2-sign-in-b2c

A Node.js & Express web app authenticating users against Azure AD B2C with MSAL Node

1. Overview
2. Scenario
3. Contents
4. Prerequisites
5. Setup
6. Registration
7. Running the sample
8. Explore the sample
9. More information
10. Community Help and Support
11. Contributing

Overview

This sample demonstrates a Node.js & Express web application that authenticates users against Azure AD B2C, with the help of Microsoft Authentication Library for Node.js (MSAL Node). In doing so, it illustrates authentication concepts such as OpenID scopes, ID Tokens, ID Token validation, user-flows and more.

Scenario

1. The client application uses MSAL Node (via msal-node-wrapper) to obtain an ID Token from Azure AD B2C.
2. The ID Token proves that the user has successfully authenticated against Azure AD B2C.

Contents

File/folder	Description
AppCreationScripts/	Contains Powershell scripts to automate app registration.
ReadmeFiles/	Contains illustrations and screenshots.
App/authConfig.js	Authentication parameters and settings
App/app.js	Application entry point.

Prerequisites

• Node.js must be installed to run this sample.
• Visual Studio Code is recommended for running and editing this sample.
• A modern web browser. This sample uses ES6 conventions and will not run on Internet Explorer.
• An Azure AD B2C tenant. For more information see: How to get an Azure AD B2C tenant
• A user account in your Azure AD B2C tenant.

Setup

Step 1: Clone or download this repository

From your shell or command line:

    git clone https://github.com/Azure-Samples/ms-identity-javascript-nodejs-tutorial.git

or download and extract the repository .zip file.

⚠️ To avoid path length limitations on Windows, we recommend cloning into a directory near the root of your drive.

Step 2: Install project dependencies

Locate the root of the sample folder. Then:

    cd 1-Authentication\2-sign-in-b2c\App
    npm install

Registration

Choose the Azure AD tenant where you want to create your applications

1. Sign in to the Azure portal.
2. If your account is present in more than one Azure AD B2C tenant, select your profile at the top right corner in the menu on top of the page, and then switch directory to change your portal session to the desired Azure AD B2C tenant.

Create User Flows

Please refer to: Tutorial: Create user flows in Azure Active Directory B2C

Add External Identity Providers

Please refer to: Tutorial: Add identity providers to your applications in Azure Active Directory B2C

Register the client app (msal-node-webapp)

1. Navigate to the Azure portal and select the Azure AD B2C service.
2. Select the App Registrations blade on the left, then select New registration.
3. In the Register an application page that appears, enter your application's registration information:
   • In the Name section, enter a meaningful application name that will be displayed to users of the app, for example msal-node-webapp.
   • Under Supported account types, select Accounts in any identity provider or organizational directory (for authenticating users with user flows).
   • In the Redirect URI (optional) section, select Web in the combo-box and enter the following redirect URI: http://localhost:4000/redirect.
4. Select Register to create the application.
5. In the app's registration screen, find and note the Application (client) ID. You use this value in your app's configuration file(s) later in your code.
6. Select Save to save your changes.
7. In the app's registration screen, select the Certificates & secrets blade in the left to open the page where you can generate secrets and upload certificates.
8. In the Client secrets section, select New client secret:
   • Type a key description (for instance app secret),
   • Select one of the available key durations (6 months, 12 months or Custom) as per your security posture.
   • The generated key value will be displayed when you select the Add button. Copy and save the generated value for use in later steps.
   • You'll need this key later in your code's configuration files. This key value will not be displayed again, and is not retrievable by any other means, so make sure to note it from the Azure portal before navigating to any other screen or blade.

   ⚠️ For enhanced security, consider using certificates instead of client secrets. See: How to use certificates instead of secrets.

Configure the client app (msal-node-webapp) to use your app registration

Open the project in your IDE (like Visual Studio or Visual Studio Code) to configure the code.

In the steps below, "ClientID" is the same as "Application ID" or "AppId".

1. Open the App/authConfig.js file.
2. Find the key clientId and replace the existing value with the application ID (clientId) of msal-node-webapp app copied from the Azure portal.
3. Find the key authority and replace it with the authority string of your policies/user-flows, e.g. https://fabrikamb2c.b2clogin.com/fabrikamb2c.onmicrosoft.com/b2c_1_susi.
4. Find the key clientSecret and replace the existing value with the key you saved during the creation of msal-node-webapp copied from the Azure portal.
5. Find the key redirectUri and replace the existing value with the Redirect URI for msal-node-webapp. (by default http://localhost:4000/redirect).

ℹ️ For redirectUri, you can simply enter the path component of the URI instead of the full URI. For example, instead of http://localhost:4000/redirect, you can simply enter /redirect. This may come in handy in deployment scenarios.

1. Open the App/app.js file.
2. Find the string ENTER_YOUR_SECRET_HERE and replace it with a secret that will be used when encrypting your app's session using the express-session package.

Running the sample

Locate the root of the sample folder. Then:

    npm start

Explore the sample

1. Open your browser and navigate to http://localhost:4000.
2. Click the sign-in button on the top right corner.
3. Once signed in, select the ID button to see some of the claims in your ID token.

ℹ️ Did the sample not work for you as expected? Then please reach out to us using the GitHub Issues page.

We'd love your feedback!

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More information

• What is Azure Active Directory B2C?
• Application types that can be used in Active Directory B2C
• Recommendations and best practices for Azure Active Directory B2C
• Azure AD B2C session
• Initialize client applications using MSAL.js
• Single sign-on with MSAL.js
• Handle MSAL.js exceptions and errors
• Logging in MSAL.js applications
• Pass custom state in authentication requests using MSAL.js
• Prompt behavior in MSAL.js interactive requests
• Use MSAL.js to work with Azure AD B2C

For more information about how OAuth 2.0 protocols work in this scenario and other scenarios, see Authentication Scenarios for Azure AD.

Community Help and Support

Use Stack Overflow to get support from the community. Ask your questions on Stack Overflow first and browse existing issues to see if someone has asked your question before. Make sure that your questions or comments are tagged with [azure-active-directory azure-ad-b2c ms-identity adal msal].

If you find a bug in the sample, raise the issue on GitHub Issues.

To provide feedback on or suggest features for Azure Active Directory, visit User Voice page.

Contributing

If you'd like to contribute to this sample, see CONTRIBUTING.MD.

This project has adopted the Microsoft Open Source Code of Conduct. For more information, see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.