# Challenge 1: Receive an ID Token in a Fragment URL

# Here is what you'll learn 🎯

  • How to register an application in Azure AD
  • How to create an Open ID Connect request to authenticate an user
  • How to receive an ID token in a Fragment URL (opens new window) for receiving information about the authenticated user

This is very similar to Challenge 0, except that this time we will receive the id_token through a fragment URL instead of it being in the body.

# Table Of Contents

  1. Create an AAD Application
  2. Run the Token Echo Server
  3. Create an Authentication Request
  4. Wrap-Up
  5. Cleanup

# Create an AAD Application

Before you can authenticate an user you have to register an application in your AAD tenant.

# Azure CLI

az ad app create --display-name challengeidtokenfragment --reply-urls http://localhost:5001/api/tokenechofragment --identifier-uris https://challengeidtokenfragment

Retrieve and note the ID of your current AAD tenant via:

az account show 

# Run the Token Echo Server

Open another shell and run the Token Echo Server from day5/apps/token-echo-server in this repository. This helper ASP.NET Core tool is used to echo the token issued by your Azure AD. The tool is listening on port 5001 on your local machine. Tokens are accepted on the route http://localhost:5001/api/tokenechofragment. This is why we initially registered an AAD application with a reply url pointing to http://localhost:5001/api/tokenechofragment.

dotnet run

# Create an Authentication Request

Replace TENANT_ID with your TenantId and APPLICATION_ID with your ApplicationId. Open a browser and paste the modified request.

https://login.microsoftonline.com/TENANT_ID/oauth2/v2.0/authorize?
client_id=APPLICATION_ID
&response_type=id_token
&redirect_uri=http%3A%2F%2Flocalhost%3A5001%2Fapi%2Ftokenechofragment
&response_mode=fragment
&scope=openid%20profile
&nonce=1234

Copy the id_token value from your browser's address bar, go to https://jwt.ms (opens new window) and paste the token. Take a minute and have a look at the decoded token.

TIP

📝 If you need further information about the issued claims take a look here (opens new window).

# Wrap-Up

This challenge showed how to create a new application in Azure AD and how an user can be authenticated using the Open ID Connect protocol. The full process is described here (opens new window).

# Cleanup

Remove the created resources via the Azure CLI:

az ad app delete --id <applicationid>

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