Move unused forked code to external directory (#1192)

* Move unused forked code to external directory

* Fix SLN build errors

* Add back resource provider core since it's referenced by main resource provider project

* Update PackageProjects step of pipeline

external/Microsoft.SqlTools.Hosting.v2/Channels/ChannelBase.cs

@@ -0,0 +1,58 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System.Threading.Tasks;
+using Microsoft.SqlTools.Hosting.Protocol;
+
+namespace Microsoft.SqlTools.Hosting.Channels
+{
+    /// <summary>
+    /// Defines a base implementation for servers and their clients over a
+    /// single kind of communication channel.
+    /// </summary>
+    public abstract class ChannelBase
+    {
+        #region Properties 
+        
+        /// <summary>
+        /// Gets a boolean that is true if the channel is connected or false if not.
+        /// </summary>
+        public bool IsConnected { get; protected internal set; }
+
+        /// <summary>
+        /// Gets the MessageReader for reading messages from the channel.
+        /// </summary>
+        public MessageReader MessageReader { get; protected internal set; }
+
+        /// <summary>
+        /// Gets the MessageWriter for writing messages to the channel.
+        /// </summary>
+        public MessageWriter MessageWriter { get; protected internal set; }
+        
+        #endregion
+        
+        #region Abstract Methods
+
+        /// <summary>
+        /// Starts the channel and initializes the MessageDispatcher.
+        /// </summary>
+        public abstract void Start();
+
+        /// <summary>
+        /// Stops the channel.
+        /// </summary>
+        public abstract void Stop();
+        
+        /// <summary>
+        /// Returns a Task that allows the consumer of the ChannelBase
+        /// implementation to wait until a connection has been made to
+        /// the opposite endpoint whether it's a client or server.
+        /// </summary>
+        /// <returns>A Task to be awaited until a connection is made.</returns>
+        public abstract Task WaitForConnection();
+        
+        #endregion
+    }
+}

external/Microsoft.SqlTools.Hosting.v2/Channels/StdioClientChannel.cs

@@ -0,0 +1,111 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System.Diagnostics;
+using System.IO;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.SqlTools.Hosting.Protocol;
+
+namespace Microsoft.SqlTools.Hosting.Channels
+{
+    /// <summary>
+    /// Provides a client implementation for the standard I/O channel.
+    /// Launches the server process and then attaches to its console
+    /// streams.
+    /// </summary>
+    public class StdioClientChannel : ChannelBase
+    {
+        private readonly string serviceProcessPath;
+        private readonly string serviceProcessArguments;
+
+        private Stream inputStream;
+        private Stream outputStream;
+        private Process serviceProcess;
+
+        /// <summary>
+        /// Initializes an instance of the StdioClient.
+        /// </summary>
+        /// <param name="serverProcessPath">The full path to the server process executable.</param>
+        /// <param name="serverProcessArguments">Optional arguments to pass to the service process executable.</param>
+        public StdioClientChannel(string serverProcessPath, params string[] serverProcessArguments)
+        {
+            serviceProcessPath = serverProcessPath;
+
+            if (serverProcessArguments != null)
+            {
+                serviceProcessArguments = string.Join(" ", serverProcessArguments);
+            }
+        }
+
+        public int ProcessId { get; private set; }
+        
+        public override void Start()
+        {
+            serviceProcess = new Process
+            {
+                StartInfo = new ProcessStartInfo
+                {
+                    FileName = serviceProcessPath,
+                    Arguments = serviceProcessArguments,
+                    CreateNoWindow = true,
+                    UseShellExecute = false,
+                    RedirectStandardInput = true,
+                    RedirectStandardOutput = true,
+                    RedirectStandardError = true,
+                    StandardOutputEncoding = Encoding.UTF8
+                },
+                EnableRaisingEvents = true
+            };
+
+            // Start the process
+            serviceProcess.Start();
+            ProcessId = serviceProcess.Id;
+
+            // Open the standard input/output streams
+            inputStream = serviceProcess.StandardOutput.BaseStream;
+            outputStream = serviceProcess.StandardInput.BaseStream;
+
+            // Set up the message reader and writer
+            MessageReader = new MessageReader(inputStream);
+            MessageWriter = new MessageWriter(outputStream);
+
+            IsConnected = true;
+        }
+
+        public override Task WaitForConnection()
+        {
+            // We're always connected immediately in the stdio channel
+            return Task.FromResult(true);
+        }
+
+        public override void Stop()
+        {
+            if (inputStream != null)
+            {
+                inputStream.Dispose();
+                inputStream = null;
+            }
+
+            if (outputStream != null)
+            {
+                outputStream.Dispose();
+                outputStream = null;
+            }
+
+            if (MessageReader != null)
+            {
+                MessageReader = null;
+            }
+
+            if (MessageWriter != null)
+            {
+                MessageWriter = null;
+            }
+
+            serviceProcess.Kill();
+        }
+    }
+}

external/Microsoft.SqlTools.Hosting.v2/Channels/StdioServerChannel.cs

@@ -0,0 +1,54 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System.IO;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.SqlTools.Hosting.Protocol;
+
+namespace Microsoft.SqlTools.Hosting.Channels
+{
+    /// <summary>
+    /// Provides a server implementation for the standard I/O channel.
+    /// When started in a process, attaches to the console I/O streams
+    /// to communicate with the client that launched the process.
+    /// </summary>
+    public class StdioServerChannel : ChannelBase
+    {
+        private Stream inputStream;
+        private Stream outputStream;
+
+        public override void Start()
+        {
+#if !NanoServer
+            // Ensure that the console is using UTF-8 encoding
+            System.Console.InputEncoding = Encoding.UTF8;
+            System.Console.OutputEncoding = Encoding.UTF8;
+#endif
+
+            // Open the standard input/output streams
+            inputStream = System.Console.OpenStandardInput();
+            outputStream = System.Console.OpenStandardOutput();
+
+            // Set up the reader and writer
+            MessageReader = new MessageReader(inputStream);
+            MessageWriter = new MessageWriter(outputStream);
+
+            IsConnected = true;
+        }
+
+        public override void Stop()
+        {
+            // No default implementation needed, streams will be
+            // disposed on process shutdown.
+        }
+        
+        public override Task WaitForConnection()
+        {
+            // We're always connected immediately in the stdio channel
+            return Task.FromResult(true);
+        }
+    }
+}