Adding proposed external uri opener API

For #109277

src/vs/workbench/api/browser/mainThreadUriOpeners.ts

@@ -0,0 +1,63 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { CancellationToken } from 'vs/base/common/cancellation';
+import { Schemas } from 'vs/base/common/network';
+import { URI } from 'vs/base/common/uri';
+import { IOpener, IOpenerService, OpenExternalOptions, OpenInternalOptions } from 'vs/platform/opener/common/opener';
+import { ExtHostContext, ExtHostUriOpenersShape, IExtHostContext, MainContext, MainThreadUriOpenersShape } from 'vs/workbench/api/common/extHost.protocol';
+import { IExtensionService } from 'vs/workbench/services/extensions/common/extensions';
+import { extHostNamedCustomer } from '../common/extHostCustomers';
+
+
+@extHostNamedCustomer(MainContext.MainThreadUriOpeners)
+export class MainThreadUriOpeners implements MainThreadUriOpenersShape, IOpener {
+
+	private readonly proxy: ExtHostUriOpenersShape;
+	private readonly handlers = new Set<number>();
+
+	constructor(
+		context: IExtHostContext,
+		@IOpenerService private readonly openerService: IOpenerService,
+		@IExtensionService private readonly extensionService: IExtensionService,
+	) {
+		this.proxy = context.getProxy(ExtHostContext.ExtHostUriOpeners);
+
+		this.openerService.registerOpener(this);
+	}
+
+	async open(
+		target: string | URI,
+		options?: OpenInternalOptions | OpenExternalOptions
+	): Promise<boolean> {
+		const targetUri = typeof target === 'string' ? URI.parse(target) : target;
+
+		// Currently we only allow openers for http and https urls
+		if (targetUri.scheme !== Schemas.http && targetUri.scheme !== Schemas.https) {
+			return false;
+		}
+
+		await this.extensionService.activateByEvent(`onUriOpen:${targetUri.scheme}`);
+
+		// No handlers so no point in making a rount trip
+		if (!this.handlers.size) {
+			return false;
+		}
+
+		return await this.proxy.$openUri(targetUri, CancellationToken.None);
+	}
+
+	async $registerUriOpener(handle: number): Promise<void> {
+		this.handlers.add(handle);
+	}
+
+	async $unregisterUriOpener(handle: number): Promise<void> {
+		this.handlers.delete(handle);
+	}
+
+	dispose(): void {
+		this.handlers.clear();
+	}
+}