Support clearing pooled connections (#2214)

src/Microsoft.SqlTools.ServiceLayer/Connection/ConnectionService.cs

@@ -1128,6 +1128,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
             serviceHost.SetRequestHandler(ChangeDatabaseRequest.Type, HandleChangeDatabaseRequest, true);
             serviceHost.SetRequestHandler(GetConnectionStringRequest.Type, HandleGetConnectionStringRequest, true);
             serviceHost.SetRequestHandler(BuildConnectionInfoRequest.Type, HandleBuildConnectionInfoRequest, true);
+            serviceHost.SetRequestHandler(ClearPooledConnectionsRequest.Type, HandleClearPooledConnectionsRequest, true);
             serviceHost.SetEventHandler(EncryptionKeysChangedNotification.Type, HandleEncryptionKeysNotificationEvent, false);
         }
 
@@ -1689,6 +1690,24 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
             }
         }
 
+        /// <summary>
+        /// Clears all pooled connections from SqlConnection pool, releasing open connection sockets not actively in use.
+        /// </summary>
+        /// <param name="_">Request param</param>
+        /// <param name="requestContext">Request Context</param>
+        /// <returns></returns>
+        public async Task HandleClearPooledConnectionsRequest(object _, RequestContext<bool> requestContext)
+        {
+            // Run a detached task to clear pools in backend.
+            await Task.Factory.StartNew(() => Task.Run(async () => {
+
+                SqlConnection.ClearAllPools();
+
+                Logger.Verbose("Cleared all pooled connections successfully.");
+                await requestContext.SendResult(true);
+            }));
+        }
+
         public ConnectionDetails ParseConnectionString(string connectionString)
         {
             SqlConnectionStringBuilder builder = new SqlConnectionStringBuilder(connectionString);

src/Microsoft.SqlTools.ServiceLayer/Connection/Contracts/ClearPooledConnectionsRequest.cs

@@ -0,0 +1,18 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using Microsoft.SqlTools.Hosting.Protocol.Contracts;
+
+namespace Microsoft.SqlTools.ServiceLayer.Connection.Contracts
+{
+    /// <summary>
+    /// Clear Pooled connectins request
+    /// </summary>
+    public class ClearPooledConnectionsRequest
+    {
+        public static readonly
+            RequestType<object, bool> Type = RequestType<object, bool>.Create("connection/clearpooledconnections");
+    }
+}