Support 'xml/executeClientCommand' request. Command 'xml.workspace.executeCommand'

Author: BoykoAlex

docs/Extensions.md

@@ -39,4 +39,10 @@ You can see the [vscode-xml-maven](https://github.com/angelozerr/vscode-xml-mave
 
 ## XML extension API (TypeScript)
 
-See [PR 292](https://github.com/redhat-developer/vscode-xml/pull/292)
+See [PR 292](https://github.com/redhat-developer/vscode-xml/pull/292)
+
+### Commands
+
+`xml.workspace.executeCommand` - command registered on VSCode client (via **vscode-xml** extension) to let other extensions execute commands on XML Language server
+
+`xml/executeClientCommand` - XML Language server LSP extension to let XML LS extenders execute commands on the client. The command is made available via `IXMLCommandService` on the server side. See [XML LS extensions docs](https://github.com/eclipse/lemminx/blob/master/docs/LemMinX-Extensions.md#xml-language-server-services-available-for-extensions)

src/commands.ts

@@ -50,4 +50,9 @@ export namespace Commands {
     export const OPEN_DOCS = "xml.open.docs";
 
     export const OPEN_DOCS_HOME = "xml.open.docs.home";
+    
+    /**
+     * VSCode client command to executes an LSP command on the XML Language Server
+     */
+    export const EXECUTE_WORKSPACE_COMMAND = "xml.workspace.executeCommand";
 }

src/extension.ts

@@ -11,7 +11,22 @@
  */
 
 import { prepareExecutable } from './javaServerStarter';
-import { LanguageClientOptions, RevealOutputChannelOn, LanguageClient, DidChangeConfigurationNotification, RequestType, TextDocumentPositionParams, ReferencesRequest, NotificationType, MessageType, ConfigurationRequest, ConfigurationParams } from 'vscode-languageclient';
+import { 
+  LanguageClientOptions,
+  RevealOutputChannelOn,
+  LanguageClient,
+  DidChangeConfigurationNotification,
+  RequestType,
+  TextDocumentPositionParams,
+  ReferencesRequest,
+  NotificationType,
+  MessageType,
+  ConfigurationRequest,
+  ConfigurationParams,
+  ExecuteCommandParams,
+  CancellationToken,
+  ExecuteCommandRequest
+} from 'vscode-languageclient';
 import * as requirements from './requirements';
 import { languages, IndentAction, workspace, window, commands, ExtensionContext, TextDocument, Position, LanguageConfiguration, Uri, extensions, Command, TextEditor } from "vscode";
 import * as path from 'path';
@@ -114,6 +129,10 @@ export interface XMLExtensionApi {
 
 }
 
+namespace ExecuteClientCommandRequest {
+  export const type: RequestType<ExecuteCommandParams, any, void, void> = new RequestType('xml/executeClientCommand')
+}
+
 namespace TagCloseRequest {
   export const type: RequestType<TextDocumentPositionParams, AutoCloseResult, any, any> = new RequestType('xml/closeTag');
 }
@@ -240,6 +259,30 @@ export function activate(context: ExtensionContext) {
 
       setupActionableNotificationListener(languageClient);
 
+      // Handler for 'xml/executeClientCommand` request message that executes a command on the client
+      languageClient.onRequest(ExecuteClientCommandRequest.type, async (params: ExecuteCommandParams) => {
+        return await commands.executeCommand(params.command, ...params.arguments);
+      });    
+
+      // Register client command to execute custom XML Language Server command
+      context.subscriptions.push(commands.registerCommand(Commands.EXECUTE_WORKSPACE_COMMAND, (command, ...rest) => {
+				let token: CancellationToken;
+				let commandArgs: any[] = rest;
+				if (rest && rest.length && CancellationToken.is(rest[rest.length - 1])) {
+					token = rest[rest.length - 1];
+					commandArgs = rest.slice(0, rest.length - 1);
+				}
+				const params: ExecuteCommandParams = {
+					command,
+					arguments: commandArgs
+				};
+				if (token) {
+					return languageClient.sendRequest(ExecuteCommandRequest.type, params, token);
+				} else {
+					return languageClient.sendRequest(ExecuteCommandRequest.type, params);
+				}
+      }));
+
       context.subscriptions.push(commands.registerCommand(Commands.OPEN_SETTINGS, async (settingId?: string) => {
         commands.executeCommand('workbench.action.openSettings', settingId);
       }));