Update doc comments

src/Microsoft.Extensions.Configuration.Abstractions/ConfigurationPath.cs

@@ -11,26 +11,44 @@ namespace Microsoft.Extensions.Configuration
     /// </summary>
     public static class ConfigurationPath
     {
+        /// <summary>
+        /// The delimiter ":" used to separate individual keys in a path.
+        /// </summary>
         public static readonly string KeyDelimiter = ":";
 
-        public static string Combine(params string[] pathSegements)
+        /// <summary>
+        /// Combines path segments into one path.
+        /// </summary>
+        /// <param name="pathSegments">The path segments to combine.</param>
+        /// <returns>The combined path.</returns>
+        public static string Combine(params string[] pathSegments)
         {
-            if (pathSegements == null)
+            if (pathSegments == null)
             {
-                throw new ArgumentNullException(nameof(pathSegements));
+                throw new ArgumentNullException(nameof(pathSegments));
             }
-            return string.Join(KeyDelimiter, pathSegements);
+            return string.Join(KeyDelimiter, pathSegments);
         }
 
-        public static string Combine(IEnumerable<string> pathSegements)
+        /// <summary>
+        /// Combines path segments into one path.
+        /// </summary>
+        /// <param name="pathSegments">The path segments to combine.</param>
+        /// <returns>The combined path.</returns>
+        public static string Combine(IEnumerable<string> pathSegments)
         {
-            if (pathSegements == null)
+            if (pathSegments == null)
             {
-                throw new ArgumentNullException(nameof(pathSegements));
+                throw new ArgumentNullException(nameof(pathSegments));
             }
-            return string.Join(KeyDelimiter, pathSegements);
+            return string.Join(KeyDelimiter, pathSegments);
         }
 
+        /// <summary>
+        /// Extracts the last path segment from the path.
+        /// </summary>
+        /// <param name="path">The path.</param>
+        /// <returns>The last path segment of the path.</returns>
         public static string GetSectionKey(string path)
         {
             if (string.IsNullOrEmpty(path))
@@ -42,6 +60,11 @@ namespace Microsoft.Extensions.Configuration
             return lastDelimiterIndex == -1 ? path : path.Substring(lastDelimiterIndex + 1);
         }
 
+        /// <summary>
+        /// Extracts the path corresponding to the parent node for a given path.
+        /// </summary>
+        /// <param name="path">The path.</param>
+        /// <returns>The original path minus the last individual segment found in it. Null if the original path corresponds to a top level node.</returns>
         public static string GetParentPath(string path)
         {
             if (string.IsNullOrEmpty(path))

src/Microsoft.Extensions.Configuration.Abstractions/IConfiguration.cs

@@ -35,6 +35,10 @@ namespace Microsoft.Extensions.Configuration
         /// <returns>The configuration sub-sections.</returns>
         IEnumerable<IConfigurationSection> GetChildren();
 
+        /// <summary>
+        /// Returns a <see cref="IChangeToken"/> that can be used to observe when this configuration is reloaded.
+        /// </summary>
+        /// <returns>A <see cref="IChangeToken"/>.</returns>
         IChangeToken GetReloadToken();
     }
 }

src/Microsoft.Extensions.Configuration.Abstractions/IConfigurationSource.cs

@@ -14,7 +14,7 @@ namespace Microsoft.Extensions.Configuration
         /// Builds the <see cref="IConfigurationProvider"/> for this source.
         /// </summary>
         /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
-        /// <returns></returns>
+        /// <returns>An <see cref="IConfigurationProvider"/></returns>
         IConfigurationProvider Build(IConfigurationBuilder builder);
     }
 }

src/Microsoft.Extensions.Configuration.Abstractions/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "Abstractions of key-value pair based configuration.\r\nCommonly used types:\r\nMicrosoft.Extensions.Configuration.IConfiguration\r\nMicrosoft.Extensions.Configuration.IConfigurationBuilder\r\nMicrosoft.Extensions.Configuration.IConfigurationProvider\r\nMicrosoft.Extensions.Configuration.IConfigurationRoot\r\nMicrosoft.Extensions.Configuration.IConfigurationSection",

src/Microsoft.Extensions.Configuration.Binder/ConfigurationBinder.cs

@@ -10,8 +10,16 @@ using Microsoft.Extensions.Configuration.Binder;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// Static helper class that allows binding strongly typed objects to configuration values.
+    /// </summary>
     public static class ConfigurationBinder
     {
+        /// <summary>
+        /// Attempts to bind the given object instance to configuration values by matching property names against configuration keys recursively.
+        /// </summary>
+        /// <param name="configuration">The configuration instance to bind.</param>
+        /// <param name="instance">The object to bind.</param>
         public static void Bind(this IConfiguration configuration, object instance)
         {
             if (configuration == null)
@@ -25,21 +33,51 @@ namespace Microsoft.Extensions.Configuration
             }
         }
 
+        /// <summary>
+        /// Extracts the value with the specified key and converts it to type T.
+        /// </summary>
+        /// <typeparam name="T">The type to convert the value to.</typeparam>
+        /// <param name="configuration">The configuration.</param>
+        /// <param name="key">The configuration key for the value to convert.</param>
+        /// <returns>The converted value.</returns>
         public static T GetValue<T>(this IConfiguration configuration, string key)
         {
             return GetValue(configuration, key, default(T));
         }
 
+        /// <summary>
+        /// Extracts the value with the specified key and converts it to type T.
+        /// </summary>
+        /// <typeparam name="T">The type to convert the value to.</typeparam>
+        /// <param name="configuration">The configuration.</param>
+        /// <param name="key">The configuration key for the value to convert.</param>
+        /// <param name="defaultValue">The default value to use if no value is found.</param>
+        /// <returns>The converted value.</returns>
         public static T GetValue<T>(this IConfiguration configuration, string key, T defaultValue)
         {
             return (T)GetValue(configuration, typeof(T), key, defaultValue);
         }
 
+        /// <summary>
+        /// Extracts the value with the specified key and converts it to the specified type.
+        /// </summary>
+        /// <param name="configuration">The configuration.</param>
+        /// <param name="type">The type to convert the value to.</param>
+        /// <param name="key">The configuration key for the value to convert.</param>
+        /// <returns>The converted value.</returns>
         public static object GetValue(this IConfiguration configuration, Type type, string key)
         {
             return GetValue(configuration, type, key, defaultValue: null);
         }
 
+        /// <summary>
+        /// Extracts the value with the specified key and converts it to the specified type.
+        /// </summary>
+        /// <param name="configuration">The configuration.</param>
+        /// <param name="type">The type to convert the value to.</param>
+        /// <param name="key">The configuration key for the value to convert.</param>
+        /// <param name="defaultValue">The default value to use if no value is found.</param>
+        /// <returns>The converted value.</returns>
         public static object GetValue(this IConfiguration configuration, Type type, string key, object defaultValue)
         {
             var value = configuration.GetSection(key).Value;

src/Microsoft.Extensions.Configuration.Binder/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "Functionality to bind an object to data in configuration providers for Microsoft.Extensions.Configuration.",

src/Microsoft.Extensions.Configuration.CommandLine/CommandLineConfigurationExtensions.cs

@@ -6,13 +6,29 @@ using Microsoft.Extensions.Configuration.CommandLine;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// Extension methods for registering <see cref="CommandLineConfigurationProvider"/> with <see cref="IConfigurationBuilder"/>.
+    /// </summary>
     public static class CommandLineConfigurationExtensions
     {
+        /// <summary>
+        /// Adds an <see cref="IConfigurationProvider"/> that reads configuration values from the command line.
+        /// </summary>
+        /// <param name="configurationBuilder">The <see cref="IConfigurationBuilder"/> to add to.</param>
+        /// <param name="args">The command line args.</param>
+        /// <returns>The <see cref="IConfigurationBuilder"/>.</returns>
         public static IConfigurationBuilder AddCommandLine(this IConfigurationBuilder configurationBuilder, string[] args)
         {
             return configurationBuilder.AddCommandLine(args, switchMappings: null);
         }
 
+        /// <summary>
+        /// Adds an <see cref="IConfigurationProvider"/> that reads configuration values from the command line using the specified switch mappings.
+        /// </summary>
+        /// <param name="configurationBuilder">The <see cref="IConfigurationBuilder"/> to add to.</param>
+        /// <param name="args">The command line args.</param>
+        /// <param name="switchMappings">The switch mappings.</param>
+        /// <returns>The <see cref="IConfigurationBuilder"/>.</returns>
         public static IConfigurationBuilder AddCommandLine(
             this IConfigurationBuilder configurationBuilder,
             string[] args,

src/Microsoft.Extensions.Configuration.CommandLine/CommandLineConfigurationProvider.cs

@@ -6,10 +6,18 @@ using System.Collections.Generic;
 
 namespace Microsoft.Extensions.Configuration.CommandLine
 {
+    /// <summary>
+    /// A command line based <see cref="ConfigurationProvider"/>.
+    /// </summary>
     public class CommandLineConfigurationProvider : ConfigurationProvider
     {
         private readonly Dictionary<string, string> _switchMappings;
 
+        /// <summary>
+        /// Initializes a new instance.
+        /// </summary>
+        /// <param name="args">The command line args.</param>
+        /// <param name="switchMappings">The switch mappings.</param>
         public CommandLineConfigurationProvider(IEnumerable<string> args, IDictionary<string, string> switchMappings = null)
         {
             if (args == null)
@@ -25,8 +33,14 @@ namespace Microsoft.Extensions.Configuration.CommandLine
             }
         }
 
+        /// <summary>
+        /// The command line arguments.
+        /// </summary>
         protected IEnumerable<string> Args { get; private set; }
 
+        /// <summary>
+        /// Loads the configuration data from the command line args.
+        /// </summary>
         public override void Load()
         {
             var data = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);

src/Microsoft.Extensions.Configuration.CommandLine/CommandLineConfigurationSource.cs

@@ -5,12 +5,26 @@ using System.Collections.Generic;
 
 namespace Microsoft.Extensions.Configuration.CommandLine
 {
+    /// <summary>
+    /// Represents command line arguments as an <see cref="IConfigurationSource"/>.
+    /// </summary>
     public class CommandLineConfigurationSource : IConfigurationSource
     {
+        /// <summary>
+        /// Gets or sets the switch mappings.
+        /// </summary>
         public IDictionary<string, string> SwitchMappings { get; set; }
 
+        /// <summary>
+        /// Gets or sets the command line args.
+        /// </summary>
         public IEnumerable<string> Args { get; set; }
 
+        /// <summary>
+        /// Builds the <see cref="CommandLineConfigurationProvider"/> for this source.
+        /// </summary>
+        /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
+        /// <returns>A <see cref="CommandLineConfigurationProvider"/></returns>
         public IConfigurationProvider Build(IConfigurationBuilder builder)
         {
             return new CommandLineConfigurationProvider(Args, SwitchMappings);

src/Microsoft.Extensions.Configuration.CommandLine/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "Command line configuration provider implementation for Microsoft.Extensions.Configuration.",

src/Microsoft.Extensions.Configuration.EnvironmentVariables/EnvironmentVariablesConfigurationProvider.cs

@@ -8,6 +8,9 @@ using System.Linq;
 
 namespace Microsoft.Extensions.Configuration.EnvironmentVariables
 {
+    /// <summary>
+    /// An environment variable based <see cref="ConfigurationProvider"/>.
+    /// </summary>
     public class EnvironmentVariablesConfigurationProvider : ConfigurationProvider
     {
         private const string MySqlServerPrefix = "MYSQLCONNSTR_";
@@ -20,15 +23,24 @@ namespace Microsoft.Extensions.Configuration.EnvironmentVariables
 
         private readonly string _prefix;
 
+        /// <summary>
+        /// Initializes a new instance.
+        /// </summary>
         public EnvironmentVariablesConfigurationProvider() : this(string.Empty)
         { }
 
-
+        /// <summary>
+        /// Initializes a new instance with the specified prefix.
+        /// </summary>
+        /// <param name="prefix">A prefix used to filter the environment variables.</param>
         public EnvironmentVariablesConfigurationProvider(string prefix)
         {
             _prefix = prefix ?? string.Empty;
         }
 
+        /// <summary>
+        /// Loads the environment variables.
+        /// </summary>
         public override void Load()
         {
             Load(Environment.GetEnvironmentVariables());

src/Microsoft.Extensions.Configuration.EnvironmentVariables/EnvironmentVariablesConfigurationSource.cs

@@ -1,17 +1,23 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
-using System.Collections;
-using System.Collections.Generic;
-using System.Linq;
-
 namespace Microsoft.Extensions.Configuration.EnvironmentVariables
 {
+    /// <summary>
+    /// Represents environment variables as an <see cref="IConfigurationSource"/>.
+    /// </summary>
     public class EnvironmentVariablesConfigurationSource : IConfigurationSource
     {
+        /// <summary>
+        /// A prefix used to filter environment variables.
+        /// </summary>
         public string Prefix { get; set; }
 
+        /// <summary>
+        /// Builds the <see cref="EnvironmentVariablesConfigurationProvider"/> for this source.
+        /// </summary>
+        /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
+        /// <returns>A <see cref="EnvironmentVariablesConfigurationProvider"/></returns>
         public IConfigurationProvider Build(IConfigurationBuilder builder)
         {
             return new EnvironmentVariablesConfigurationProvider(Prefix);

src/Microsoft.Extensions.Configuration.EnvironmentVariables/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "Environment variables configuration provider implementation for Microsoft.Extensions.Configuration.",

src/Microsoft.Extensions.Configuration.FileExtensions/FileConfigurationExtensions.cs

@@ -6,6 +6,9 @@ using Microsoft.Extensions.FileProviders;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// Extension methods for <see cref="FileConfigurationProvider"/>.
+    /// </summary>
     public static class FileConfigurationExtensions
     {
         private static string FileProviderKey = "FileProvider";

src/Microsoft.Extensions.Configuration.FileExtensions/FileConfigurationProvider.cs

@@ -13,6 +13,10 @@ namespace Microsoft.Extensions.Configuration
     /// </summary>
     public abstract class FileConfigurationProvider : ConfigurationProvider
     {
+        /// <summary>
+        /// Initializes a new instance with the specified source.
+        /// </summary>
+        /// <param name="source">The source settings.</param>
         public FileConfigurationProvider(FileConfigurationSource source)
         {
             if (source == null)
@@ -29,6 +33,9 @@ namespace Microsoft.Extensions.Configuration
             }
         }
 
+        /// <summary>
+        /// The source settings for this provider.
+        /// </summary>
         public FileConfigurationSource Source { get; }
 
         private void Load(bool reload)
@@ -66,6 +73,10 @@ namespace Microsoft.Extensions.Configuration
             Load(reload: false);
         }
 
+        /// <summary>
+        /// Loads this provider's data from a stream.
+        /// </summary>
+        /// <param name="stream">The stream to read.</param>
         public abstract void Load(Stream stream);
     }
 }

src/Microsoft.Extensions.Configuration.FileExtensions/FileConfigurationSource.cs

@@ -30,6 +30,11 @@ namespace Microsoft.Extensions.Configuration
         /// </summary>
         public bool ReloadOnChange { get; set; }
 
+        /// <summary>
+        /// Builds the <see cref="IConfigurationProvider"/> for this source.
+        /// </summary>
+        /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
+        /// <returns>A <see cref="IConfigurationProvider"/></returns>
         public abstract IConfigurationProvider Build(IConfigurationBuilder builder);
     }
 }

src/Microsoft.Extensions.Configuration.FileExtensions/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "Extension methods for configuring file-based configuration providers for Microsoft.Extensions.Configuration.",

src/Microsoft.Extensions.Configuration.Ini/IniConfigurationExtensions.cs

@@ -8,6 +8,9 @@ using Microsoft.Extensions.FileProviders;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// Extension methods for adding <see cref="IniConfigurationProvider"/>.
+    /// </summary>
     public static class IniConfigurationExtensions
     {
         /// <summary>

src/Microsoft.Extensions.Configuration.Ini/IniConfigurationProvider.cs

@@ -21,8 +21,16 @@ namespace Microsoft.Extensions.Configuration.Ini
     /// </examples>
     public class IniConfigurationProvider : FileConfigurationProvider
     {
+        /// <summary>
+        /// Initializes a new instance with the specified source.
+        /// </summary>
+        /// <param name="source">The source settings.</param>
         public IniConfigurationProvider(IniConfigurationSource source) : base(source) { }
 
+        /// <summary>
+        /// Loads the INI data from a stream.
+        /// </summary>
+        /// <param name="stream">The stream to read.</param>
         public override void Load(Stream stream)
         {
             var data = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);

src/Microsoft.Extensions.Configuration.Ini/IniConfigurationSource.cs

@@ -1,12 +1,10 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
-
 namespace Microsoft.Extensions.Configuration.Ini
 {
     /// <summary>
-    /// An INI file based <see cref="IConfigurationSource"/>.
+    /// Represents an INI file as an <see cref="IConfigurationSource"/>.
     /// Files are simple line structures (<a href="http://en.wikipedia.org/wiki/INI_file">INI Files on Wikipedia</a>)
     /// </summary>
     /// <examples>
@@ -19,6 +17,11 @@ namespace Microsoft.Extensions.Configuration.Ini
     /// </examples>
     public class IniConfigurationSource : FileConfigurationSource
     {
+        /// <summary>
+        /// Builds the <see cref="IniConfigurationProvider"/> for this source.
+        /// </summary>
+        /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
+        /// <returns>An <see cref="IniConfigurationProvider"/></returns>
         public override IConfigurationProvider Build(IConfigurationBuilder builder)
         {
             FileProvider = FileProvider ?? builder.GetFileProvider();

src/Microsoft.Extensions.Configuration.Ini/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "INI configuration provider implementation for Microsoft.Extensions.Configuration.",

src/Microsoft.Extensions.Configuration.Json/JsonConfigurationProvider.cs

@@ -14,8 +14,16 @@ namespace Microsoft.Extensions.Configuration.Json
     /// </summary>
     public class JsonConfigurationProvider : FileConfigurationProvider
     {
+        /// <summary>
+        /// Initializes a new instance with the specified source.
+        /// </summary>
+        /// <param name="source">The source settings.</param>
         public JsonConfigurationProvider(JsonConfigurationSource source) : base(source) { }
 
+        /// <summary>
+        /// Loads the JSON data from a stream.
+        /// </summary>
+        /// <param name="stream">The stream to read.</param>
         public override void Load(Stream stream)
         {
             var parser = new JsonConfigurationFileParser();

src/Microsoft.Extensions.Configuration.Json/JsonConfigurationSource.cs

@@ -6,10 +6,15 @@ using System;
 namespace Microsoft.Extensions.Configuration.Json
 {
     /// <summary>
-    /// A JSON file based <see cref="FileConfigurationSource"/>.
+    /// Represents a JSON file as an <see cref="IConfigurationSource"/>.
     /// </summary>
     public class JsonConfigurationSource : FileConfigurationSource
     {
+        /// <summary>
+        /// Builds the <see cref="JsonConfigurationProvider"/> for this source.
+        /// </summary>
+        /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
+        /// <returns>A <see cref="JsonConfigurationProvider"/></returns>
         public override IConfigurationProvider Build(IConfigurationBuilder builder)
         {
             FileProvider = FileProvider ?? builder.GetFileProvider();

src/Microsoft.Extensions.Configuration.Json/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "JSON configuration provider implementation for Microsoft.Extensions.Configuration.",

src/Microsoft.Extensions.Configuration.Xml/XmlConfigurationProvider.cs

@@ -10,16 +10,24 @@ using System.Xml;
 namespace Microsoft.Extensions.Configuration.Xml
 {
     /// <summary>
-    /// An XML file based <see cref="FileConfigurationProvider"/>.
+    /// Represents an XML file as an <see cref="IConfigurationSource"/>.
     /// </summary>
     public class XmlConfigurationProvider : FileConfigurationProvider
     {
         private const string NameAttributeKey = "Name";
 
+        /// <summary>
+        /// Initializes a new instance with the specified source.
+        /// </summary>
+        /// <param name="source">The source settings.</param>
         public XmlConfigurationProvider(XmlConfigurationSource source) : base(source) { }
 
         internal XmlDocumentDecryptor Decryptor { get; set; } = XmlDocumentDecryptor.Instance;
 
+        /// <summary>
+        /// Loads the XML data from a stream.
+        /// </summary>
+        /// <param name="stream">The stream to read.</param>
         public override void Load(Stream stream)
         {
             var data = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);

src/Microsoft.Extensions.Configuration.Xml/XmlConfigurationSource.cs

@@ -1,8 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
-
 namespace Microsoft.Extensions.Configuration.Xml
 {
     /// <summary>
@@ -10,6 +8,11 @@ namespace Microsoft.Extensions.Configuration.Xml
     /// </summary>
     public class XmlConfigurationSource : FileConfigurationSource
     {
+        /// <summary>
+        /// Builds the <see cref="XmlConfigurationProvider"/> for this source.
+        /// </summary>
+        /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
+        /// <returns>A <see cref="XmlConfigurationProvider"/></returns>
         public override IConfigurationProvider Build(IConfigurationBuilder builder)
         {
             FileProvider = FileProvider ?? builder.GetFileProvider();

src/Microsoft.Extensions.Configuration.Xml/XmlDocumentDecryptor.cs

@@ -7,6 +7,9 @@ using System.Xml;
 
 namespace Microsoft.Extensions.Configuration.Xml
 {
+    /// <summary>
+    /// Class responsible for encrypting and decrypting XML.
+    /// </summary>
     public class XmlDocumentDecryptor
     {
         /// <summary>
@@ -18,6 +21,9 @@ namespace Microsoft.Extensions.Configuration.Xml
         public static readonly XmlDocumentDecryptor Instance = new XmlDocumentDecryptor();
 #endif
 
+        /// <summary>
+        /// Initializes a XmlDocumentDecryptor.
+        /// </summary>
         // don't create an instance of this directly
         protected XmlDocumentDecryptor()
         {
@@ -70,6 +76,11 @@ namespace Microsoft.Extensions.Configuration.Xml
             }
         }
 
+        /// <summary>
+        /// Override to process encrypted XML.
+        /// </summary>
+        /// <param name="document">The document.</param>
+        /// <returns>An XmlReader which can read the document.</returns>
         protected virtual XmlReader DecryptDocumentAndCreateXmlReader(XmlDocument document)
         {
             // by default we don't know how to process encrypted XML

src/Microsoft.Extensions.Configuration.Xml/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "XML configuration provider implementation for Microsoft.Extensions.Configuration.",

src/Microsoft.Extensions.Configuration/ConfigurationKeyComparer.cs

@@ -6,12 +6,24 @@ using System.Collections.Generic;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// IComparer implementation used to order configuration keys.
+    /// </summary>
     public class ConfigurationKeyComparer : IComparer<string>
     {
         private static readonly string[] _keyDelimiterArray = new[] { ConfigurationPath.KeyDelimiter };
         
+        /// <summary>
+        /// The default instance.
+        /// </summary>
         public static ConfigurationKeyComparer Instance { get; } = new ConfigurationKeyComparer();
 
+        /// <summary>
+        /// Compares two strings.
+        /// </summary>
+        /// <param name="x">First string.</param>
+        /// <param name="y">Second string.</param>
+        /// <returns></returns>
         public int Compare(string x, string y)
         {
             var xParts = x?.Split(_keyDelimiterArray, StringSplitOptions.RemoveEmptyEntries) ?? new string[0];

src/Microsoft.Extensions.Configuration/ConfigurationProvider.cs

@@ -9,31 +9,60 @@ using Microsoft.Extensions.Primitives;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// Base helper class for implementing an <see cref="IConfigurationProvider"/>
+    /// </summary>
     public abstract class ConfigurationProvider : IConfigurationProvider
     {
         private ConfigurationReloadToken _reloadToken = new ConfigurationReloadToken();
 
+        /// <summary>
+        /// Initializes a new <see cref="IConfigurationProvider"/>
+        /// </summary>
         protected ConfigurationProvider()
         {
             Data = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
         }
 
+        /// <summary>
+        /// The configuration key value pairs for this provider.
+        /// </summary>
         protected IDictionary<string, string> Data { get; set; }
 
+        /// <summary>
+        /// Attempts to find a value with the given key, returns true if one is found, false otherwise.
+        /// </summary>
+        /// <param name="key">The key to lookup.</param>
+        /// <param name="value">The value found at key if one is found.</param>
+        /// <returns>True if key has a value, false otherwise.</returns>
         public virtual bool TryGet(string key, out string value)
         {
             return Data.TryGetValue(key, out value);
         }
 
+        /// <summary>
+        /// Sets a value for a given key.
+        /// </summary>
+        /// <param name="key">The configuration key to set.</param>
+        /// <param name="value">The value to set.</param>
         public virtual void Set(string key, string value)
         {
             Data[key] = value;
         }
 
+        /// <summary>
+        /// Loads (or reloads) the data for this provider.
+        /// </summary>
         public virtual void Load()
         {
         }
        
+        /// <summary>
+        /// Returns the list of keys that this provider has.
+        /// </summary>
+        /// <param name="earlierKeys">The earlier keys that other providers contain.</param>
+        /// <param name="parentPath">The path for the parent IConfiguration.</param>
+        /// <returns>The list of keys for this provider.</returns>
         public virtual IEnumerable<string> GetChildKeys(
             IEnumerable<string> earlierKeys,
             string parentPath)
@@ -53,13 +82,17 @@ namespace Microsoft.Extensions.Configuration
             return indexOf < 0 ? key.Substring(prefixLength) : key.Substring(prefixLength, indexOf - prefixLength);
         }
 
+        /// <summary>
+        /// Returns a <see cref="IChangeToken"/> that can be used to listen when this provider is reloaded.
+        /// </summary>
+        /// <returns></returns>
         public IChangeToken GetReloadToken()
         {
             return _reloadToken;
         }
 
         /// <summary>
-        /// Fires the Change Token
+        /// Triggers the reload change token and creates a new one.
         /// </summary>
         protected void OnReload()
         {

src/Microsoft.Extensions.Configuration/ConfigurationReloadToken.cs

@@ -7,16 +7,35 @@ using Microsoft.Extensions.Primitives;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// Implements <see cref="IChangeToken"/>
+    /// </summary>
     public class ConfigurationReloadToken : IChangeToken
     {
         private CancellationTokenSource _cts = new CancellationTokenSource();
 
+        /// <summary>
+        /// Indicates if this token will proactively raise callbacks. Callbacks are still guaranteed to be invoked, eventually.
+        /// </summary>
         public bool ActiveChangeCallbacks => true;
 
+        /// <summary>
+        /// Gets a value that indicates if a change has occured.
+        /// </summary>
         public bool HasChanged => _cts.IsCancellationRequested;
 
+        /// <summary>
+        /// Registers for a callback that will be invoked when the entry has changed. Microsoft.Extensions.Primitives.IChangeToken.HasChanged
+        /// MUST be set before the callback is invoked.
+        /// </summary>
+        /// <param name="callback">The callback to invoke.</param>
+        /// <param name="state">State to be passed into the callback.</param>
+        /// <returns></returns>
         public IDisposable RegisterChangeCallback(Action<object> callback, object state) => _cts.Token.Register(callback, state);
 
+        /// <summary>
+        /// Used to trigger the change token when a reload occurs.
+        /// </summary>
         public void OnReload() => _cts.Cancel();
     }
 }

src/Microsoft.Extensions.Configuration/ConfigurationRoot.cs

@@ -9,11 +9,18 @@ using Microsoft.Extensions.Primitives;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// The root node for a configuration.
+    /// </summary>
     public class ConfigurationRoot : IConfigurationRoot
     {
         private IList<IConfigurationProvider> _providers;
         private ConfigurationReloadToken _changeToken = new ConfigurationReloadToken();
 
+        /// <summary>
+        /// Initializes a Configuration root with a list of providers.
+        /// </summary>
+        /// <param name="providers">The <see cref="IConfigurationProvider"/>s for this configuration.</param>
         public ConfigurationRoot(IList<IConfigurationProvider> providers)
         {
             if (providers == null)
@@ -29,6 +36,11 @@ namespace Microsoft.Extensions.Configuration
             }
         }
 
+        /// <summary>
+        /// Gets or sets the value corresponding to a configuration key.
+        /// </summary>
+        /// <param name="key">The configuration key.</param>
+        /// <returns>The configuration value.</returns>
         public string this[string key]
         {
             get
@@ -60,6 +72,10 @@ namespace Microsoft.Extensions.Configuration
             }
         }
 
+        /// <summary>
+        /// Gets the immediate children sub-sections.
+        /// </summary>
+        /// <returns></returns>
         public IEnumerable<IConfigurationSection> GetChildren() => GetChildrenImplementation(null);
 
         internal IEnumerable<IConfigurationSection> GetChildrenImplementation(string path)
@@ -71,16 +87,32 @@ namespace Microsoft.Extensions.Configuration
                 .Select(key => GetSection(path == null ? key : ConfigurationPath.Combine(path, key)));
         }
 
+        /// <summary>
+        /// Returns a <see cref="IChangeToken"/> that can be used to observe when this configuration is reloaded.
+        /// </summary>
+        /// <returns></returns>
         public IChangeToken GetReloadToken()
         {
             return _changeToken;
         }
 
+        /// <summary>
+        /// Gets a configuration sub-section with the specified key.
+        /// </summary>
+        /// <param name="key">The key of the configuration section.</param>
+        /// <returns>The <see cref="IConfigurationSection"/>.</returns>
+        /// <remarks>
+        ///     This method will never return <c>null</c>. If no matching sub-section is found with the specified key,
+        ///     an empty <see cref="IConfigurationSection"/> will be returned.
+        /// </remarks>
         public IConfigurationSection GetSection(string key)
         {
             return new ConfigurationSection(this, key);
         }
 
+        /// <summary>
+        /// Force the configuration values to be reloaded from the underlying sources.
+        /// </summary>
         public void Reload()
         {
             foreach (var provider in _providers)

src/Microsoft.Extensions.Configuration/ConfigurationSection.cs

@@ -8,12 +8,20 @@ using Microsoft.Extensions.Primitives;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// Represents a section of application configuration values.
+    /// </summary>
     public class ConfigurationSection : IConfigurationSection
     {
         private readonly ConfigurationRoot _root;
         private readonly string _path;
         private string _key;
 
+        /// <summary>
+        /// Initializes a new instance.
+        /// </summary>
+        /// <param name="root">The configuration root.</param>
+        /// <param name="path">The path to this section.</param>
         public ConfigurationSection(ConfigurationRoot root, string path)
         {
             if (root == null)
@@ -30,8 +38,14 @@ namespace Microsoft.Extensions.Configuration
             _path = path;
         }
 
+        /// <summary>
+        /// Gets the full path to this section from the <see cref="IConfigurationRoot"/>.
+        /// </summary>
         public string Path => _path;
 
+        /// <summary>
+        /// Gets the key this section occupies in its parent.
+        /// </summary>
         public string Key
         {
             get
@@ -45,6 +59,9 @@ namespace Microsoft.Extensions.Configuration
             }
         }
 
+        /// <summary>
+        /// Gets or sets the section value.
+        /// </summary>
         public string Value
         {
             get
@@ -57,6 +74,11 @@ namespace Microsoft.Extensions.Configuration
             }
         }
 
+        /// <summary>
+        /// Gets or sets the value corresponding to a configuration key.
+        /// </summary>
+        /// <param name="key">The configuration key.</param>
+        /// <returns>The configuration value.</returns>
         public string this[string key]
         {
             get
@@ -70,10 +92,27 @@ namespace Microsoft.Extensions.Configuration
             }
         }
 
+        /// <summary>
+        /// Gets a configuration sub-section with the specified key.
+        /// </summary>
+        /// <param name="key">The key of the configuration section.</param>
+        /// <returns>The <see cref="IConfigurationSection"/>.</returns>
+        /// <remarks>
+        ///     This method will never return <c>null</c>. If no matching sub-section is found with the specified key,
+        ///     an empty <see cref="IConfigurationSection"/> will be returned.
+        /// </remarks>
         public IConfigurationSection GetSection(string key) => _root.GetSection(ConfigurationPath.Combine(Path, key));
 
+        /// <summary>
+        /// Gets the immediate descendant configuration sub-sections.
+        /// </summary>
+        /// <returns>The configuration sub-sections.</returns>
         public IEnumerable<IConfigurationSection> GetChildren() => _root.GetChildrenImplementation(Path);
 
+        /// <summary>
+        /// Returns a <see cref="IChangeToken"/> that can be used to observe when this configuration is reloaded.
+        /// </summary>
+        /// <returns></returns>
         public IChangeToken GetReloadToken() => _root.GetReloadToken();
     }
 }

src/Microsoft.Extensions.Configuration/MemoryConfigurationBuilderExtensions.cs

@@ -7,6 +7,9 @@ using Microsoft.Extensions.Configuration.Memory;
 
 namespace Microsoft.Extensions.Configuration
 {
+    /// <summary>
+    /// IConfigurationBuilder extension methods for the MemoryConfigurationProvider.
+    /// </summary>
     public static class MemoryConfigurationBuilderExtensions
     {
         /// <summary>

src/Microsoft.Extensions.Configuration/MemoryConfigurationProvider.cs

@@ -7,10 +7,17 @@ using System.Collections.Generic;
 
 namespace Microsoft.Extensions.Configuration.Memory
 {
+    /// <summary>
+    /// In-memory implementation of <see cref="IConfigurationProvider"/>
+    /// </summary>
     public class MemoryConfigurationProvider : ConfigurationProvider, IEnumerable<KeyValuePair<string, string>>
     {
         private readonly MemoryConfigurationSource _source;
 
+        /// <summary>
+        /// Initialize a new instance from the source.
+        /// </summary>
+        /// <param name="source">The source settings.</param>
         public MemoryConfigurationProvider(MemoryConfigurationSource source)
         {
             if (source == null)
@@ -29,16 +36,29 @@ namespace Microsoft.Extensions.Configuration.Memory
             }
         }
 
+        /// <summary>
+        /// Add a new key and value pair.
+        /// </summary>
+        /// <param name="key">The configuration key.</param>
+        /// <param name="value">The configuration value.</param>
         public void Add(string key, string value)
         {
             Data.Add(key, value);
         }
 
+        /// <summary>
+        /// Returns an enumerator that iterates through the collection.
+        /// </summary>
+        /// <returns>An enumerator that can be used to iterate through the collection.</returns>
         public IEnumerator<KeyValuePair<string, string>> GetEnumerator()
         {
             return Data.GetEnumerator();
         }
 
+        /// <summary>
+        /// Returns an enumerator that iterates through the collection.
+        /// </summary>
+        /// <returns>An enumerator that can be used to iterate through the collection.</returns>
         IEnumerator IEnumerable.GetEnumerator()
         {
             return GetEnumerator();

src/Microsoft.Extensions.Configuration/MemoryConfigurationSource.cs

@@ -1,16 +1,25 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
-using System.Collections;
 using System.Collections.Generic;
 
 namespace Microsoft.Extensions.Configuration.Memory
 {
+    /// <summary>
+    /// Represents in-memory data as an <see cref="IConfigurationSource"/>.
+    /// </summary>
     public class MemoryConfigurationSource : IConfigurationSource
     {
+        /// <summary>
+        /// The initial key value configuration pairs.
+        /// </summary>
         public IEnumerable<KeyValuePair<string, string>> InitialData { get; set; }
 
+        /// <summary>
+        /// Builds the <see cref="MemoryConfigurationProvider"/> for this source.
+        /// </summary>
+        /// <param name="builder">The <see cref="IConfigurationBuilder"/>.</param>
+        /// <returns>A <see cref="MemoryConfigurationProvider"/></returns>
         public IConfigurationProvider Build(IConfigurationBuilder builder)
         {
             return new MemoryConfigurationProvider(this);

src/Microsoft.Extensions.Configuration/project.json

@@ -3,9 +3,6 @@
   "buildOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [
-      "CS1591"
-    ],
     "xmlDoc": true
   },
   "description": "Implementation of key-value pair based configuration for Microsoft.Extensions.Configuration. Includes the memory configuration provider.",