Structure your Python Module

Your module's main directory example is a Django app generated with the startapp command.

In the example directory, you perform multiple functions.  For example, you can:

• create a urls.py file to expose endpoints

• create a viewsets.py file to leverage Django Rest Framework.

In the following scenario, we’re going to expose a /qrcode endpoint for our module that takes text and returns a base64 image.

1. Create a viewsets.py file with the following contents.

   from drf_spectacular.utils import extend_schema, OpenApiParameter, OpenApiExample
   from rest_framework.views import APIView
   from rest_framework.response import Response
   from rest_framework import status, serializers
   import io
   import qrcode
   import base64
   
   class TextLikeSerializer(serializers.Serializer):
       text = serializers.CharField()
   
   class QRLikeSerializer(serializers.Serializer):
       qrcode = serializers.CharField()
   
   class QRCodeView(APIView):
       @extend_schema(request=TextLikeSerializer, responses=QRLikeSerializer)
       def post(self, request, *args, **kwargs):
           """
           This function takes text as input and returns Qrcode Image converted into base64 string.
           """
           qr = qrcode.QRCode(
               version=1,
               error_correction=qrcode.constants.ERROR_CORRECT_H,
               box_size=4,
               border=4,
           )
   
           qr.add_data(request.data["text"])
           qr.make(fit=True)
           img = qr.make_image()
   
           buffered = io.BytesIO()
           img.save(buffered, format="PNG")
           img_str = base64.b64encode(buffered.getvalue()).decode("utf-8")
           return Response({"qrcode": img_str}, status=status.HTTP_200_OK)

2. Create a urls.py file that registers the endpoint in the router.

   from django.urls import path, include
   from rest_framework import routers
   
   from .viewsets import QRCodeView
   
   router = routers.DefaultRouter()
   urlpatterns = [
       path("", include(router.urls)),
       path("qrcode/", QRCodeView.as_view()),
   ]

3. Install the module again.

   cb add django-example
   python manage.py runserver # restart if already running/
   

4. Visit localhost:8000 and you should see this new endpoint.