User data sync: Implement starting flow

- user identity
- user login provider
- user data provider
- activation event
- status bar UI

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

@@ -0,0 +1,113 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { localize } from 'vs/nls';
+import { IJSONSchema } from 'vs/base/common/jsonSchema';
+import { ExtensionMessageCollector, ExtensionsRegistry, IExtensionPoint, IExtensionPointUser } from 'vs/workbench/services/extensions/common/extensionsRegistry';
+import { IWorkbenchContributionsRegistry, Extensions as WorkbenchExtensions, IWorkbenchContribution } from 'vs/workbench/common/contributions';
+import { LifecyclePhase } from 'vs/platform/lifecycle/common/lifecycle';
+import { Registry } from 'vs/platform/registry/common/platform';
+import { IUserIdentityService, IUserIdentity } from 'vs/workbench/services/userData/common/userData';
+
+export interface IUserFriendlyUserIdentityDescriptor {
+	id: string;
+	title: string;
+	iconText: string;
+}
+
+export const userIdentityContribution: IJSONSchema = {
+	description: localize('vscode.extension.contributes.userIdentity', 'Contributes user identity to the editor'),
+	type: 'object',
+	properties: {
+		id: {
+			description: localize({ key: 'vscode.extension.contributes.user.identity.id', comment: ['Contribution refers to those that an extension contributes to VS Code through an extension/contribution point. '] }, "Unique id to identify the user user identity"),
+			type: 'string',
+			pattern: '^[a-zA-Z0-9_-]+$'
+		},
+		title: {
+			description: localize('vscode.extension.contributes.views.containers.title', 'Human readable string used to render the user identity'),
+			type: 'string'
+		},
+		iconText: {
+			description: localize('vscode.extension.contributes.views.containers.icon', "Path to the user identity icon."),
+			type: 'string'
+		}
+	}
+};
+
+
+const viewsContainersExtensionPoint: IExtensionPoint<IUserFriendlyUserIdentityDescriptor> = ExtensionsRegistry.registerExtensionPoint<IUserFriendlyUserIdentityDescriptor>({
+	extensionPoint: 'userIdentity',
+	jsonSchema: userIdentityContribution
+});
+
+class UserIdentityExtensionHandler implements IWorkbenchContribution {
+
+	constructor(
+		@IUserIdentityService private readonly userIdentityService: IUserIdentityService
+	) {
+		this.handleAndRegisterUserIdentities();
+	}
+
+	private handleAndRegisterUserIdentities() {
+		viewsContainersExtensionPoint.setHandler((extensions, { added, removed }) => {
+			if (removed.length) {
+				this.removeUserIdentities(removed);
+			}
+			if (added.length) {
+				this.addUserIdentities(added);
+			}
+		});
+	}
+
+	private addUserIdentities(extensionPoints: readonly IExtensionPointUser<IUserFriendlyUserIdentityDescriptor>[]) {
+		const userIdentities: IUserIdentity[] = [];
+		for (let { value, collector } of extensionPoints) {
+			if (!this.isValidUserIdentity(value, collector)) {
+				return;
+			}
+			userIdentities.push({
+				identity: value.id,
+				title: value.title,
+				iconText: `$(${value.iconText})`
+			});
+		}
+		if (userIdentities.length) {
+			this.userIdentityService.registerUserIdentities(userIdentities);
+		}
+	}
+
+	private removeUserIdentities(extensionPoints: readonly IExtensionPointUser<IUserFriendlyUserIdentityDescriptor>[]) {
+		const identities = extensionPoints.map(({ value }) => value.id);
+		if (identities.length) {
+			this.userIdentityService.deregisterUserIdentities(identities);
+		}
+	}
+
+
+	private isValidUserIdentity(userIdentityDescriptor: IUserFriendlyUserIdentityDescriptor, collector: ExtensionMessageCollector): boolean {
+		if (typeof userIdentityDescriptor.id !== 'string') {
+			collector.error(localize('requireidstring', "property `{0}` is mandatory and must be of type `string`. Only alphanumeric characters, '_', and '-' are allowed.", 'id'));
+			return false;
+		}
+		if (!(/^[a-z0-9_-]+$/i.test(userIdentityDescriptor.id))) {
+			collector.error(localize('requireidstring', "property `{0}` is mandatory and must be of type `string`. Only alphanumeric characters, '_', and '-' are allowed.", 'id'));
+			return false;
+		}
+		if (typeof userIdentityDescriptor.title !== 'string') {
+			collector.error(localize('requirestring', "property `{0}` is mandatory and must be of type `string`", 'title'));
+			return false;
+		}
+		if (typeof userIdentityDescriptor.iconText !== 'string') {
+			collector.error(localize('requirestring', "property `{0}` is mandatory and must be of type `string`", 'icon'));
+			return false;
+		}
+		return true;
+	}
+
+}
+
+const workbenchRegistry = Registry.as<IWorkbenchContributionsRegistry>(WorkbenchExtensions.Workbench);
+workbenchRegistry.registerWorkbenchContribution(UserIdentityExtensionHandler, LifecyclePhase.Starting);