New: Added UDP syslog support

(cherry picked from commit 8d856b2edb8bf46a2b516d5f7644ae3fa1151323)

src/Directory.Packages.props

@@ -30,6 +30,7 @@
     <PackageVersion Include="Newtonsoft.Json" Version="13.0.1" />
     <PackageVersion Include="NLog.Extensions.Logging" Version="1.7.4" />
     <PackageVersion Include="NLog" Version="4.7.14" />
+    <PackageVersion Include="NLog.Targets.Syslog" Version="6.0.2" />
     <PackageVersion Include="NUnit3TestAdapter" Version="4.2.1" />
     <PackageVersion Include="NUnit" Version="3.13.2" />
     <PackageVersion Include="NunitXml.TestLogger" Version="3.0.117" />
@@ -60,4 +61,4 @@
     <PackageVersion Include="TagLibSharp-Lidarr" Version="2.2.0.19" />
     <PackageVersion Include="Unity" Version="5.11.10" />
   </ItemGroup>
-</Project>
+</Project>

src/NzbDrone.Core/Configuration/ConfigFileProvider.cs

@@ -44,6 +44,8 @@ namespace NzbDrone.Core.Configuration
         bool UpdateAutomatically { get; }
         UpdateMechanism UpdateMechanism { get; }
         string UpdateScriptPath { get; }
+        string SyslogServer { get; }
+        int SyslogPort { get; }
     }
 
     public class ConfigFileProvider : IConfigFileProvider
@@ -209,6 +211,9 @@ namespace NzbDrone.Core.Configuration
 
         public string UpdateScriptPath => GetValue("UpdateScriptPath", "", false);
 
+        public string SyslogServer => GetValue("SyslogServer", "", persist: false);
+        public int SyslogPort => GetValueInt("SyslogPort", 514, persist: false);
+
         public int GetValueInt(string key, int defaultValue, bool persist = true)
         {
             return Convert.ToInt32(GetValue(key, defaultValue, persist));

src/NzbDrone.Core/Instrumentation/ReconfigureLogging.cs

@@ -2,6 +2,8 @@ using System.Collections.Generic;
 using System.Linq;
 using NLog;
 using NLog.Config;
+using NLog.Targets.Syslog;
+using NLog.Targets.Syslog.Settings;
 using NzbDrone.Common.EnvironmentInfo;
 using NzbDrone.Common.Extensions;
 using NzbDrone.Common.Instrumentation;
@@ -40,6 +42,11 @@ namespace NzbDrone.Core.Instrumentation
                 minimumConsoleLogLevel = LogLevel.Info;
             }
 
+            if (_configFileProvider.SyslogServer.IsNotNullOrWhiteSpace())
+            {
+                SetSyslogParameters(_configFileProvider.SyslogServer, _configFileProvider.SyslogPort, minimumLogLevel);
+            }
+
             var rules = LogManager.Configuration.LoggingRules;
 
             //Console
@@ -101,6 +108,24 @@ namespace NzbDrone.Core.Instrumentation
             }
         }
 
+        private void SetSyslogParameters(string syslogServer, int syslogPort, LogLevel minimumLogLevel)
+        {
+            var syslogTarget = new SyslogTarget();
+
+            syslogTarget.Name = "syslogTarget";
+            syslogTarget.MessageSend.Protocol = ProtocolType.Udp;
+            syslogTarget.MessageSend.Udp.Port = syslogPort;
+            syslogTarget.MessageSend.Udp.Server = syslogServer;
+            syslogTarget.MessageSend.Udp.ReconnectInterval = 500;
+            syslogTarget.MessageCreation.Rfc = RfcNumber.Rfc5424;
+            syslogTarget.MessageCreation.Rfc5424.AppName = BuildInfo.AppName;
+
+            var loggingRule = new LoggingRule("*", minimumLogLevel, syslogTarget);
+
+            LogManager.Configuration.AddTarget("syslogTarget", syslogTarget);
+            LogManager.Configuration.LoggingRules.Add(loggingRule);
+        }
+
         private List<LogLevel> GetLogLevels()
         {
             return new List<LogLevel>

src/NzbDrone.Core/Readarr.Core.csproj

@@ -18,6 +18,7 @@
     <PackageReference Include="MailKit" />
     <PackageReference Include="Newtonsoft.Json" />
     <PackageReference Include="NLog" />
+    <PackageReference Include="NLog.Targets.Syslog" />
     <PackageReference Include="RestSharp" />
     <PackageReference Include="System.IO.Abstractions" />
     <PackageReference Include="TagLibSharp-Lidarr" />