Add new object to list without refreshing with Django & Ajax - django

Question

I'm searching for someone who helps me in a Django project with JS, Ajax and jquery.
I'm trying to create something like adding objects on the django-admin page. I used https://www.pluralsight.com/guides/work-with-ajax-django, and almost everything is working fine but...
On my form, I have multiple choice field with authors, when I pressed the button to add a new author, the object is properly saving in DB, but on the form, I can't see a new object. When I reload the page, the new object is on this multiple choice field.
I thought I should refresh the field to see a new object on the list, but I don't know it's the proper way to meet this goal.
[edit]
models.py
class Author(models.Model):
name = models.CharField(max_length=100)
class Book(models.Model):
book_author = models.ManyToManyField(Author,blank=True,)
...
form.py
class AuthorForm(forms.ModelForm):
class Meta:
model = Author
fields = ['name', ]
widgets = {
'name': forms.TextInput(),
}
views.py
I added class SaveAutor
def author_add_view(request):
form = AuthorForm()
return render(request,
"author/custom_create_author.html",
{"form": form})
class SaveAuthor(View):
template_name = "author/custom_create_author.html"
def get(self, request):
author_form = AuthorForm(request)
return render(request,
self.template_name,
{'form': author_form})
def post(self, request):
#assume authorForm has author_name defined
author_form = AuthorForm(data=request.POST)
if author_form.is_valid():
author = Author() #here is class name or form name?
author.name = author_form.cleaned_data['name']
author.save()
return JsonResponse({'author_id': author.id,
'author_name': author.name})
# error response or whatever you want to return
return JsonResponse({'error': 'author form is not valid'})
I had these views registered in urls.py
urls.py
# add an author
path('author/add/', views.author_add_view,
name='author_add'),
# not sure if I should add as_view() at the end
path('author/new-add/', views.SaveAuthor.as_view(),
name='new_author_add'),
When I try check if page with form is displaying properly using the SaveAuthor class based view I get error 'WSGIRequest' object has no attribute 'get', but when I use the author_add_view I got the template.
custom_create_author.html
$("#author-form").submit(function (e) {
// preventing from page reload and default actions
e.preventDefault();
// serialize the data for sending the form data.
var serializedData = $(this).serialize();
// make POST ajax call
$.ajax({
type: 'POST',
url: "{% url '.' %}", //serializer_ajax_mehit_from_vies
data: serializedData,
success: function (response) {
// on successfull creating object
// 1. clear the form.
$("#author-form").trigger('reset');
// 2. focus to nickname input
$("#id_author_name").focus();
},
error: function (response) {
// alert the error if any error occured
alert(response["responseJSON"]["error"]);
}
})
})
{% load static %}
{% load widget_tweaks %}
{% block content %}
<h4>
My author
</h4>
<form id="author-form">
{% csrf_token %}
<p>{{ form.as_p }}</p>
<button class="btn btn-outline-success" type="submit">save</button>
</form>
<br>
{% endblock %}
Here is another page where I'm trying to connect the book with multiple-choice-field author (it's typical form, but I'm enclosing only the button to pop-up the form, where I can add the new author)
add_book.html js code open pop-up windows to create new author
<script type="text/javascript">
$(function () {
$("#create-author").modalForm({
formURL: "{% url 'author_add' %}"
});
})
</script>
<button id="create-author" class="btn btn-primary" type="button" name="button">
<span class="fa fa-plus"/>
</button>
And on this page, I tried to paste your JS code
<script type="text/javascript">
// assume the add author button has an id of add_author_button
$('#create-author').click(function(event){
event.preventDefault();
// assume the text field has an id of author_name
author_name= $('#author_name').val();
create_post(event, author_name);
}
) //<-------- this closing bracket was missing?
function create_post(event, author_name) {
$.ajax({
url: "{% url '.' %}", // the endpoint I'll precise that in comment
type: "POST", // http method
data: {
author_name: author_name,
csrfmiddlewaretoken: $('[name="csrfmiddlewaretoken"]').val()
},
// handle a successful response - data will be a json object returned from your view method
success: function (data) {
if (data.error === null) {
// assume your author multiple choice select has an id of author_sel
// this will append the new author name to the list and will also
// set the value for this author to be the newly created id so you can
// perform other functions on the author like update and/or delete
$('#author_id').append($('<option/>', {
value: data.author_id,
text: data.author_name,
}));
} else {
// display the error on the page
// and/or write it to the console log
console.log(data.error);
}
},
// handle a non-successful http response
error: function (xhr, errmsg, err) {
// display the error on the page
// and/or write it to the console log
console.log(xhr.status + ": " + xhr.responseText); // provide a bit more info about the error to the console
}
});
}
</script>
One closing bracket was missing, so I added in on the JS script.
I had a problem with the endpoint, when I pass the class-based view SaveAuthor(View) (new_author_add by url name) I got the message: the author form is not valid, but when I used author_add_view (author_add by url name) undefined.

Answer 1

The issue is that while you are using AJAX to submit your new author, the author isn't being added to the author's multiple choice field in the current HTML page. Refreshing the page will retrieve the new value but that also does an entire post/refresh loop. Since you are submitting the post using AJAX, you can return the new author's id and name via a JsonResponse and use jQuery to add it to the author's multiple choice field.
views.py
from MyApp.forms import AuthorForm
from MyApp.models import Author
from django.shortcuts import render
from django.views import View
from django.http.response import JsonResponse
class SaveAuthor(View):
template_name = "author/author.html"
def get(self, request):
author_form = AuthorForm()
return render(request,
self.template_name,
{"form": author_form,
"authors":Author.objects.all()})
def post(self, request):
#assume authorForm has author_name defined
author_form = AuthorForm(data=request.POST)
if author_form.is_valid():
author = Author() #here is class name or form name?
author.name = author_form.cleaned_data['name']
author.save()
return JsonResponse({'author_id': author.id,
'author_name': author.name})
# error response or whatever you want to return
return JsonResponse({'error': 'author form is not valid'})Your AJAX
author.html
<!DOCTYPE html>
{% load static %}
<script src="{% static "jquery-3.4.1.min.js" %}"></script>
{% block content %}
<h4>
My author
</h4>
<select id="author_sel" name="author_sel" size="5" class="selectbox">
{% for author in authors %}
<option value="{{author.id}}">{{author.name|capfirst}}</option>
{% endfor %}
</select>
<form id="author-form">
{% csrf_token %}
<p>{{ form.as_p }}</p>
<input type="button" name="button" class="submit_button" id="add_author_button" value="Save">
</form>
<br>
{% endblock %}
<script type="text/javascript">
// assume the add author button has an id of add_author_button
$('#add_author_button').click(function(event){
event.preventDefault();
// assume the text field has an id of author_name
author_name= $('#id_name').val();
create_post(event, author_name);
}) //<-------- this closing bracket was missing?
function create_post(event, author_name) {
$.ajax({
url: ".", // the endpoint I'll precise that in comment
type: "POST", // http method
data: {
name: author_name,
csrfmiddlewaretoken: $('[name="csrfmiddlewaretoken"]').val()
},
// handle a successful response - data will be a json object returned from your view method
success: function (data) {
if (data.error === undefined) {
// assume your author multiple choice select has an id of author_sel
// this will append the new author name to the list and will also
// set the value for this author to be the newly created id so you can
// perform other functions on the author like update and/or delete
$('#author_sel').append($('<option/>', {
value: data.author_id,
text: data.author_name,
}));
} else {
// display the error on the page
// and/or write it to the console log
console.log(data.error);
}
},
// handle a non-successful http response
error: function (xhr, errmsg, err) {
// display the error on the page
// and/or write it to the console log
console.log(xhr.status + ": " + xhr.responseText); // provide a bit more info about the error to the console
}
});
}
</script>
urls.py
from django.urls import path
from . import views
app_name = 'myapp'
urlpatterns = [
# add an author
path('add/', views.SaveAuthor.as_view(), name='author_add'),
]
forms.py
from django import forms
from MyApp.models import Author
class AuthorForm(forms.ModelForm):
class Meta:
model = Author
fields = ['name', ]
widgets = {
'name': forms.TextInput(),
}
models.py
from django.db import models
# Create your models here.
class Author(models.Model):
name = models.CharField(max_length=100)
This is now a complete working example.