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Add authentication to your bot via Azure Bot Service

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APPLIES TO: SDK v3

This tutorial uses new bot authentication capabilities in Azure Bot Service, providing features to make it easier to develop a bot that authenticates users to various identity providers such as Azure AD (Azure Active Directory), GitHub, Uber, and so on. These updates also take steps towards an improved user experience by eliminating the magic code verification for some clients.

Prior to this, your bot needed to include OAuth controllers and login links, store the target client IDs and secrets, and perform user token management.

Now, bot developers no longer need to host OAuth controllers or manage the token life-cycle, as all of this can now be done by the Azure Bot Service.

The features include:

  • Improvements to the channels to support new authentication features, such as new WebChat and DirectLineJS libraries to eliminate the need for the 6-digit magic code verification.
  • Improvements to the Azure Portal to add, delete, and configure connection settings to various OAuth identity providers.
  • Support for a variety of out-of-the-box identity providers including Azure AD (both v1 and v2 endpoints), GitHub, and others.
  • Updates to the C# and Node.js Bot Framework SDKs to be able to retrieve tokens, create OAuthCards and handle TokenResponse events.
  • Samples for how to make a bot that authenticates to Azure AD (v1 and v2 endpoints) and to GitHub.

You can extrapolate from the steps in this article to add such features to an existing bot. The following are sample bots that demonstrate the new authentication features

Sample BotBuilder version Description
AadV1Bot v3 Demonstrates OAuthCard support in the v3 C# SDK, using the Azure AD v1 endpoint
AadV2Bot v3 Demonstrates OAuthCard support in the v3 C# SDK, using the Azure AD v2 endpoint
GitHubBot v3 Demonstrates OAuthCard support in the v3 C# SDK, using GitHub
BasicOAuth v3 Demonstrates OAuth 2.0 support in the v3 C# SDK

Note

The authentication features also work with Node.js with BotBuilder v3. However, this article covers just sample C# code.

For additional information and support, refer to Bot Framework additional resources.

Overview

This tutorial creates a sample bot that connects to the Microsoft Graph using an Azure AD v1 or v2 token. As part of this process, you'll use code from a GitHub repo, and this tutorial describes how to set that up, including the bot application.

To complete these steps, you will need Visual Studio 2017, npm, node, and git installed. You should also have some familiarity with Azure, OAuth 2.0, and bot development.

Once you finish, you will have a bot that can respond to a few simple tasks against an Azure AD application, such as checking and sending an email, or displaying who you are and who your manager is. To do this, your bot will use a token from an Azure AD application against the Microsoft.Graph library.

The final section breaks down some of the bot code

Create your bot and an authentication application

You need to create a registration bot where you'll set the messaging endpoint to your deployed bot's code, and you need to create an Azure AD (either v1 or v2) application to allow your bot to access Office 365.

Note

These authentication features work with other types of bots. However this tutorial uses a registration only bot.

Register an application in Azure AD

You need an Azure AD application that your bot can use as an identity provider to connect to the Microsoft Graph API.

For this bot you can use Azure AD v1 or v2 endpoints. For information about the differences between the v1 and v2 endpoints, see the v1-v2 comparison and the Azure AD v2.0 endpoint overview.

Create an Azure AD identity provider application

Use these steps to create a new Azure AD application. You can use the v1 or v2 endpoints with the app that you create.

Tip

You will need to create and register the Azure AD application in a tenant in which you can consent to delegate permissions requested by an application.

  1. Open the [Azure Active Directory][azure-aad-blade] panel in the Azure portal. If you are not in the correct tenant, click Switch directory to switch to the correct tenant. (For instruction on creating a tenant, see Access the portal and create a tenant.)

  2. Open the App registrations panel.

  3. In the App registrations panel, click New registration.

  4. Fill in the required fields and create the app registration.

    1. Name your application.

    2. Select the Supported account types for your application.

    3. For the Redirect URI

      1. Select Web.
      2. Set the URL to https://token.botframework.com/.auth/web/redirect.

    4. Click Register.

      • Once it is created, Azure displays the Overview page for the app.
      • Record the Application (client) ID value. You will use this value later as the Client id when you register your Azure AD application with your bot.
      • Also record the Directory (tenant) ID value. You will also use this to register this application with your bot.

    Note

When the supported account types is set to single tenant, if you use a personal subscription instead of a Microsoft account the emulator will send the error: The bot's Microsoft App ID or Microsoft App Password is incorrect.. > In this case, the supported account types must be set to Accounts in any organizational directory (Any Azure AD directory - Multitenant) and personal Microsoft accounts (e.g. Xbox).

  1. In the navigation pane, click Certificates & secrets to create a secret for your application.

    1. Under Client secrets, click New client secret.
    2. Add a description to identify this secret from others you might need to create for this app, such as bot login.
    3. Set Expires to Never.
    4. Click Add.
    5. Before leaving this page, record the secret. You will use this value later as the Client secret when you register your Azure AD application with your bot.

  2. In the navigation pane, click API permissions to open the API permissions panel. It is a best practice to explicitly set the API permissions for the app.

    1. Click Add a permission to show the Request API permissions pane.

    2. For this sample, select Microsoft APIs and Microsoft Graph.

    3. Choose Delegated permissions and make sure the permissions you need are selected. This sample requires theses permissions.

      Note

      Any permission marked as ADMIN CONSENT REQUIRED will require both a user and a tenant admin to login, so for your bot tend to stay away from these.

      • openid
      • profile
      • Mail.Read
      • Mail.Send
      • User.Read
      • User.ReadBasic.All

    4. Click Add permissions. (The first time a user accesses this app through the bot, they will need to grant consent.)

You now have an Azure AD application configured.

Create your bot on Azure

Create a Bot Channels Registration using the Azure Portal.

Register your Azure AD application with your bot

The next step is to register with your bot the Azure AD application that you just created.

  1. Navigate to your bot's resource page on the Azure Portal.

  2. Click Settings.

  3. Under OAuth Connection Settings near the bottom of the page, click Add Setting.

  4. Fill in the form as follows:

    1. For Name, enter a name for your connection. You'll use this name in your bot code.

    2. For Service Provider, select Azure Active Directory. Once you select this, the Azure AD-specific fields will be displayed.

    3. For Client id, enter the application (client) ID that you recorded for your Azure AD v1 application.

    4. For Client secret, enter the secret that you created to grant the bot access to the Azure AD app.

    5. For Grant Type, enter authorization_code.

    6. For Login URL, enter https://login.microsoftonline.com.

    7. For Tenant ID, enter the directory (tenant) ID that your recorded earlier for your Azure AD app.

      This will be the tenant associated with the users who can be authenticated.

    8. For Resource URL, enter https://graph.microsoft.com/.

    9. Leave Scopes blank.

  5. Click Save.

Note

These values enable your application to access Office 365 data via the Microsoft Graph API.

To test your connection

  1. Open the connection you just created.
  2. Click Test Connection at the top of the Service Provider Connection Setting pane.
  3. The first time, this should open a new browser tab listing the permissions your app is requesting and prompt you to accept.
  4. Click Accept.
  5. This should then redirect you to a Test Connection to `' Succeeded page.

Prepare the bot sample code

  1. Clone the github repository at https://github.com/Microsoft/BotBuilder.

  2. Open and build the solution, BotBuilder\CSharp\Microsoft.Bot.Builder.sln.

  3. Close that solution and open, BotBuilder\CSharp\Samples\Microsoft.Bot.Builder.Samples.sln.

  4. Set the start up project.

    • For a bot that uses the v1 Azure AD application, use the Microsoft.Bot.Sample.AadV1Bot project.
    • For a bot that uses the v2 Azure AD application, use the Microsoft.Bot.Sample.AadV2Bot project.

  5. Open the Web.config file, and modify the app settings as follows:

    1. Set the ConnectionName to the value you used when you configured your bot's OAuth 2.0 connection setting.
    2. Set the MicrosoftAppId value to your bot's app ID.
    3. Set the MicosoftAppPassword value to your bot's secret.

    Important

    Depending on the characters in your secret, you may need to XML escape the password. For example, any ampersands (&) will need to be encoded as &.

    <appSettings>
    <add key="ConnectionName" value="<your-AAD-connection-name>"/>
    <add key="MicrosoftAppId" value="<your-bot-appId>" />
    <add key="MicrosoftAppPassword" value="<your-bot-password>" />
</appSettings>

    To obtain the Microsoft app ID and Microsoft app password values, see Get registration password.

    Note

    You could now publish this bot code to your Azure subscription (right-click on the project and choose Publish), but it is not necessary for this tutorial. You would need to set up a publishing configuration that uses the application and hosting plan that you used when configuration the bot in the Azure Portal.

Use the Emulator to test your bot

You will need to install the Bot Emulator to test your bot locally. You can use the v3 or v4 Emulator.

  1. Start your bot (with or without debugging).

  2. Note the localhost port number for the page. You will need this information to interact with your bot.

  3. Start the Emulator.

  4. Connect to your bot.

    If you haven't configured the connection already, provide the address and your bot's Microsoft app ID and password. Add /api/messages to the bot's URL. Your URL will look something like http://localhost:portNumber/api/messages.

  5. Type help to see a list of available commands for the bot, and test the authentication features.

  6. Once you've signed in, you don't need to provide your credentials again until you sign out.

  7. To sign out, and cancel your authentication, type signout.

Note

Bot authentication requires use of the Bot Connector Service. The service accesses the bot channels registration information for your bot, which is why you need to set your bot's messaging endpoint on the portal. Authentication also requires the use of HTTPS, which is why you needed to create an HTTPS forwarding address for your bot running locally.

Notes on the token retrieval flow

When a user asks the bot to do something that requires the bot to have the user logged in, the bot can use the Microsoft.Bot.Builder.Dialogs.GetTokenDialog to initiate retrieving a token for a given connection. The next couple of snippets are taken from the GetTokenDialog class.

Check for a cached token

In this code, first the bot does a quick check to determine if the Azure Bot Service already has a token for the user (which is identified by the current Activity sender) and the given ConnectionName (which is the connection name used in configuration). Azure Bot Service will either already have a token cached or it will not. The call to GetUserTokenAsync performs this ‘quick check'. If Azure Bot Service has a token and returns it, the token can immediately be used. If Azure Bot Service does not have a token, this method will return null. In this case, the bot can send a customized OAuthCard for the user to login.

// First ask Bot Service if it already has a token for this user
var token = await context.GetUserTokenAsync(ConnectionName).ConfigureAwait(false);
if (token != null)
{
    // use the token to do exciting things!
}
else
{
    // If Bot Service does not have a token, send an OAuth card to sign in
    await SendOAuthCardAsync(context, (Activity)context.Activity);
}

Send an OAuthCard to the user

You can customize the OAuthCard with whatever text and button text you want. The important pieces are:

  • Set the ContentType to OAuthCard.ContentType.
  • Set the ConnectionName property to the name of the connection you want to use.
  • Include one button with a CardAction of Type ActionTypes.Signin; note that you do not need to specify any value for the sign in link.

At the end of this call, the bot needs to "wait for the token" to come back. This waiting takes place on the main Activity stream because there could be a lot the user needs to do to sign-in.

private async Task SendOAuthCardAsync(IDialogContext context, Activity activity)
{
    await context.PostAsync($"To do this, you'll first need to sign in.");

    var reply = await context.Activity.CreateOAuthReplyAsync(_connectionName, _signInMessage, _buttonLabel).ConfigureAwait(false);
    await context.PostAsync(reply);

    context.Wait(WaitForToken);
}

Wait for a TokenResponseEvent

In this code the Bot's dialog class is waiting for a TokenResponseEvent (more about how this is routed to the Dialog stack is below). The WaitForToken method first determines if this event was sent. If it was sent, it can be used by the bot. If it was not, the WaitForToken method takes whatever text was sent to the bot and passes it to GetUserTokenAsync. The reason for this is that some clients (like WebChat) do not need the Magic Code verification code and can directly send the Token in the TokenResponseEvent. Other clients still require the magic code (like Facebook or Slack). The Azure Bot Service will present these clients with a six digit magic code and ask the user to type this into the chat window. While not ideal, this is the 'fall back' behavior and so if WaitForToken receives a code, the bot can send this code to the Azure Bot Service and get a token back. If this call also fails, then you can decide to report an error, or do something else. In most cases though, the bot will now have a user token.

If you look in the MessageController.cs file, you'll see that Event activities of this type are also routed to the dialog stack.

private async Task WaitForToken(IDialogContext context, IAwaitable<object> result)
{
    var activity = await result as Activity;

    var tokenResponse = activity.ReadTokenResponseContent();
    if (tokenResponse != null)
    {
        // Use the token to do exciting things!
    }
    else
    {
        if (!string.IsNullOrEmpty(activity.Text))
        {
            tokenResponse = await context.GetUserTokenAsync(ConnectionName,
                                                               activity.Text);
            if (tokenResponse != null)
            {
                // Use the token to do exciting things!
                return;
            }
        }
        await context.PostAsync($"Hmm. Something went wrong. Let's try again.");
        await SendOAuthCardAsync(context, activity);
    }
}

Message controller

On subsequent calls to the bot, notice that the token is never cached by this sample bot. This is because the bot can always ask the Azure Bot Service for the token. This avoids the bot needing to manage the token life-cycle, refresh the token, etc, as Azure Bot Service does all of this for you.

else if(message.Type == ActivityTypes.Event)
{
    if(message.IsTokenResponseEvent())
    {
        await Conversation.SendAsync(message, () => new Dialogs.RootDialog());
    }
}

Additional resources

Bot Framework SDK