Implement MojoAuth OIDC (Python / Flask)

This expert AI assistant guide walks you through integrating passwordless authentication into a Python Flask application using MojoAuth's Hosted Login Page as an OIDC identity provider. MojoAuth handles all authentication methods (Magic Links, Email OTP, SMS OTP, Social Login, Passkeys) through its hosted page.

1. Prerequisites

An existing Python Flask application.
Python 3.8+ installed.
An active MojoAuth account.
MojoAuth OIDC Setup Guide
Required libraries: authlib, flask, python-dotenv.

2. Implementation Steps

Step 1: Configure Application in MojoAuth

Log in to the MojoAuth Dashboard.
Note your MojoAuth Domain (e.g., your-app.mojoauth.com).
Configure the Redirect URI (e.g., http://localhost:5000/auth/callback).
Retrieve Client ID and Client Secret.
Enable your preferred authentication methods.

Step 2: Modify the Existing Flask Project

Substep 2.1: Install Dependencies

pip install authlib flask python-dotenv requests

Substep 2.2: Configure Environment Variables

Create a .env file in the project root:

MOJOAUTH_DOMAIN=your-app.mojoauth.com
MOJOAUTH_CLIENT_ID=your_client_id
MOJOAUTH_CLIENT_SECRET=your_client_secret
MOJOAUTH_REDIRECT_URI=http://localhost:5000/auth/callback
FLASK_SECRET_KEY=a_strong_random_secret

Substep 2.3: Configure OIDC Client

Create a dedicated utility file for OIDC configuration (e.g., lib/oidc.py):

# lib/oidc.py
import os
from authlib.integrations.flask_client import OAuth

oauth = OAuth()

def init_oauth(app):
    """Initialize the OAuth registry with the MojoAuth provider."""
    oauth.init_app(app)
    oauth.register(
        name='mojoauth',
        client_id=os.getenv('MOJOAUTH_CLIENT_ID'),
        client_secret=os.getenv('MOJOAUTH_CLIENT_SECRET'),
        server_metadata_url=f"https://{os.getenv('MOJOAUTH_DOMAIN')}/.well-known/openid-configuration",
        client_kwargs={
            'scope': 'openid profile email',
        },
    )

Substep 2.4: Update Login Page/UI

Since MojoAuth handles all authentication on its Hosted Login Page, your login page only needs a "Sign In" link:

<!-- templates/login.html -->
<!DOCTYPE html>
<html>
<head><title>Sign In</title></head>
<body>
  <div class="login-container">
    <h1>Welcome</h1>
    <p>Sign in with your preferred method — passwordless, social login, or passkeys.</p>

    {% if error %}
      <p style="color: red;">{{ error }}</p>
    {% endif %}

    <a href="/auth/login" class="sign-in-button">Sign In with MojoAuth</a>

    <p class="powered-by">Powered by MojoAuth — Passwordless Authentication</p>
  </div>
</body>
</html>

Substep 2.5: Update Backend Logic

Main Application Setup (app.py):

# app.py
import os
import secrets
from dotenv import load_dotenv
from flask import Flask, redirect, url_for, session, render_template, request
from lib.oidc import oauth, init_oauth

load_dotenv()

app = Flask(__name__)
app.secret_key = os.getenv('FLASK_SECRET_KEY')

# Initialize OAuth
init_oauth(app)


@app.route('/login')
def login_page():
    error = request.args.get('error')
    return render_template('login.html', error=error)


@app.route('/auth/login')
def login():
    # Generate a random state for CSRF protection
    state = secrets.token_urlsafe(16)
    session['oidc_state'] = state

    redirect_uri = os.getenv('MOJOAUTH_REDIRECT_URI')
    return oauth.mojoauth.authorize_redirect(
        redirect_uri,
        state=state,
    )


@app.route('/auth/callback')
def callback():
    try:
        # Verify state
        stored_state = session.pop('oidc_state', None)
        received_state = request.args.get('state')

        if stored_state != received_state:
            return redirect('/login?error=state_mismatch')

        token = oauth.mojoauth.authorize_access_token()
        userinfo = token.get('userinfo')

        if not userinfo:
            userinfo = oauth.mojoauth.userinfo()

        # TODO: Create a session for the user based on `userinfo`
        session['user'] = dict(userinfo)
        print('Authenticated User:', userinfo)

        # Redirect to the dashboard or intended page
        return redirect('/dashboard')
    except Exception as e:
        print(f'OIDC Callback Error: {e}')
        return redirect('/login?error=auth_failed')


@app.route('/dashboard')
def dashboard():
    user = session.get('user')
    if not user:
        return redirect('/login')
    return f"<h1>Dashboard</h1><pre>{user}</pre><a href='/auth/logout'>Logout</a>"


@app.route('/auth/logout')
def logout():
    session.clear()
    return redirect('/login')


if __name__ == '__main__':
    app.run(debug=True, port=5000)

Step 3: Test the Implementation

Start your application: python app.py.
Navigate to http://localhost:5000/login.
Click "Sign In with MojoAuth".
You should be redirected to the MojoAuth Hosted Login Page.
Authenticate using any available method.
After successful authentication, you should be redirected back to /auth/callback and then to /dashboard.

3. Additional Considerations

Error Handling: Enhance the callback route to handle specific OIDC errors gracefully.
Styling: Adapt the example HTML/CSS to match your application's design system.
Security: Use a production-grade session backend (e.g., Redis via flask-session) and serve over HTTPS.
Environment Variables: Never commit .env to source control. Use secrets management in production.

4. Support

MojoAuth Documentation: mojoauth.com/docs
Check application logs: Use server-side logging to debug OIDC flow issues.
Library Documentation: Refer to the Authlib documentation for advanced configuration.

oidc-hosted-page-python