How do I integrate Ajax with Django applications?

Question

I am new to Django and pretty new to Ajax. I am working on a project where I need to integrate the two. I believe that I understand the principles behind them both, but have

Answer 1

I am writing this because the accepted answer is pretty old, it needs a refresher.

So this is how I would integrate Ajax with Django in 2019 :) And lets take a real example of when we would need Ajax :-

Lets say I have a model with registered usernames and with the help of Ajax I wanna know if a given username exists.

html:

 

      Name: 
       Check            
   

ajax:

$('#username_exists_form').on('submit',function(e){
    e.preventDefault();
    var username = $(this).find('input').val();
    $.get('/exists/',
          {'username': username},   
          function(response){ $('#response_msg').text(response.msg); }
    );
}); 

urls.py:

from django.contrib import admin
from django.urls import path
from . import views

urlpatterns = [
    path('admin/', admin.site.urls),
    path('exists/', views.username_exists, name='exists'),
]

views.py:

def username_exists(request):
    data = {'msg':''}   
    if request.method == 'GET':
        username = request.GET.get('username').lower()
        exists = Usernames.objects.filter(name=username).exists()
        if exists:
            data['msg'] = username + ' already exists.'
        else:
            data['msg'] = username + ' does not exists.'
    return JsonResponse(data)

Also render_to_response which is deprecated and has been replaced by render and from Django 1.7 onwards instead of HttpResponse we use JsonResponse for ajax response. Because it comes with a JSON encoder, so you don’t need to serialize the data before returning the response object but HttpResponse is not deprecated.