(GH-121) Refactoring of ConfigurationHandler

- Based on the work in this repository:
https://github.com/tintoy/msbuild-project-tools-server
- Needed updated due to changes in most recent version of Omnisharp

src/Chocolatey.Language.Server/.vscode/launch.json

@@ -0,0 +1,26 @@
+{
+  // Use IntelliSense to learn about possible attributes.
+  // Hover to view descriptions of existing attributes.
+  // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "name": ".NET Core Launch (console)",
+      "type": "coreclr",
+      "request": "launch",
+      "preLaunchTask": "build",
+      "program": "${workspaceFolder}/bin/Debug/netcoreapp2.1/Chocolatey.Language.Server.dll",
+      "args": [],
+      "cwd": "${workspaceFolder}",
+      "console": "internalConsole",
+      "stopAtEntry": false,
+      "internalConsoleOptions": "openOnSessionStart"
+    },
+    {
+      "name": ".NET Core Attach",
+      "type": "coreclr",
+      "request": "attach",
+      "processId": "${command:pickProcess}"
+    }
+  ]
+}

src/Chocolatey.Language.Server/.vscode/tasks.json

@@ -0,0 +1,15 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "build",
+            "command": "dotnet",
+            "type": "process",
+            "args": [
+                "build",
+                "${workspaceFolder}/Chocolatey.Language.Server.csproj"
+            ],
+            "problemMatcher": "$msCompile"
+        }
+    ]
+}

src/Chocolatey.Language.Server/Chocolatey.Language.Server.csproj

@@ -9,6 +9,10 @@
   <ItemGroup>
     <PackageReference Include="GuiLabs.Language.Xml" Version="1.2.35" />
     <PackageReference Include="OmniSharp.Extensions.LanguageServer" Version="0.11.3" />
+    <PackageReference Include="Serilog" Version="2.5.0" />
+    <PackageReference Include="Serilog.Enrichers.Demystify" Version="0.1.0-dev-00016" />
+    <PackageReference Include="Serilog.Extensions.Logging" Version="2.0.2" />
+    <PackageReference Include="Serilog.Sinks.Seq" Version="3.3.3" />
   </ItemGroup>
 
 </Project>

src/Chocolatey.Language.Server/Configuration.cs

@@ -0,0 +1,45 @@
+using System.Collections.Generic;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+
+namespace Chocolatey.Language.Server
+{
+    public sealed class Configuration
+    {
+        /// <summary>
+        ///     The name of the configuration section as passed in messages such as <see cref="CustomProtocol.DidChangeConfigurationObjectParams"/>.
+        /// </summary>
+        public static readonly string SectionName = "chocoLanguageServer";
+
+        /// <summary>
+        ///     The MSBuild language service's main configuration.
+        /// </summary>
+        [JsonProperty("language", ObjectCreationHandling = ObjectCreationHandling.Reuse)]
+        public LanguageConfiguration Language { get; } = new LanguageConfiguration();
+    }
+
+    /// <summary>
+    ///     The main settings for the MSBuild language service.
+    /// </summary>
+    public class LanguageConfiguration
+    {
+        /// <summary>
+        ///     Create a new <see cref="LanguageConfiguration"/>.
+        /// </summary>
+        public LanguageConfiguration()
+        {
+        }
+
+        /// <summary>
+        ///     Disable the language service?
+        /// </summary>
+        [JsonProperty("useClassicProvider")]
+        public bool DisableLanguageService { get; set; } = false;
+
+        /// <summary>
+        ///     Types of object from the current project to include when offering completions.
+        /// </summary>
+        [JsonProperty("suppressedRules", ObjectCreationHandling = ObjectCreationHandling.Reuse)]
+        public HashSet<string> SuppressedRules { get; } = new HashSet<string>();
+    }
+}

src/Chocolatey.Language.Server/CustomProtocol/DidChangeConfigurationSettings.cs

@@ -0,0 +1,31 @@
+using OmniSharp.Extensions.JsonRpc;
+using OmniSharp.Extensions.LanguageServer;
+using OmniSharp.Extensions.LanguageServer.Protocol;
+using OmniSharp.Extensions.LanguageServer.Protocol.Client.Capabilities;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using OmniSharp.Extensions.Embedded.MediatR;
+
+namespace Chocolatey.Language.Server.CustomProtocol
+{
+    /// <summary>
+    ///     Custom handler for "workspace/didChangeConfiguration" with the configuration as a <see cref="JObject"/>.
+    /// </summary>
+    [Method("workspace/didChangeConfiguration")]
+    public interface IDidChangeConfigurationSettingsHandler
+        : IJsonRpcNotificationHandler<DidChangeConfigurationObjectParams>, IJsonRpcHandler, IRegistration<object>, ICapability<DidChangeConfigurationCapability>
+    {
+    }
+
+    /// <summary>
+    ///     Notification parameters for "workspace/didChangeConfiguration".
+    /// </summary>
+    public class DidChangeConfigurationObjectParams : IRequest
+    {
+        /// <summary>
+        ///     The current settings.
+        /// </summary>
+        [JsonProperty("settings")]
+        public JToken Settings;
+    }
+}

src/Chocolatey.Language.Server/CustomProtocol/ProtocolExtensions.cs

@@ -0,0 +1,115 @@
+using OmniSharp.Extensions.LanguageServer;
+using OmniSharp.Extensions.LanguageServer.Protocol.Models;
+using OmniSharp.Extensions.LanguageServer.Server;
+using System;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using System.Linq;
+
+namespace Chocolatey.Language.Server.CustomProtocol
+{
+    /// <summary>
+    ///     Custom Language Server Protocol extensions.
+    /// </summary>
+    public static class ProtocolExtensions
+    {
+        /// <summary>
+        ///     Update the configuration from the specified configuration-change notification.
+        /// </summary>
+        /// <param name="configuration">
+        ///     The <see cref="Configuration"/> to update.
+        /// </param>
+        /// <param name="request">
+        ///     The configuration-change notification.
+        /// </param>
+        public static void UpdateFrom(this Configuration configuration, DidChangeConfigurationObjectParams request)
+        {
+            if (configuration == null)
+            {
+                throw new ArgumentNullException(nameof(configuration));
+            }
+
+            if (request == null)
+            {
+                throw new ArgumentNullException(nameof(request));
+            }
+
+            JObject json = request.Settings?.SelectToken(Configuration.SectionName) as JObject;
+
+            if (json == null)
+            {
+                return;
+            }
+
+            configuration.UpdateFrom(json);
+        }
+
+        /// <summary>
+        ///     Update the configuration from the specified initialisation request.
+        /// </summary>
+        /// <param name="configuration">
+        ///     The <see cref="Configuration"/> to update.
+        /// </param>
+        /// <param name="request">
+        ///     The initialisation request.
+        /// </param>
+        public static void UpdateFrom(this Configuration configuration, InitializeParams request)
+        {
+            if (configuration == null)
+            {
+                throw new ArgumentNullException(nameof(configuration));
+            }
+
+            if (request == null)
+            {
+                throw new ArgumentNullException(nameof(request));
+            }
+
+            JToken initializationParameters = request.InitializationOptions as JToken;
+
+            if (initializationParameters == null)
+            {
+                return;
+            }
+
+            JObject json = initializationParameters.SelectToken(Configuration.SectionName) as JObject;
+
+            if (json == null)
+            {
+                return;
+            }
+
+            configuration.UpdateFrom(json);
+        }
+
+        /// <summary>
+        ///     Update the configuration from the specified JSON.
+        /// </summary>
+        /// <param name="configuration">
+        ///     The <see cref="Configuration"/> to update.
+        /// </param>
+        /// <param name="settingsJson">
+        ///     A <see cref="JObject"/> representing the flattened settings JSON from VS Code.
+        /// </param>
+        public static void UpdateFrom(this Configuration configuration, JObject settingsJson)
+        {
+            if (configuration == null)
+            {
+                throw new ArgumentNullException(nameof(configuration));
+            }
+
+            if (settingsJson == null)
+            {
+                throw new ArgumentNullException(nameof(settingsJson));
+            }
+
+            // Temporary workaround - JsonSerializer.Populate reuses existing HashSet.
+            configuration.Language.SuppressedRules.Clear();
+
+            using (JsonReader reader = settingsJson.CreateReader())
+            {
+                new JsonSerializer().Populate(reader, configuration);
+            }
+        }
+    }
+}