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Azure Identity plugin for brokered authentication

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This package provides a plugin to the Azure Identity library for JavaScript (@azure/identity) that enables using an authentication broker such as WAM.

An authentication broker is an application that runs on a user’s machine that manages the authentication handshakes and token maintenance for connected accounts. Currently, only the Windows authentication broker, Web Account Manager (WAM), is supported.

Source code | Samples | API reference documentation | [Microsoft Entra ID documentation] (https://zcusa.951200.xyz/entra/identity/)

Getting started

import { useIdentityPlugin } from "@azure/identity";
import { nativeBrokerPlugin } from "@azure/identity-broker";

useIdentityPlugin(nativeBrokerPlugin);

Prerequisites

Install the package

This package is designed to be used with Azure Identity for JavaScript. Install both @azure/identity and this package using npm:

npm install --save @azure/identity
npm install --save @azure/identity-broker

Supported environments

Azure Identity plugins for JavaScript support stable (even numbered) versions of Node.js starting from v18. While the plugins may run in other Node.js versions, no support is guaranteed. @azure/identity-broker does not support browser environments.

Key concepts

If this is your first time using @azure/identity or Microsoft Entra ID, we recommend that you read Using @azure/identity with Microsoft Entra ID first. This document will give you a deeper understanding of the platform and how to configure your Azure account correctly.

Parent window handles

When authenticating with the broker via InteractiveBrowserCredential, a parent window handle is required to ensure that the authentication dialog is shown correctly over the requesting window. In the context of graphical user interfaces on devices, a window handle is a unique identifier that the operating system assigns to each window. For the Windows operating system, this handle is an integer value that serves as a reference to a specific window.

Microsoft account (MSA) passthrough

Microsoft accounts (MSA) are personal accounts created by users to access Microsoft services. MSA passthrough is a legacy configuration which enables users to get tokens to resources which normally don't accept MSA logins. This feature is only available to first-party applications. Users authenticating with an application that is configured to use MSA passthrough can set legacyEnableMsaPassthrough to true inside InteractiveBrowserCredentialNodeOptions.brokerOptions to allow these personal accounts to be listed by WAM.

Redirect URIs

Microsoft Entra applications rely on redirect URIs to determine where to send the authentication response after a user has logged in. To enable brokered authentication through WAM, a redirect URI matching the following pattern should be registered to the application:

ms-appx-web://Microsoft.AAD.BrokerPlugin/{client_id}

Azure Identity plugins

As of @azure/identity version 2.0.0, the Identity client library for JavaScript includes a plugin API. This package (@azure/identity-broker) exports a plugin object that you must pass as an argument to the top-level useIdentityPlugin function from the @azure/identity package. Enable native broker in your program as follows:

import { useIdentityPlugin, InteractiveBrowserCredential } from "@azure/identity";
import { nativeBrokerPlugin } from "@azure/identity-broker";

useIdentityPlugin(nativeBrokerPlugin);
const credential = new InteractiveBrowserCredential({
  brokerOptions: {
    enabled: true,
    parentWindowHandle: new Uint8Array(0), // This should be a handle to the parent window
  },
});

After calling useIdentityPlugin, the native broker plugin is registered to the @azure/identity package and will be available on the InteractiveBrowserCredential that supports WAM broker authentication. This credential has brokerOptions in the constructor options.

Examples

Once the plugin is registered, you can enable WAM broker authentication by passing brokerOptions with an enabled property set to true to a credential constructor. In the following example, we use the InteractiveBrowserCredential.

import { useIdentityPlugin, InteractiveBrowserCredential } from "@azure/identity";
import { nativeBrokerPlugin } from "@azure/identity-broker";

useIdentityPlugin(nativeBrokerPlugin);
const credential = new InteractiveBrowserCredential({
  brokerOptions: {
    enabled: true,
    parentWindowHandle: new Uint8Array(0), // This should be a handle to the parent window
  },
});
// We'll use the Microsoft Graph scope as an example
const scope = "https://graph.microsoft.com/.default";
// Print out part of the access token
console.log((await credential.getToken(scope)).token.substring(0, 10), "...");

For a complete example of using an Electron app for retrieving a window handle, see this sample.

Use the default account for sign-in

When the useDefaultBrokerAccount option is set to true, the credential will attempt to silently use the default broker account. If using the default account fails, the credential will fall back to interactive authentication.

import { useIdentityPlugin, InteractiveBrowserCredential } from "@azure/identity";
import { nativeBrokerPlugin } from "@azure/identity-broker";

useIdentityPlugin(nativeBrokerPlugin);
const credential = new InteractiveBrowserCredential({
  brokerOptions: {
    enabled: true,
    useDefaultBrokerAccount: true,
    parentWindowHandle: new Uint8Array(0), // This should be a handle to the parent window
  },
});
// We'll use the Microsoft Graph scope as an example
const scope = "https://graph.microsoft.com/.default";
// Print out part of the access token
console.log((await credential.getToken(scope)).token.substr(0, 10), "...");

Troubleshooting

See the Azure Identity [troubleshooting guide][https://github.com/Azure/azure-sdk-for-js/blob/@azure/identity-broker_1.1.0/sdk/identity/identity/TROUBLESHOOTING.md] for details on how to diagnose various failure scenarios.

Logging

Enabling logging may help uncover useful information about failures. In order to see a log of HTTP requests and responses, set the AZURE_LOG_LEVEL environment variable to info. Alternatively, logging can be enabled at runtime by calling setLogLevel in the @azure/logger:

import { setLogLevel } from "@azure/logger";

setLogLevel("info");

Next steps

Provide feedback

If you encounter bugs or have suggestions, please open an issue.

Contributing

If you'd like to contribute to this library, see the contributing guide to learn more about how to build and test the code.

Impressions