Add server->client notification to show toast and implement for project

load failures

src/Features/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/HostWorkspace/LanguageServerProjectSystem.cs

@@ -7,11 +7,10 @@
 using System.Composition;
 using System.Diagnostics;
 using System.Runtime.CompilerServices;
+using System.Threading;
 using Microsoft.Build.Locator;
 using Microsoft.CodeAnalysis.Collections;
 using Microsoft.CodeAnalysis.Host.Mef;
-using Microsoft.CodeAnalysis.LanguageServer.Handler.DebugConfiguration;
-using Microsoft.CodeAnalysis.LanguageServer.LanguageServer;
 using Microsoft.CodeAnalysis.MSBuild;
 using Microsoft.CodeAnalysis.MSBuild.Build;
 using Microsoft.CodeAnalysis.MSBuild.Logging;
@@ -20,7 +19,9 @@
 using Microsoft.CodeAnalysis.Workspaces.ProjectSystem;
 using Microsoft.Extensions.Logging;
 using Microsoft.VisualStudio.Composition;
+using Microsoft.VisualStudio.TestPlatform.CommunicationUtilities;
 using Roslyn.Utilities;
+using LSP = Microsoft.VisualStudio.LanguageServer.Protocol;
 
 namespace Microsoft.CodeAnalysis.LanguageServer.HostWorkspace;
 
@@ -76,7 +77,13 @@ public LanguageServerProjectSystem(
 
     public async Task OpenSolutionAsync(string solutionFilePath)
     {
-        await TryEnsureMSBuildLoadedAsync(Path.GetDirectoryName(solutionFilePath)!);
+        var result = await TryEnsureMSBuildLoadedAsync(Path.GetDirectoryName(solutionFilePath)!);
+        if (!result)
+        {
+            var message = string.Format(LanguageServerResources.There_were_errors_loading_solution_0_See_log_for_details, Path.GetFileName(solutionFilePath));
+            await ShowToastNotification.ShowToastNotificationAsync(LSP.MessageType.Error, message, CancellationToken.None, ShowToastNotification.ShowCSharpLogsCommand);
+        }
+
         await OpenSolutionCoreAsync(solutionFilePath);
     }
 
@@ -207,7 +214,26 @@ private async Task LoadOrReloadProjectAsync(string projectPath, ProjectBuildMana
                 {
                     foreach (var logItem in loadedFile.Log)
                     {
-                        _logger.LogWarning($"{logItem.Kind} while loading {logItem.ProjectFilePath}: {logItem.Message}");
+                        var projectName = Path.GetFileName(projectPath);
+                        var messageType = logItem.Kind switch
+                        {
+                            WorkspaceDiagnosticKind.Failure => LSP.MessageType.Error,
+                            WorkspaceDiagnosticKind.Warning => LSP.MessageType.Warning,
+                            _ => throw ExceptionUtilities.UnexpectedValue(logItem.Kind)
+                        };
+
+                        if (messageType is LSP.MessageType.Error)
+                        {
+                            _logger.LogError($"{logItem.Kind} while loading {logItem.ProjectFilePath}: {logItem.Message}");
+                            var message = string.Format(LanguageServerResources.There_were_errors_loading_project_0_See_log_for_details, projectName);
+                            await ShowToastNotification.ShowToastNotificationAsync(messageType, message, cancellationToken, ShowToastNotification.ShowCSharpLogsCommand);
+                        }
+                        else
+                        {
+                            _logger.LogWarning($"{logItem.Kind} while loading {logItem.ProjectFilePath}: {logItem.Message}");
+                            var message = string.Format(LanguageServerResources.There_were_warnings_loading_project_0_See_log_for_details, projectName);
+                            await ShowToastNotification.ShowToastNotificationAsync(messageType, message, cancellationToken, ShowToastNotification.ShowCSharpLogsCommand);
+                        }
                     }
                 }
                 else
@@ -219,6 +245,8 @@ private async Task LoadOrReloadProjectAsync(string projectPath, ProjectBuildMana
         catch (Exception e)
         {
             _logger.LogError(e, $"Exception thrown while loading {projectPath}");
+            var message = string.Format(LanguageServerResources.There_were_errors_loading_project_0_See_log_for_details, Path.GetFileName(projectPath));
+            await ShowToastNotification.ShowToastNotificationAsync(LSP.MessageType.Error, message, cancellationToken, ShowToastNotification.ShowCSharpLogsCommand);
         }
     }
 }

src/Features/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/LanguageServerResources.resx

@@ -162,6 +162,9 @@
   <data name="Running_tests" xml:space="preserve">
     <value>Running tests...</value>
   </data>
+  <data name="Show_csharp_logs" xml:space="preserve">
+    <value>Show C# logs</value>
+  </data>
   <data name="Stack_Trace" xml:space="preserve">
     <value>Stack Trace</value>
   </data>
@@ -180,4 +183,13 @@
   <data name="Test_run_error" xml:space="preserve">
     <value>Test run error: {0}</value>
   </data>
+  <data name="There_were_errors_loading_project_0_See_log_for_details" xml:space="preserve">
+    <value>There were errors loading project {0}. See log for details.</value>
+  </data>
+  <data name="There_were_errors_loading_solution_0_See_log_for_details" xml:space="preserve">
+    <value>There were errors loading solutution {0}. See log for details.</value>
+  </data>
+  <data name="There_were_warnings_loading_project_0_See_log_for_details" xml:space="preserve">
+    <value>There were warnings loading project {0}. See log for details.</value>
+  </data>
 </root>

src/Features/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/Logging/ShowToastNotification.cs

@@ -0,0 +1,41 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.Serialization;
+using Microsoft.CodeAnalysis.LanguageServer.LanguageServer;
+using Roslyn.Utilities;
+using LSP = Microsoft.VisualStudio.LanguageServer.Protocol;
+
+namespace Microsoft.CodeAnalysis.LanguageServer;
+
+/// <summary>
+/// Implements a custom version of the standard 'window/showMessageRequest' to display a toast on the client.
+/// The standard version requires us to wait for a response and then do something on the server with it.
+/// That can be useful in certain cases, but a lot of the time we just want to show a toast with buttons that map to client side commands.
+/// This request allows us to do just that.
+/// </summary>
+internal class ShowToastNotification
+{
+    private const string ShowToastNotificationName = "window/showToast";
+
+    public static readonly LSP.Command ShowCSharpLogsCommand = new()
+    {
+        Title = LanguageServerResources.Show_csharp_logs,
+        CommandIdentifier = "csharp.showOutputWindow"
+    };
+
+    public static async Task ShowToastNotificationAsync(LSP.MessageType messageType, string message, CancellationToken cancellationToken, params LSP.Command[] commands)
+    {
+        Contract.ThrowIfNull(LanguageServerHost.Instance, "We don't have an LSP channel yet to send this request through.");
+        var languageServerManager = LanguageServerHost.Instance.GetRequiredLspService<IClientLanguageServerManager>();
+        var toastParams = new ShowToastNotificationParams(messageType, message, commands);
+        await languageServerManager.SendNotificationAsync(ShowToastNotificationName, toastParams, cancellationToken);
+    }
+
+    [DataContract]
+    private record ShowToastNotificationParams(
+        [property: DataMember(Name = "messageType")] LSP.MessageType MessageType,
+        [property: DataMember(Name = "message")] string Message,
+        [property: DataMember(Name = "commands")] LSP.Command[] Commands);
+}