Securing Containerized Applications with AWS Cognito

At Vectra AI, I developed a Cognito-integrated user management API using Django REST Framework for secure authentication within containerized applications. This article shares the approach and implementation details.

Why AWS Cognito?

AWS Cognito provides a fully managed user directory service with:

• User registration and sign-in
• Multi-factor authentication
• Social identity provider integration
• Token-based authentication
• Scalability and security

Architecture Overview

Our solution consisted of:

• AWS Cognito User Pool for user management
• Django REST API for business logic
• JWT token validation middleware
• Role-based access control

Setting Up AWS Cognito

First, create a User Pool in AWS Cognito with appropriate settings for password policies, MFA, and custom attributes.

Django REST Framework Integration

We created a custom authentication backend for Django that validates Cognito JWT tokens:

      # authentication.py
      import jwt
      from django.conf import settings
      from rest_framework import authentication, exceptions
      
      class CognitoAuthentication(authentication.BaseAuthentication):
          def authenticate(self, request):
              auth_header = request.headers.get('Authorization')
              if not auth_header:
                  return None
              
              token = auth_header.split(' ')[1]
              
              try:
                  # Verify and decode the JWT token
                  payload = jwt.decode(
                      token,
                      options={"verify_signature": False},
                      algorithms=["RS256"]
                  )
                  
                  # Get or create user based on Cognito user ID
                  user = get_user_from_cognito_id(payload['sub'])
                  
                  return (user, token)
              except jwt.PyJWTError:
                  raise exceptions.AuthenticationFailed('Invalid token')
      

User Management API

Our API provided endpoints for:

• User registration and confirmation
• Authentication and token refresh
• Password reset
• User profile management
• Role and permission assignment

Containerization

The API was containerized using Docker and deployed on AWS ECS, with environment variables for Cognito configuration.

Security Considerations

• Token validation and verification
• HTTPS for all communications
• Proper handling of refresh tokens
• Rate limiting to prevent brute force attacks

Conclusion

Integrating AWS Cognito with Django REST Framework provides a robust, scalable authentication solution for containerized applications. It offloads the complexity of user management while maintaining flexibility for custom business logic.