Affinidi Login with Python

The Affinidi Login is a passwordless authentication solution that verifies user identity using Affinidi Vault as the identity provider managed by the end-user.

In this lab, we will use the Django framework with Authlib from the available sample applications to take you through the step-by-step guide for creating a Login Configuration and setting up the application to implement passwordless authentication for end-users.

Before you begin

1. Set up Affinidi Vault account. Follow the guide below if you haven’t set it up yet.

Set up Affinidi Vault

1. Set up an Affinidi Vault account using the web app or install the mobile app .

The same installation steps for mobile app.

2. Click on Start if you are creating a new account, or click on Restore from Backup if you have an existing backup of your Affinidi Vault.

Use this guide to learn how to migrate your existing Affinidi Vault account.

3. Secure your Vault by providing a passphrase. Use this passphrase to unlock your Vault.

3. Provide your Email Address to verify with OTP.

After successfully providing the OTP, you are redirected to your Affinidi Vault dashboard.

Vault Passphrase

Remember to keep your passphrase in a secure location since it cannot be retrieved if forgotten, even with your backup. If you forget it, you must setup a new Vault.

2. Get the Redirect URI of your application for OIDC. This is the URI configured on your Login Configuration to receive the idToken after successful authorisation.

3. Optionally, Install the Affinidi CLI. Follow the guide below if it hasn’t been installed.

Set up Affinidi CLI

1. Download and install NodeJS on your machine if you haven’t set it up yet.

Node Version

Affinidi CLI requires Node version 18 and above.

2. Install Affinidi CLI using Node Package Manager (npm).

npm install -g @affinidi/cli

3. Verify that the installation is successful.

affinidi --version

4. Install Python on your machine if you haven’t installed yet using this guide .

Download Application

You can clone this sample application from our Github and start exploring how to integrate Affinidi Login to provide a passwordless login experience for your end-users.

Create Login Configuration

To create a Login Configuration, you can either use Affinidi CLI or  Affinidi Portal.

Expand the section below for your preferred method:

Django Sample App Settings:

Name: Django App

Redirect URIs: http://localhost:8000/callback

affinidi start

affinidi login create-config --name='Django App' --redirect-uris='http://localhost:8000/callback'

Using Affinidi Portal

1. Go to  Affinidi Login under the Services section.

2. Click on the Create Login Configuration and provide the required details.

• Name is the string that describes your login configuration.
• Redirect URIs is the URL on your application where the user gets redirected after the successful authentication.

3. Click on create and confirm if all the details are correct.

4. After confirming the details, another popup shows the Client ID and Client Secret for your Login Configuration. Copy the generated Client Credentials and use them to integrate with Affinidi Login.

5. After copying the Client ID and Client Secret and closing the popup, you are redirected back to the Affinidi Login page.

Login Configuration uses the default Presentation Definition (presentationDefinition) and ID Token Mapping (idTokenMapping) that is used to request the user’s email address during the authentication flow.

Learn more about customising the Presentation Definition and ID Token using this guide.

Set up the Sample Application

After creating the Login Configuration required to set up the sample application. Let’s start setting up the Django application by configuring the following settings:

Configure Env Variables

Create the .env file using the following command:

cp .env.example .env

Set the environment variables based on the auth credentials received from the Login Configuration created earlier:

{
  "auth": {
    "clientId": "<AUTH.CLIENT_ID>",
    "clientSecret": "<AUTH.CLIENT_SECRET>",
    "issuer": "https://<PROJECT_ID>.apse1.login.affinidi.io"
  }
}

Set the following fields in the .env file

PROVIDER_CLIENT_ID="<AUTH.CLIENT_ID>"
PROVIDER_CLIENT_SECRET="<AUTH.CLIENT_SECRET>"
PROVIDER_ISSUER="<AUTH.CLIENT_ISSUER>"

Install Dependencies

pip install -r requirements.txt

It will install all the required libraries for the sample application.

Apply Settings

Run the migration script to propagate changes to the model:

python manage.py migrate

Run Sample Application

Run the application using the runserver command:

python manage.py runserver

After successfully running the command, go to http://localhost:8000 to access the page with the Affinidi Login button.

Key Changes to Sample Application

AuthLib for OIDC

In this sample app, we have defined the requirements.txt file to import the AuthLib library, enabling OAuth and OpenID Connect to integrate Affinidi Login to authenticate users.

Django==4.2.6
Authlib==1.2.1
requests==2.31.0
python-dotenv==1.0.0

Enabling Affinidi Login

In views.py, we have imported AuthLib and registered affinidi as the Auth provider for our sample application. In the oauth.register call, we have provided the client credentials and issuer URL generated after creating Login Configuration.

import json
from authlib.integrations.django_client import OAuth
from django.conf import settings
from django.shortcuts import redirect, render, redirect
from django.urls import reverse

oauth = OAuth()

oauth.register(
    "affinidi",
    client_id=settings.PROVIDER_CLIENT_ID,
    client_secret=settings.PROVIDER_CLIENT_SECRET,
    client_kwargs={
        'scope': 'openid offline_access',
        'token_endpoint_auth_method': 'client_secret_post',
    },
    server_metadata_url=f"{settings.PROVIDER_ISSUER}/.well-known/openid-configuration",
)

def login(request):
    redirect_uri = request.build_absolute_uri(reverse('callback'))
    return oauth.affinidi.authorize_redirect(request, redirect_uri)

def callback(request):
    token = oauth.affinidi.authorize_access_token(request)
    request.session["user"] = token['userinfo']
    return redirect(request.build_absolute_uri(reverse("index")))

def logout(request):
    request.session.pop('user', None)
    return redirect('/')

def index(request):
    user = request.session.get("user")
    if user:
        if user["custom"] and len(user["custom"][1])>0:
            email = user["custom"][1]
        else:
            email = None
    else:
        email = None
    
    if email is None:
        return render(
            request,
            "index.html",
            context={
            "session": email,
            "pretty": json.dumps(request.session.get("user"), indent=4),
            },
        )
    else:
        return render(
            request,
            "loggedin.html",
            context={
                "session": email,
                "pretty": json.dumps(request.session.get("user"), indent=4),
            },
        )

After enabling OAuth and registering affinidi as the provider, we have defined 2 key routes to enable Affinidi Login in the sample application.

• login that OAuth library and triggers a redirect to Affinidi Login flow using the credentials provided in the OAuth library.

• callback that parses the ID Token using OAuth library sent by Affinidi Login after successful authentication of the user. At the same time, we started the user session with the uder info extracted from the ID Token.

Summary

sequenceDiagram
    actor User
    participant Django
    participant Affinidi Login
    participant Affinidi Vault
    participant Affinidi Verifier

    User->>Django: My Login
    Django->>Affinidi Login: Authenticate user
    Note over Django, Affinidi Login:  login_challenge
    Affinidi Login->>Affinidi Vault: Verify user identity
    Note over Affinidi Login, Affinidi Vault:  presentationDefinition
    Affinidi Vault->>User: Request user confirmation to share Email VC
    User->>Affinidi Vault: User confirmed consent to share Email VC
    Affinidi Vault->>Affinidi Vault: Generate VP Token from VC
    Affinidi Vault->>Affinidi Login: Send Email VP Token
    Affinidi Login->>Affinidi Verifier: Validate VP Token
    Note over Affinidi Login, Affinidi Verifier:  vp_token, presentation_submission, presentation_definition
    Affinidi Login->>Affinidi Login: Generate idToken
    Affinidi Login->>Django: Send generated idToken from VP
    Django->>User: Provide access to the user

Using the Django framework with AuthLib as the sample application, we have configured it to integrate with Affinidi Login as the Auth provider and parse the idToken sent by the Affinidi Login to confirm the user’s successful authentication using the Affinidi Vault.