Load JSON based NLog config (e.g. declared in appsettings.json) + Beg…

…inScopeParser performance improvements (#263)

* Load NLog config from appsettings.json using NLogLoggingConfiguration

* Update NLog.Extensions.Logging.csproj

* refactor

NLog.Extensions.Logging.sln

@@ -8,6 +8,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 	ProjectSection(SolutionItems) = preProject
 		appveyor.yml = appveyor.yml
 		build.ps1 = build.ps1
+		CHANGELOG.MD = CHANGELOG.MD
 		README.md = README.md
 	EndProjectSection
 EndProject

build.ps1

@@ -2,8 +2,8 @@
 # creates NuGet package at \artifacts
 dotnet --version
 
-$versionPrefix = "1.4.0"
-$versionSuffix = ""
+$versionPrefix = "1.5.0"
+$versionSuffix = "rc1"
 $versionFile = $versionPrefix + "." + ${env:APPVEYOR_BUILD_NUMBER}
 $versionProduct = $versionPrefix;
 if (-Not $versionSuffix.Equals(""))

examples/NetCore2/ConsoleExample/ConsoleExample.csproj

@@ -11,7 +11,6 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="2.1.0" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="2.1.0" />
-    <PackageReference Include="NLog.Schema" Version="4.5.11" />
   </ItemGroup>
 
   <ItemGroup>

examples/NetCore2/ConsoleExample/Program.cs

@@ -12,13 +12,16 @@ internal class Program
         private static void Main()
         {
             var logger = LogManager.GetCurrentClassLogger();
+
             try
             {
                 var config = new ConfigurationBuilder()
                     .SetBasePath(System.IO.Directory.GetCurrentDirectory())
                     .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
                     .Build();
 
+                LogManager.Configuration = new NLogLoggingConfiguration(config.GetSection("NLog"));
+
                 var servicesProvider = BuildDi(config);
                 using (servicesProvider as IDisposable)
                 {

examples/NetCore2/ConsoleExample/appsettings.json

@@ -5,5 +5,43 @@
             "ParseMessageTemplates": true,
             "CaptureMessageProperties": true
         }
+    },
+    "NLog": {
+        "autoreload": true,
+        "internalLogLevel": "Info",
+        "internalLogFile": "c:/temp/console-example-internal.log",
+        "throwConfigExceptions": true,
+        "targets": {
+            "console": {
+                "type": "Console",
+                "layout": "${date}|${level:uppercase=true}|${message} ${exception:format=tostring}|${logger}|${all-event-properties}"
+            },
+            "file": {
+                "type": "AsyncWrapper",
+                "target": {
+                    "wrappedFile": {
+                        "type": "File",
+                        "fileName": "c:/temp/console-example.log",
+                        "layout": {
+                            "type": "JsonLayout",
+                            "Attributes": [
+                                { "name": "timestamp", "layout": "${date:format=o}" },
+                                { "name": "level", "layout": "${level}" },
+                                { "name": "logger", "layout": "${logger}" },
+                                { "name": "message", "layout": "${message:raw=true}" },
+                                { "name": "properties", "encode": false, "layout": { "type": "JsonLayout", "includeallproperties": "true" } }
+                            ]
+                        }
+                    }
+                }
+            }
+        },
+        "rules": [
+            {
+                "logger": "*",
+                "minLevel": "Trace",
+                "writeTo": "File,Console"
+            }
+        ]
     }
 }

src/NLog.Extensions.Logging/Config/NLogLoggingConfiguration.cs

@@ -0,0 +1,112 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.Extensions.Configuration;
+using NLog.Config;
+
+namespace NLog.Extensions.Logging
+{
+    /// <summary>
+    /// Configures NLog through Microsoft Extension Configuration section (Ex from appsettings.json)
+    /// </summary>
+    public class NLogLoggingConfiguration : LoggingConfigurationParser
+    {
+        private readonly Action<object> _reloadConfiguration;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="NLogLoggingConfiguration"/> class. 
+        /// </summary>
+        /// <param name="nlogConfig">Configuration section to be read</param>
+        public NLogLoggingConfiguration(IConfigurationSection nlogConfig)
+            : this(nlogConfig, LogManager.LogFactory)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="NLogLoggingConfiguration"/> class. 
+        /// </summary>
+        /// <param name="nlogConfig">Configuration section to be read</param>
+        /// <param name="logFactory">The <see cref="LogFactory"/> to which to apply any applicable configuration values.</param>
+        public NLogLoggingConfiguration(IConfigurationSection nlogConfig, LogFactory logFactory)
+            : base(logFactory)
+        {
+            _reloadConfiguration = (state) => LoadConfigurationSection((IConfigurationSection)state, true);
+            LoadConfigurationSection(nlogConfig, null);
+        }
+
+        private void LoadConfigurationSection(IConfigurationSection nlogConfig, bool? autoReload)
+        {
+            var configElement = new LoggingConfigurationElement(nlogConfig, true);
+            LoadConfig(configElement, null);
+            if (autoReload ?? configElement.AutoReload)
+            {
+                nlogConfig.GetReloadToken().RegisterChangeCallback(_reloadConfiguration, nlogConfig);
+            }
+        }
+
+        private class LoggingConfigurationElement : ILoggingConfigurationElement
+        {
+            readonly IConfigurationSection _configurationSection;
+            readonly string _nameOverride;
+
+            public bool AutoReload { get; }
+
+            public LoggingConfigurationElement(IConfigurationSection configurationSection, bool topElement, string nameOverride = null)
+            {
+                _configurationSection = configurationSection;
+                _nameOverride = nameOverride;
+                if (topElement && bool.TryParse(configurationSection["autoreload"], out var autoreload))
+                {
+                    AutoReload = autoreload;
+                }
+            }
+
+            public string Name => _nameOverride ?? _configurationSection.Key;
+
+            public IEnumerable<KeyValuePair<string, string>> Values
+            {
+                get
+                {
+                    var children = _configurationSection.GetChildren();
+                    foreach (var child in children)
+                    {
+                        if (!child.GetChildren().Any())
+                            yield return new KeyValuePair<string, string>(child.Key, child.Value);
+                    }
+                    if (_nameOverride != null)
+                        yield return new KeyValuePair<string, string>("name", _configurationSection.Key);
+                }
+            }
+
+            public IEnumerable<ILoggingConfigurationElement> Children
+            {
+                get
+                {
+                    var children = _configurationSection.GetChildren();
+                    foreach (var child in children)
+                    {
+                        var firstChildValue = child?.GetChildren()?.FirstOrDefault();
+                        if (firstChildValue == null)
+                        {
+                            continue;
+                        }
+
+                        if (_nameOverride == "target" && child.Key.EqualsOrdinalIgnoreCase("target") && child.GetChildren().Count() == 1)
+                        {
+                            yield return new LoggingConfigurationElement(firstChildValue, false, "target");
+                        }
+                        else
+                        {
+                            string nameOverride = null;
+                            if (_configurationSection.Key.EqualsOrdinalIgnoreCase("targets"))
+                            {
+                                nameOverride = "target";
+                            }
+                            yield return new LoggingConfigurationElement(child, false, nameOverride);
+                        }
+                    }
+                }
+            }
+        }
+    }
+}

src/NLog.Extensions.Logging/Internal/StringExtensions.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Linq;
+
+namespace NLog.Extensions.Logging
+{
+    internal static class StringExtensions
+    {
+        internal static bool EqualsOrdinalIgnoreCase(this string text, string text2)
+        {
+            return string.Equals(text, text2, StringComparison.OrdinalIgnoreCase);
+        }
+    }
+}