@microsoft/vscode-azext-utils

VSCode Azure SDK for Node.js - UI Tools (Preview)

This package provides common Azure UI elements for VS Code extensions:

• Telemetry and Error Handling: Displays error messages and adds telemetry to commands/events.
• AzExtTreeDataProvider: Displays an Azure Explorer with Azure Subscriptions and child nodes of your implementation.
• AzExtTreeFileSystem: A virtual file system that supports viewing and editing single files in Azure.

NOTE: This package throws a UserCancelledError if the user cancels an operation. If you do not use registerCommand, you must handle this exception in your extension.

Telemetry and Error Handling

Use registerCommand, registerEvent, or callWithTelemetryAndErrorHandling to consistently display error messages and track commands with telemetry. You must call registerUIExtensionVariables first in your extension's activate() method. The first parameter of the function passed in will always be an IActionContext, which allows you to specify custom telemetry and describes the behavior of this command. The simplest example is to register a command (in this case, refreshing a node):

registerUIExtensionVariables(...);
registerCommand('yourExtension.Refresh', (context: IActionContext, node: AzExtTreeItem) => {
    context.telemetry.properties.customProp = "example prop";
    context.telemetry.measurements.customMeas = 49;
    node.refresh();
});

Here are a few of the benefits this provides:

• Parses Azure errors of the form { "Code": "Conflict", "Message": "This is the actual message" } and only displays the 'Message' property
• Displays single line errors normally and multi-line errors in the output window
• Tracks multiple properties in addition to the common extension properties:
  • result (Succeeded, Failed, or Canceled)
  • duration
  • error

You can also register events. By default, every event is tracked in telemetry. It is highly recommended to leverage the IActionContext.telemetry.suppressIfSuccessful parameter to filter only the events that apply to your extension. For example, if your extension only handles json files in the onDidSaveTextDocument, it might look like this:

registerEvent(
  "yourExtension.onDidSaveTextDocument",
  vscode.workspace.onDidSaveTextDocument,
  async (context: IActionContext, doc: vscode.TextDocument) => {
    context.telemetry.suppressIfSuccessful = true;
    if (doc.fileExtension === "json") {
      context.telemetry.suppressIfSuccessful = false;
      // custom logic here
    }
  }
);

Azure Extension Tree Data Provider

Display Azure Resources

Follow these steps to create your basic Azure Tree:

1. Create an AzExtTreeItem (or AzExtParentTreeItem) describing the items to be displayed under your subscription:

   export class WebAppTreeItem extends AzExtTreeItem {
     public static contextValue: string = "azureWebApp";
     public readonly contextValue: string = WebAppTreeItem.contextValue;
     private readonly _site: Site;
     constructor(parent: AzExtParentTreeItem, site: Site) {
       super(parent);
       this._site = site;
     }
   
     public get id(): string {
       return this._site.id;
     }
   
     public get label(): string {
       return this._site.name;
     }
   }
   

2. Create a SubscriptionTreeItemBase that provides the tree items you just implemented. It must implement at least hasMoreChildrenImpl and loadMoreChildrenImpl:

   NOTE: Methods suffixed with Impl should not be called directly - just implemented.

   export class SubscriptionTreeItem extends SubscriptionTreeItemBase {
       private _nextLink: string | undefined;
   
       public hasMoreChildrenImpl(): boolean {
           return this._nextLink !== undefined;
       }
   
       public async loadMoreChildrenImpl(clearCache: boolean, _context: IActionContext): Promise<WebAppTreeItem[]> {
           if (clearCache) {
               this._nextLink = undefined;
           }
   
           const client: WebSiteManagementClient = createAzureClient(this.root, WebSiteManagementClient);
           const webAppCollection: WebAppCollection = this._nextLink === undefined ?
               await client.webApps.list() :
               await client.webApps.listNext(this._nextLink);
           this._nextLink = webAppCollection.nextLink;
           return webAppCollection.map((site: Site) => new WebAppTreeItem(this, site)));
       }
   }
   

3. Create an AzureAccountTreeItemBase that provides the subscriptions you just implemented. It must implement at least createSubscriptionTreeItem:

   export class AzureAccountTreeItem extends AzureAccountTreeItemBase {
     public createSubscriptionTreeItem(root: ISubscriptionContext): SubscriptionTreeItemBase {
       return new SubscriptionTreeItem(this, root);
     }
   }
   

4. Finally, set up the tree in your extension's activate() method. Instantiate an AzureAccountTreeItem and add it to context.subscriptions since it's a disposable. Then instantiate an AzExtTreeDataProvider, passing in your root tree item and the loadMoreCommandId (which maps the 'Load More...' node to the command registered by your extension).

   const azureAccountTreeItem = new AzureAccountTreeItem();
   context.subscriptions.push(azureAccountTreeItem);
   const treeDataProvider = new AzExtTreeDataProvider(azureAccountTreeItem, "appService.loadMore");
   context.subscriptions.push(vscode.window.createTreeView("azureAppService", { treeDataProvider }));
   

Advanced Scenarios

Non-Azure resources

If your tree displays non-Azure resources you can either provide a different root tree item in the constructor of AzExtTreeDataProvider, or override loadMoreChildrenImpl in AzureAccountTreeItemBase to add items at the same level as subscriptions. The non-Azure tree items can extend AzExtTreeItem and AzExtParentTreeItem (a tree item for an Azure Extension) which are more generic than AzureTreeItem and AzureParentTreeItem.

Tree Item Picker

The above steps will display your Azure Resources, but that's just the beginning. Let's say you implemented a browse function on your WebAppTreeItem that opened the Web App in the browser. In order to make that command work from the VS Code command palette, use the showTreeItemPicker method:

registerCommand('appService.Browse', async (context: IActionContext, treeItem?: WebAppTreeItem) => {
    if (!treeItem) {
        treeItem = await treeDataProvider.showTreeItemPicker(WebAppTreeItem.contextValue, context);
    }

    treeItem.browse();
}));

Create Child Item

For a more advanced scenario, you can also implement the createChildImpl method on your AzExtParentTreeItem. This will ensure the 'Create' option is displayed in the node picker and will automatically display a 'Creating...' item in the tree:

export class WebAppProvider extends SubscriptionTreeItem {
  public async createChildImpl(context: ICreateChildImplContext): Promise<WebAppTreeItem> {
    const webAppName = await vscode.window.showInputBox({ prompt: "Enter the name of your new Web App" });
    context.showCreatingTreeItem(webAppName);
    const newSite: Site | undefined = await createWebApp(webAppName, this.root);
    return new WebAppTreeItem(newSite);
  }
}

Debug Telemetry

If the environment variable DEBUGTELEMETRY is set to a non-empty, non-zero value, then the telemetry reporter used internally by this package will not attempt to send any data. If the value is 'verbose' or 'v', the telemetry will not be sent but will be displayed on the console window.

Display Context Values

With environment variable DEBUGTELEMETRY set to 'v' and settings.json field "azureTools.showContextValues": true, tooltips on treeItems will display their contextValue instead of their conventional tooltip. Set this value to false if you wish to display the normal tooltip while in debug mode. The change in tooltip will then be reflected after the next user action is made through the tree GUI.

Azure Extension Tree File System

NOTE: This replaces BaseEditor, which has been deprecated

A virtual file system that supports viewing and editing single files in Azure. It is not meant to be used as a fully-fledged file system. For now it is based around AzExtTreeItems, but it may be extended to support generic items of any kind if the need arises. Follow these basic steps:

1. Create a new class that extends AzExtTreeFileSystem for your file system. The primary purpose of this class is to describe how the file content is retrieved and updated. See the documentation on the class's types for more information.

2. Set up the file system in your extension's activate() method:

   const fileSystem = new ExampleFileSystem(exampleTree);
   context.subscriptions.push(vscode.workspace.registerFileSystemProvider('exampleScheme', fileSystem));
   

3. Make sure the file system is listed in the activationEvents of your extension's package.json:

   "activationEvents": [
       "onFileSystem:exampleScheme"
   ]
   

License

MIT