Added Unified connection support (#3785)

* Added Unified connection support

* Use generic way to do expandNode.
Cleanup the ported code and removed unreference code. Added as needed later.
Resolved PR comments.

* Minor fixes and removed timer for all expanders for now. If any providers can't response, the tree node will spin and wait. We may improve later.

* Change handSessionClose to not thenable.
Added a node to OE to show error message instead of reject. So we could show partial expanded result if get any.
Resolve PR comments

* Minor fixes of PR comments

extensions/mssql/src/apiWrapper.ts

@@ -0,0 +1,93 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+'use strict';
+
+import * as vscode from 'vscode';
+import * as sqlops from 'sqlops';
+
+/**
+ * Wrapper class to act as a facade over VSCode and Data APIs and allow us to test / mock callbacks into
+ * this API from our code
+ *
+ * @export
+ * @class ApiWrapper
+ */
+export class ApiWrapper {
+	// Data APIs
+	public registerConnectionProvider(provider: sqlops.ConnectionProvider): vscode.Disposable {
+		return sqlops.dataprotocol.registerConnectionProvider(provider);
+	}
+
+	public registerObjectExplorerNodeProvider(provider: sqlops.ObjectExplorerNodeProvider): vscode.Disposable {
+		return sqlops.dataprotocol.registerObjectExplorerNodeProvider(provider);
+	}
+
+	public registerTaskServicesProvider(provider: sqlops.TaskServicesProvider): vscode.Disposable {
+		return sqlops.dataprotocol.registerTaskServicesProvider(provider);
+	}
+
+	public registerFileBrowserProvider(provider: sqlops.FileBrowserProvider): vscode.Disposable {
+		return sqlops.dataprotocol.registerFileBrowserProvider(provider);
+	}
+
+	public registerTaskHandler(taskId: string, handler: (profile: sqlops.IConnectionProfile) => void): void {
+		sqlops.tasks.registerTask(taskId, handler);
+	}
+
+	// VSCode APIs
+
+	public executeCommand(command: string, ...rest: any[]): Thenable<any> {
+		return vscode.commands.executeCommand(command, ...rest);
+	}
+
+	public registerCommand(command: string, callback: (...args: any[]) => any, thisArg?: any): vscode.Disposable {
+		return vscode.commands.registerCommand(command, callback, thisArg);
+	}
+
+	public showOpenDialog(options: vscode.OpenDialogOptions): Thenable<vscode.Uri[] | undefined> {
+		return vscode.window.showOpenDialog(options);
+	}
+
+	public showSaveDialog(options: vscode.SaveDialogOptions): Thenable<vscode.Uri> {
+		return vscode.window.showSaveDialog(options);
+	}
+
+	public openTextDocument(uri: vscode.Uri): Thenable<vscode.TextDocument>;
+	public openTextDocument(options: { language?: string; content?: string; }): Thenable<vscode.TextDocument>;
+	public openTextDocument(uriOrOptions): Thenable<vscode.TextDocument> {
+		return vscode.workspace.openTextDocument(uriOrOptions);
+	}
+
+	public showTextDocument(document: vscode.TextDocument, column?: vscode.ViewColumn, preserveFocus?: boolean, preview?: boolean): Thenable<vscode.TextEditor> {
+		let options: vscode.TextDocumentShowOptions = {
+			viewColumn: column,
+			preserveFocus: preserveFocus,
+			preview: preview
+		};
+		return vscode.window.showTextDocument(document, options);
+	}
+
+	public showErrorMessage(message: string, ...items: string[]): Thenable<string | undefined> {
+		return vscode.window.showErrorMessage(message, ...items);
+	}
+
+	public showWarningMessage(message: string, ...items: string[]): Thenable<string | undefined> {
+		return vscode.window.showWarningMessage(message, ...items);
+	}
+
+	public showInformationMessage(message: string, ...items: string[]): Thenable<string | undefined> {
+		return vscode.window.showInformationMessage(message, ...items);
+	}
+
+	public createStatusBarItem(alignment?: vscode.StatusBarAlignment, priority?: number): vscode.StatusBarItem {
+		return vscode.window.createStatusBarItem(alignment, priority);
+	}
+
+	public get workspaceFolders(): vscode.WorkspaceFolder[] {
+		return vscode.workspace.workspaceFolders;
+	}
+
+}