Implementing SMS Authentication in Django REST Framework (DRF) in 5 Minutes (Zero Paperwork)

Have you ever given up on adding SMS authentication to your side project?

If you're a developer, you've probably experienced the frustration of trying to implement mobile SMS authentication for a sign-up process. Traditional SMS API providers and telecom companies usually demand a mountain of paperwork: business registration certificates, proof of use, and pre-registration of sender numbers.

"But I just want to add a simple login to my MVP or toy project!" 🤔

To solve this massive headache, today we will look at how to implement SMS authentication in Django REST Framework (DRF) using EasyAuth—a developer-centric API that requires absolutely zero paperwork and takes less than 5 minutes to integrate.

The DRF SMS Authentication Workflow

The SMS OTP (One-Time Password) process is surprisingly straightforward. You only need to expose two API endpoints to your frontend:

1. POST /send: Triggers the SMS with a 6-digit verification code to the user's phone.
2. POST /verify: Verifies the code entered by the user.

1. Prerequisites

First, install the necessary packages for your Django project.

pip install django djangorestframework requests

Sign up for EasyAuth to get your API key, and store it safely in your settings.py.

# settings.py
EASYAUTH_API_KEY = 'your_easyauth_api_key_here'
EASYAUTH_URL = 'https://api.easyauth.co.kr'

2. Implementing Send and Verify APIs (views.py)

We will use DRF's APIView and the Python requests library to wrap the EasyAuth API.

import requests
from django.conf import settings
from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework import status

class SendSMSOTPView(APIView):
    """API to Send SMS Verification Code"""
    def post(self, request):
        phone = request.data.get('phone')
        if not phone:
            return Response({'error': 'Phone number is required.'}, status=status.HTTP_400_BAD_REQUEST)

        # Call EasyAuth /send endpoint
        headers = {'Authorization': f'Bearer {settings.EASYAUTH_API_KEY}'}
        response = requests.post(
            f'{settings.EASYAUTH_URL}/send',
            headers=headers,
            json={'phone': phone}
        )

        if response.status_code == 200:
            return Response({'message': 'Verification code sent successfully.'}, status=status.HTTP_200_OK)
        
        return Response({'error': 'Failed to send verification code.'}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)


class VerifySMSOTPView(APIView):
    """API to Verify SMS Code"""
    def post(self, request):
        phone = request.data.get('phone')
        code = request.data.get('code')
        
        if not phone or not code:
            return Response({'error': 'Both phone number and code are required.'}, status=status.HTTP_400_BAD_REQUEST)

        # Call EasyAuth /verify endpoint
        headers = {'Authorization': f'Bearer {settings.EASYAUTH_API_KEY}'}
        response = requests.post(
            f'{settings.EASYAUTH_URL}/verify',
            headers=headers,
            json={'phone': phone, 'code': code}
        )

        if response.status_code == 200:
            # TODO: Handle successful verification (e.g., login the user, issue JWT token)
            return Response({'message': 'Verification successful.'}, status=status.HTTP_200_OK)
            
        return Response({'error': 'Invalid or expired verification code.'}, status=status.HTTP_400_BAD_REQUEST)

3. URL Routing (urls.py)

Now, route the views in your URL configuration.

from django.urls import path
from .views import SendSMSOTPView, VerifySMSOTPView

urlpatterns = [
    path('auth/sms/send/', SendSMSOTPView.as_view(), name='sms-send'),
    path('auth/sms/verify/', VerifySMSOTPView.as_view(), name='sms-verify'),
]

Pro Tips & Security Best Practices 💡

• Rate Limiting: To prevent malicious users from abusing the SMS endpoint and incurring costs, strongly consider applying DRF's built-in AnonRateThrottle.
• Expiration Management: EasyAuth handles standard OTP expiration natively, meaning you don't have to set up your own Redis instance just to track OTP TTL (Time To Live). This saves significant server resources.

Conclusion

With just a few lines of DRF code and the EasyAuth API, we've entirely solved the headache of mobile SMS verification. No more waiting days for telecom approvals or wrestling with complex Redis setups.

Are you a solo developer, freelancer, or building a startup MVP?
Try EasyAuth today. You can start in literally 5 minutes with zero business registration required and an auto-assigned sender number. Plus, at 15~25 KRW per message, it's significantly cheaper than traditional providers. Sign up now and get 10 free credits to test your API! 🚀