Throw Better Error when running registries commands when No Registries are Connected

package.json

@@ -3007,7 +3007,7 @@
         "@microsoft/vscode-azext-azureutils": "^2.0.0",
         "@microsoft/vscode-azext-utils": "^2.1.1",
         "@microsoft/vscode-container-client": "^0.1.0",
-        "@microsoft/vscode-docker-registries": "^0.1.1",
+        "@microsoft/vscode-docker-registries": "file:../vscode-docker-extensibility/packages/vscode-docker-registries/microsoft-vscode-docker-registries-0.1.2.tgz",
         "dayjs": "^1.11.7",
         "dockerfile-language-server-nodejs": "^0.11.0",
         "fs-extra": "^11.1.1",

src/commands/registries/genericV2/addTrackedGenericV2Registry.ts

@@ -8,7 +8,17 @@ import { ext } from "../../../extensionVariables";
 import { UnifiedRegistryItem } from "../../../tree/registries/UnifiedRegistryTreeDataProvider";
 
 export async function addTrackedGenericV2Registry(context: IActionContext, node?: UnifiedRegistryItem<unknown>): Promise<void> {
-    await ext.genericRegistryV2DataProvider.addTrackedRegistry();
+    const root = ext.genericRegistryV2DataProvider.getRoot();
+    const registries = await ext.genericRegistryV2DataProvider.getRegistries(root);
+
+    if (registries?.length > 0) {
+        // if there are already registries, add a new registry to the existing root node
+        await ext.genericRegistryV2DataProvider.addTrackedRegistry();
+    } else {
+        // if there are no registries, connect as usual
+        await ext.registriesTree.connectRegistryProvider(ext.genericRegistryV2DataProvider);
+    }
+
     // don't wait
     void ext.registriesTree.refresh();
 }

src/tree/registries/ConnectRegistryTreeItem.ts

@@ -0,0 +1,33 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See LICENSE.md in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { CommonRegistryItem, isCommonRegistryItem } from '@microsoft/vscode-docker-registries';
+import * as vscode from 'vscode';
+import { UnifiedRegistryItem } from "./UnifiedRegistryTreeDataProvider";
+
+export const ConnectRegistryContextValue: string = 'connectregistry';
+
+export function isConnectRegistryTreeItem(item: unknown): item is UnifiedRegistryItem<CommonRegistryItem> {
+    return isCommonRegistryItem(item) && item.type === ConnectRegistryContextValue;
+}
+
+/**
+ * Creates a tree item that can be used to connect a new registry
+ */
+export function getConnectRegistryTreeItem(): UnifiedRegistryItem<CommonRegistryItem> {
+    return {
+        provider: undefined,
+        parent: undefined,
+        wrappedItem: {
+            label: vscode.l10n.t('Connect Registry...'),
+            type: ConnectRegistryContextValue,
+            iconPath: new vscode.ThemeIcon('plug'),
+            command: {
+                command: 'vscode-docker.registries.connectRegistry'
+            },
+            parent: undefined
+        }
+    };
+}

src/tree/registries/UnifiedRegistryTreeDataProvider.ts

@@ -2,6 +2,7 @@ import { CommonRegistry, CommonRegistryRoot, RegistryDataProvider, isCommonRegis
 import * as vscode from 'vscode';
 import { ext } from '../../extensionVariables';
 import { isAzureSubscriptionRegistryItem } from './Azure/AzureRegistryDataProvider';
+import { getConnectRegistryTreeItem } from './ConnectRegistryTreeItem';
 
 interface WrappedElement {
     // eslint-disable-next-line @typescript-eslint/naming-convention
@@ -85,18 +86,8 @@ export class UnifiedRegistryTreeDataProvider implements vscode.TreeDataProvider<
 
             // if there are no connected providers, show a command to connect one
             if (unifiedRegistryItems.length === 0) {
-                unifiedRegistryItems.push({
-                    provider: undefined,
-                    wrappedItem: {
-                        label: vscode.l10n.t('Connect Registry...'),
-                        type: 'connectregistry',
-                        iconPath: new vscode.ThemeIcon('plug'),
-                        command: {
-                            command: 'vscode-docker.registries.connectRegistry'
-                        }
-                    },
-                    parent: undefined,
-                });
+                const connectRegistryItem = getConnectRegistryTreeItem();
+                unifiedRegistryItems.push(connectRegistryItem);
             }
         }
 

src/utils/registryExperience.ts

@@ -3,10 +3,11 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import { AzureWizardPromptStep, ContextValueFilterQuickPickOptions, GenericQuickPickStep, IActionContext, PickFilter, QuickPickWizardContext, RecursiveQuickPickStep, runQuickPickWizard } from '@microsoft/vscode-azext-utils';
+import { AzureWizardPromptStep, ContextValueFilterQuickPickOptions, GenericQuickPickStep, IActionContext, PickFilter, QuickPickWizardContext, RecursiveQuickPickStep, UserCancelledError, runQuickPickWizard } from '@microsoft/vscode-azext-utils';
 import { CommonRegistryItem } from '@microsoft/vscode-docker-registries';
-import { TreeItem, l10n } from 'vscode';
+import { MessageItem, TreeItem, commands, l10n, window } from 'vscode';
 import { ext } from '../extensionVariables';
+import { isConnectRegistryTreeItem } from '../tree/registries/ConnectRegistryTreeItem';
 import { UnifiedRegistryItem, UnifiedRegistryTreeDataProvider } from '../tree/registries/UnifiedRegistryTreeDataProvider';
 
 export interface RegistryFilter {
@@ -27,6 +28,22 @@ export interface RegistryExperienceOptions extends Partial<ContextValueFilterQui
 }
 
 export async function registryExperience<TNode extends CommonRegistryItem>(context: IActionContext, options?: RegistryExperienceOptions): Promise<UnifiedRegistryItem<TNode>> {
+    const registryRoots = await ext.registriesTree.getChildren();
+    // if there are no registry providers, throw an error with option to connect a registry provider
+    if (registryRoots.length === 0 || (registryRoots.length === 1 && isConnectRegistryTreeItem(registryRoots[0].wrappedItem))) {
+        const add: MessageItem = { title: l10n.t('Connect Registry...') };
+        void window.showErrorMessage(
+            l10n.t('No registry providers are connected. Please connect a registry provider to continue.'),
+            ...[add])
+            .then((result) => {
+                if (result === add) {
+                    void commands.executeCommand('vscode-docker.registries.connectRegistry');
+                }
+            });
+
+        throw new UserCancelledError();
+    }
+
     // get the registry provider unified item
     const promptSteps: AzureWizardPromptStep<QuickPickWizardContext>[] = [
         new RegistryQuickPickStep(ext.registriesTree, options)