Add better error message when cadl-server is not found in Visual Studio

common/changes/cadl-vs/fix-vs-cadl-server-not-found_2022-06-07-21-16.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "cadl-vs",
+      "comment": "Improve error reporting when cadl-server is not found",
+      "type": "patch"
+    }
+  ],
+  "packageName": "cadl-vs"
+}

common/changes/cadl-vscode/fix-vs-cadl-server-not-found_2022-06-07-21-16.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "cadl-vscode",
+      "comment": "Improve error reporting when cadl-server is not found",
+      "type": "patch"
+    }
+  ],
+  "packageName": "cadl-vscode"
+}

packages/cadl-vs/src/Exceptions.cs

@@ -0,0 +1,42 @@
+using System;
+
+namespace Microsoft.Cadl.VisualStudio;
+
+/// <summary>
+/// Provide a typed map for Win32 error codes as described here https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/18d8fbe8-a967-4f1c-ae50-99ca8e491d2d
+/// </summary>
+internal class Win32ErrorCodes
+{
+    public const int ERROR_FILE_NOT_FOUND = 2;
+}
+
+
+[Serializable]
+public class CadlUserErrorException : Exception
+{
+    public CadlUserErrorException() { }
+
+    public CadlUserErrorException(string message)
+        : base(message)
+    {
+
+    }
+}
+
+
+[Serializable]
+public class CadlServerNotFound : CadlUserErrorException
+{
+    public CadlServerNotFound() { }
+
+    public CadlServerNotFound(string name)
+        : base(string.Join("\n", new string[]
+        {
+            $"Cadl server exectuable was not found: '{name}' is not found. Make sure either:",
+            " - cadl is installed globally with `npm install -g @cadl-lang/compiler'.",
+            " - cadl server path is configured with https://github.com/microsoft/cadl/blob/main/packages/cadl-vs/README.md#configure-cadl-visual-studio-extension."
+        }))
+    {
+
+    }
+}

packages/cadl-vs/src/VSExtension.cs

@@ -16,6 +16,7 @@
 using Microsoft.VisualStudio.Utilities;
 using Task = System.Threading.Tasks.Task;
 using System.Linq;
+using System.ComponentModel;
 
 namespace Microsoft.Cadl.VisualStudio
 {
@@ -82,20 +83,32 @@ public LanguageClient([Import] IVsFolderWorkspaceService workspaceService)
             };
 
 #if DEBUG
-      // Use local build of cadl-server in development (lauched from F5 in VS)
-      if (InDevelopmentMode()) {
-        // --nolazy isn't supported by NODE_OPTIONS so we pass these via CLI instead
-        info.Environment.Remove("NODE_OPTIONS");
-      }
+            // Use local build of cadl-server in development (lauched from F5 in VS)
+            if (InDevelopmentMode())
+            {
+                // --nolazy isn't supported by NODE_OPTIONS so we pass these via CLI instead
+                info.Environment.Remove("NODE_OPTIONS");
+            }
 #endif
+            try
+            {
+                var process = Process.Start(info);
+                process.BeginErrorReadLine();
+                process.ErrorDataReceived += (_, e) => LogStderrMessage(e.Data);
 
-            var process = Process.Start(info);
-            process.BeginErrorReadLine();
-            process.ErrorDataReceived += (_, e) => LogStderrMessage(e.Data);
+                return new Connection(
+                  process.StandardOutput.BaseStream,
+                  process.StandardInput.BaseStream);
+            }
+            catch (Win32Exception e)
+            {
+                if (e.NativeErrorCode == Win32ErrorCodes.ERROR_FILE_NOT_FOUND)
+                {
+                    throw new CadlServerNotFound(info.FileName);
+                }
+                throw e;
+            }
 
-            return new Connection(
-              process.StandardOutput.BaseStream,
-              process.StandardInput.BaseStream);
         }
 
         public async Task OnLoadedAsync()
@@ -108,21 +121,24 @@ public async Task OnLoadedAsync()
         }
 
 #if VS2019
-    public Task OnServerInitializeFailedAsync(Exception e) {
-      Debug.Fail("Failed to initialize cadl-server:\r\n\r\n" + e);
-      return Task.CompletedTask;
-    }
+        public Task OnServerInitializeFailedAsync(Exception e)
+        {
+            var message = e is CadlUserErrorException ? e.Message : e.ToString();
+            Debug.Fail("Failed to initialize cadl-server:\r\n\r\n" + message);
+            return Task.CompletedTask;
+        }
 #endif
 
 #if VS2022
     public Task<InitializationFailureContext?> OnServerInitializeFailedAsync(ILanguageClientInitializationInfo initializationState) {
       var exception = initializationState.InitializationException;
+      var message = exception is CadlUserErrorException 
+        ? exception.Message 
+        : $"File issue at https://github.com/microsoft/cadl\r\n\r\n{exception?.ToString()}";
       Debug.Fail("Failed to initialize cadl-server:\r\n\r\n" + exception);
       return Task.FromResult<InitializationFailureContext?>(
         new InitializationFailureContext {
-          FailureMessage = "Failed to activate Cadl language server!\r\n" +
-                           "File issue at https://github.com/microsoft/cadl\r\n\r\n" +
-                           exception
+          FailureMessage = "Failed to activate Cadl language server!\r\n" + message
       });
     }
 #endif
@@ -143,35 +159,37 @@ private void LogStderrMessage(string? message)
         }
 
 #if DEBUG
-    private static bool InDevelopmentMode() {
-      return string.Equals(
-        Environment.GetEnvironmentVariable("CADL_DEVELOPMENT_MODE"),
-        "true",
-        StringComparison.OrdinalIgnoreCase);
-    }
+        private static bool InDevelopmentMode()
+        {
+            return string.Equals(
+              Environment.GetEnvironmentVariable("CADL_DEVELOPMENT_MODE"),
+              "true",
+              StringComparison.OrdinalIgnoreCase);
+        }
 
-    private static string GetDevelopmentCadlServerPath() {
-      // Even when debugging, we get deployed to an extension folder outside the
-      // source tree, so we stash the source directory in a file in debug builds
-      // so we can use it to run cadl-server against the live developer build in
-      // the source tree.
-      var thisDir = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
-      var srcDir = File.ReadAllText(Path.Combine(thisDir, "DebugSourceDirectory.txt")).Trim();
-      return Path.GetFullPath(Path.Combine(srcDir, "../compiler/cmd/cadl-server.js"));
-    }
+        private static string GetDevelopmentCadlServerPath()
+        {
+            // Even when debugging, we get deployed to an extension folder outside the
+            // source tree, so we stash the source directory in a file in debug builds
+            // so we can use it to run cadl-server against the live developer build in
+            // the source tree.
+            var thisDir = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
+            var srcDir = File.ReadAllText(Path.Combine(thisDir, "DebugSourceDirectory.txt")).Trim();
+            return Path.GetFullPath(Path.Combine(srcDir, "../compiler/cmd/cadl-server.js"));
+        }
 #endif
 
         private (string, string[]) resolveCadlServer(IWorkspaceSettings? settings)
         {
             var args = new string[] { "--stdio" };
-
 #if DEBUG
-      // Use local build of cadl-server in development (lauched from F5 in VS)
-      if (InDevelopmentMode()) {
-        var options = Environment.GetEnvironmentVariable("CADL_SERVER_NODE_OPTIONS");
-        var module = GetDevelopmentCadlServerPath();
-        return ("node.exe", new string[] { module, options }.Concat(args).ToArray());
-      }
+            // Use local build of cadl-server in development (lauched from F5 in VS)
+            if (InDevelopmentMode())
+            {
+                var options = Environment.GetEnvironmentVariable("CADL_SERVER_NODE_OPTIONS");
+                var module = GetDevelopmentCadlServerPath();
+                return ("node.exe", new string[] { module, options }.Concat(args).ToArray());
+            }
 #endif
 
             var serverPath = settings?.Property<string>("cadl.cadl-server.path");

packages/cadl-vscode/package.json

@@ -124,7 +124,7 @@
     "tmlanguage-generator": "~0.3.0",
     "typescript": "~4.7.2",
     "vsce": "~2.6.7",
-    "vscode-languageclient": "~7.0.0",
+    "vscode-languageclient": "~8.0.0",
     "vscode-oniguruma": "~1.6.1",
     "vscode-textmate": "~6.0.0"
   }

packages/cadl-vscode/src/extension.ts

@@ -1,6 +1,6 @@
 import { stat } from "fs/promises";
 import { join } from "path";
-import { commands, ExtensionContext, workspace } from "vscode";
+import vscode, { commands, ExtensionContext, workspace } from "vscode";
 import {
   Executable,
   ExecutableOptions,
@@ -11,9 +11,30 @@ import {
 let client: LanguageClient | undefined;
 
 export async function activate(context: ExtensionContext) {
+  context.subscriptions.push(commands.registerCommand("cadl.restartServer", restartCadlServer));
+
+  return await vscode.window.withProgress(
+    {
+      title: "Launching Cadl language service...",
+      location: vscode.ProgressLocation.Notification,
+    },
+    async () => launchLanguageClient(context)
+  );
+}
+
+async function restartCadlServer(): Promise<void> {
+  if (client) {
+    await client.stop();
+    client.start();
+  }
+}
+
+async function launchLanguageClient(context: ExtensionContext) {
   const exe = await resolveCadlServer(context);
   const options: LanguageClientOptions = {
     synchronize: {
+      // Synchronize the setting section 'cadl' to the server
+      configurationSection: "cadl",
       fileEvents: [
         workspace.createFileSystemWatcher("**/*.cadl"),
         workspace.createFileSystemWatcher("**/cadl-project.yaml"),
@@ -26,24 +47,33 @@ export async function activate(context: ExtensionContext) {
     ],
   };
 
-  context.subscriptions.push(commands.registerCommand("cadl.restartServer", restartCadlServer));
-
   const name = "Cadl";
   const id = "cadlLanguageServer";
-  client = new LanguageClient(id, name, { run: exe, debug: exe }, options);
-  client.start();
-}
-
-async function restartCadlServer(): Promise<void> {
-  if (client) {
-    await client.stop();
-    client.start();
+  try {
+    client = new LanguageClient(id, name, { run: exe, debug: exe }, options);
+    await client.start();
+  } catch (e) {
+    if (typeof e === "string" && e.startsWith("Launching server using command")) {
+      client?.error(
+        [
+          `Cadl server exectuable was not found: '${exe.command}' is not found. Make sure either:`,
+          " - cadl is installed globally with `npm install -g @cadl-lang/compiler'.",
+          " - cadl server path is configured with https://github.com/microsoft/cadl#installing-vs-code-extension.",
+        ].join("\n"),
+        undefined,
+        false
+      );
+      throw `Cadl server exectuable was not found: '${exe.command}' is not found.`;
+    } else {
+      throw e;
+    }
   }
 }
 
 async function resolveCadlServer(context: ExtensionContext): Promise<Executable> {
   const nodeOptions = process.env.CADL_SERVER_NODE_OPTIONS;
   const args = ["--stdio"];
+
   // In development mode (F5 launch from source), resolve to locally built server.js.
   if (process.env.CADL_DEVELOPMENT_MODE) {
     const script = context.asAbsolutePath("../compiler/dist/server/server.js");