Notifications.Telegram
+{
+    public interface ITelegramProxy
+    {
+        void SendNotification(string title, string message, TelegramSettings settings);
+        ValidationFailure Test(TelegramSettings settings);
+    }
+
+    public class TelegramProxy : ITelegramProxy
+    {
+        private readonly Logger _logger;
+        private const string URL = "https://api.telegram.org";
+
+        public TelegramProxy(Logger logger)
+        {
+            _logger = logger;
+        }
+
+        public void SendNotification(string title, string message, TelegramSettings settings)
+        {
+            //Format text to add the title before and bold using markdown
+            var text = $"*{title}*\n{message}";
+            var client = RestClientFactory.BuildClient(URL);
+            var request = new RestRequest("bot{token}/sendmessage", Method.POST);
+
+            request.AddUrlSegment("token", settings.BotToken);
+            request.AddParameter("chat_id", settings.ChatId);
+            request.AddParameter("parse_mode", "Markdown");
+            request.AddParameter("text", text);
+
+            client.ExecuteAndValidate(request);
+        }
+
+        public ValidationFailure Test(TelegramSettings settings)
+        {
+            try
+            {
+                const string title = "Test Notification";
+                const string body = "This is a test message from Sonarr";
+
+                SendNotification(title, body, settings);
+            }
+            catch (Exception ex)
+            {
+                _logger.Error(ex, "Unable to send test message: " + ex.Message);
+
+                var restException = ex as RestException;
+
+                if (restException != null && restException.Response.StatusCode == HttpStatusCode.BadRequest)
+                {
+                    var error = Json.Deserialize<TelegramError>(restException.Response.Content);
+                    var property = error.Description.ContainsIgnoreCase("chat not found") ? "ChatId" : "BotToken";
+
+                    return new ValidationFailure(property, error.Description);
+                }
+
+                return new ValidationFailure("BotToken", "Unable to send test message");
+            }
+
+            return null;
+        }
+    }
+}

src/NzbDrone.Core/Notifications/Telegram/TelegramSettings.cs

@@ -0,0 +1,40 @@
+using FluentValidation;
+using NzbDrone.Core.Annotations;
+using NzbDrone.Core.ThingiProvider;
+using NzbDrone.Core.Validation;
+
+namespace NzbDrone.Core.Notifications.Telegram
+{
+    public class TelegramSettingsValidator : AbstractValidator<TelegramSettings>
+    {
+        public TelegramSettingsValidator()
+        {
+            RuleFor(c => c.BotToken).NotEmpty();
+            RuleFor(c => c.ChatId).NotEmpty();
+        }
+    }
+
+    public class TelegramSettings : IProviderConfig
+    {
+        private static readonly TelegramSettingsValidator Validator = new TelegramSettingsValidator();
+
+        [FieldDefinition(0, Label = "Bot Token", HelpLink = "https://core.telegram.org/bots")]
+        public string BotToken { get; set; }
+
+        [FieldDefinition(1, Label = "Chat ID", HelpLink = "http://stackoverflow.com/a/37396871/882971", HelpText = "You must start a conversation with the bot or add it to your group to receive messages")]
+        public string ChatId { get; set; }
+
+        public bool IsValid
+        {
+            get
+            {
+                return !string.IsNullOrWhiteSpace(ChatId) && !string.IsNullOrWhiteSpace(BotToken);
+            }
+        }
+
+        public NzbDroneValidationResult Validate()
+        {
+            return new NzbDroneValidationResult(Validator.Validate(this));
+        }
+    }
+}

src/NzbDrone.Core/NzbDrone.Core.csproj

@@ -842,6 +842,10 @@
     <Compile Include="Notifications\Synology\SynologyIndexer.cs" />
     <Compile Include="Notifications\Synology\SynologyIndexerProxy.cs" />
     <Compile Include="Notifications\Synology\SynologyIndexerSettings.cs" />
+    <Compile Include="Notifications\Telegram\InvalidResponseException.cs" />
+    <Compile Include="Notifications\Telegram\Telegram.cs" />
+    <Compile Include="Notifications\Telegram\TelegramService.cs" />
+    <Compile Include="Notifications\Telegram\TelegramSettings.cs" />
     <Compile Include="Notifications\Twitter\OAuthToken.cs" />
     <Compile Include="Notifications\Twitter\TwitterException.cs" />
     <Compile Include="Notifications\Webhook\WebhookEpisode.cs" />
@@ -1173,6 +1177,7 @@
       <Link>libsqlite3.0.dylib</Link>
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
+    <Compile Include="Notifications\Telegram\TelegramError.cs" />
   </ItemGroup>
   <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />