In this tutorial, we’ll be covering creating a simple Web API.
Along the way, it will introduce the various components that make up the REST framework and give you a comprehensive understanding of how everything fits together.
Introduction
Serializers are responsible for converting python objects into data types understandable by front-end frameworks and vice versa.
Getting started
Let’s start coding. To get started, let’s create a new project.
django-admin startproject djserializers
cd djserializers
Now create an app
python manage.py startapp todo
We’ll need to app your app to your INSTALLED_APPS.
Open djserializers/settings.py
INSTALLED_APPS = [
...
'rest_framework',
'todo',
]
Creating a model for todo app
Let’s create a model for out todo app by creating a simple Todos model that is used to store todos.
Open todo/models.py
from django.db import models
# Create your models here.
class Todos(models.Model):
created = models.DateTimeField(auto_now_add=True)
title = models.CharField(max_length=100, blank=True, default='')
content = models.TextField()
class Meta:
ordering = ['created']
We’ll also create an migration for our todo model, and sync the database.
python manage.py makemigrations snippets
python manage.py migrate
Creating a Serializer class
Web API is to provide a way of serializing and deserializing the todo instances into representations such as JSON
Create a file in the todo folder named serializers.py and add the following.
from rest_framework import serializers
from .models import Todos
class TodoSerializer(serializers.Serializer):
id = serializers.IntegerField(read_only=True)
title = serializers.CharField(required=False, allow_black=True, max_length=100)
content = serializers.CharField(style={'base_template': 'textarea.html'})
def create(self, validated_data):
"""
Create and return a new `Todos` instance, given the validated data.
"""
return Todos.objects.create(**validated_data)
def update(self, instance, validated_data):
"""
Update and return an existing `Todos` instance, given the validated data.
"""
instance.title = validated_data.get('title', instance.title)
instance.content = validated_data.get('content', instance.content)
instance.save()
return instance
A serializer class is very similar to a Django Form class, and includes similar validation flags on the various fields, such as required, max_length and default.
Writing regular Django views
from django.shortcuts import render
# Create your views here.
from django.http import HttpResponse, JsonResponse
from django.views.decorators.csrf import csrf_exempt
from rest_framework.parsers import JSONParser
from .models import Todos
from .serializers import TodoSerializer
@csrf_exempt
def todos_list(request):
if request.method == 'GET':
todo = Todos.objects.all()
serializer = TodoSerializer(todo, many=True)
return JsonResponse(serializer.data, safe=False)
elif request.method == 'POST':
data = JSONParser().parse(request)
serializer = TodoSerializer(data=data)
if serializer.is_valid():
serializer.save()
return JsonResponse(serializer.data, status=201)
return JsonResponse(serializer.errors, status=400)
@csrf_exempt
def todo_detail(request, id):
try:
todo = Todos.objects.get(pk=id)
except Todos.DoesNotExist:
return HttpResponse(status=404)
if request.method == 'GET':
serializer = TodoSerializer(todo)
return JsonResponse(serializer.data)
elif request.method == 'PUT':
data = JSONParser().parse(request)
serializer = TodoSerializer(todo, data=data)
if serializer.is_valid():
serializer.save()
return JsonResponse(serializer.data)
return JsonResponse(serializer.errors, status=400)
elif request.method == 'DELETE':
todo.delete()
return HttpResponse(status=204)
Then we need to bind these views. Create a file urls.py in todo folder
from django.urls import path
from todo import views
urlpatterns = [
path('todo/', views.todos_list),
path('todo/<int:id>', views.todo_detail),
]
Now bind app urls.py to site urls.py
from django.urls import path, include
urlpatterns = [
path('admin/', admin.site.urls),
path('',include('todo.urls')),
]
Testing Web API
Startup Django’s development server.
python manage.py runserver
Validating models...
System check identified no issues (0 silenced).
October 07, 2020 - 07:22:22
Django version 3.1.2, using settings 'djserializers.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
Finally, we can get a list of all of the todos:
curl http://127.0.0.1:8000/todo/
[
{
"id": 1,
"title": "Homework",
"content": "Do Homework"
}
{
"id": 2,
"title": "Food",
"content": "Do shoping"
}
]
Or we can get a particular todo by referencing its id:
curl http://127.0.0.1:8000/todo/1
[
{
"id": 1,
"title": "Homework",
"content": "Do Homework"
}
]
Wrapping Up
We’re doing okay so far,we’ve got a serialization API that feels pretty similar to Django’s Forms API, and some regular Django views.
For more details Django REST