Merge from vscode 31e03b8ffbb218a87e3941f2b63a249f061fe0e4 (#4986)

src/vs/workbench/api/common/extHostStorage.ts

@@ -0,0 +1,37 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { MainContext, MainThreadStorageShape, IMainContext, ExtHostStorageShape } from './extHost.protocol';
+import { Emitter } from 'vs/base/common/event';
+
+export interface IStorageChangeEvent {
+	shared: boolean;
+	key: string;
+	value: object;
+}
+
+export class ExtHostStorage implements ExtHostStorageShape {
+
+	private _proxy: MainThreadStorageShape;
+
+	private _onDidChangeStorage = new Emitter<IStorageChangeEvent>();
+	readonly onDidChangeStorage = this._onDidChangeStorage.event;
+
+	constructor(mainContext: IMainContext) {
+		this._proxy = mainContext.getProxy(MainContext.MainThreadStorage);
+	}
+
+	getValue<T>(shared: boolean, key: string, defaultValue?: T): Promise<T | undefined> {
+		return this._proxy.$getValue<T>(shared, key).then(value => value || defaultValue);
+	}
+
+	setValue(shared: boolean, key: string, value: object): Promise<void> {
+		return this._proxy.$setValue(shared, key, value);
+	}
+
+	$acceptValue(shared: boolean, key: string, value: object): void {
+		this._onDidChangeStorage.fire({ shared, key, value });
+	}
+}