Expose the graph API (#11919)

* Exposing the graph API

* Azure managed instance retrival

* Fix compile error

extensions/sql-migration/src/api/azure.ts

@@ -0,0 +1,35 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as vscode from 'vscode';
+import * as azdata from 'azdata';
+import * as azurecore from 'azurecore';
+import { azureResource } from 'azureResource';
+
+async function getAzureCoreAPI(): Promise<azurecore.IExtension> {
+	const api = (await vscode.extensions.getExtension(azurecore.extension.name)?.activate()) as azurecore.IExtension;
+	if (!api) {
+		throw new Error('azure core API undefined for sql-migration');
+	}
+	return api;
+}
+
+export type Subscription = azureResource.AzureResourceSubscription;
+export async function getSubscriptions(account: azdata.Account): Promise<Subscription[]> {
+	const api = await getAzureCoreAPI();
+	const subscriptions = await api.getSubscriptions(account, false);
+
+	return subscriptions.subscriptions;
+}
+
+export type AzureProduct = azureResource.AzureGraphResource;
+export type SqlManagedInstance = azureResource.AzureSqlManagedInstanceResource;
+export async function getAvailableManagedInstanceProducts(account: azdata.Account, subscription: Subscription): Promise<SqlManagedInstance[]> {
+	const api = await getAzureCoreAPI();
+
+	const result = await api.runGraphQuery<azureResource.AzureSqlManagedInstanceResource>(account, subscription, false, 'where type == "microsoft.sql/managedinstances"');
+
+	return result.resources;
+}