A simple API with pure Django

In this chapter, we will build an API with pure Django. We will not use Django Rest Framework (Or any other library). To start add some Poll using the admin.

The endpoints and the URLS

Our API will have two endpoints returning data in JSON format.

  • /polls/ GETs list of Poll
  • /polls/<id>/ GETs data of a specific Poll

Connecting urls to the views

Write two place holder view functions and connect them in your urls.py. We will finish polls_list and polls_detail shortly.

# In views.py
def polls_list(request):
    pass

def polls_detail(request, pk):
    pass


# in urls.py
from django.urls import path
from .views import polls_list, polls_detail

urlpatterns = [
    path("polls/", polls_list, name="polls_list"),
    path("polls/<int:pk>/", polls_detail, name="polls_detail")
]

Writing the views

We will now write the polls_list and polls_detail

from django.shortcuts import render, get_object_or_404
from django.http import JsonResponse

from .models import Poll

def polls_list(request):
    MAX_OBJECTS = 20
    polls = Poll.objects.all()[:MAX_OBJECTS]
    data = {"results": list(polls.values("question", "created_by__username", "pub_date"))}
    return JsonResponse(data)


def polls_detail(request, pk):
    poll = get_object_or_404(Poll, pk=pk)
    data = {"results": {
        "question": poll.question,
        "created_by": poll.created_by.username,
        "pub_date": poll.pub_date
    }}
    return JsonResponse(data)

This should be standard Django for you. polls = Poll.objects.all()[:20] gets us upto 20 Poll objects. We get a list of dictionaries using {"results": list(polls.values("question", "created_by__username", "pub_date"))} and return it with a JsonResponse. A JsonResponse is a like HttpResponse with content-type=application/json.

Similarly, polls_detail gets a specific Poll using get_object_or_404(Poll, pk=pk), and returns it wrapped in JsonResponse.

Using the API

You can now access the API using curl, wget, postman, browser or any other API consuming tools. Here us the response with curl.

$ curl http://localhost:8000/polls/

{"results": [{"pk": 1, "question": "What is the weight of an unladen swallow?", "created_by__username": "shabda", "pub_date": "2018-03-12T10:14:19.002Z"}, {"pk": 2, "question": "What do you prefer, Flask or Django?", "created_by__username": "shabda", "pub_date": "2018-03-12T10:15:55.949Z"}, {"pk": 3, "question": "What is your favorite vacation spot?", "created_by__username": "shabda", "pub_date": "2018-03-12T10:16:11.998Z"}]}

You should consider using postman or a similar tool. This is how your API looks in Postman.

_images/postman_polls_detail.png

Why do we need DRF?

(DRF = Django Rest Framework)

We were able to build the API with just Django, without using DRF, so why do we need DRF? Almost always, you will need common tasks with your APIs, such as access control, serialization, rate limiting and more.

DRF provides a well thought out set of base components and convenient hook points for building APIs. We will be using DRF in the rest of the chapters.