There was a task to submit form with ajax, with server side validation of course. Obvious solution is to do validation and return json with erros.
I didn't like idea of writing separate view for validation and then inserting errors in form html on client side. Especially since I already had a generic template for django form with errors display.
Task
User will see process like this:
- User clicks 'edit' near article block
- article is replaced with form
- in case there are validation errors - they are shown above the form fields
- in case there are no errors - form is replaced by article html
Solution
Server will return piece of html that will replace part of page with article or form (with errors if needed). Actually this sentence is the most important part of this blog post. Implementation is very simple and straightforward.
Well actually the fact that you can return parts of html from server is also not new idea at all. It's just only now I finally understood that using this technique you can create more complicated things than modal window or tabs.
Implementation
views.py
def edit_new(request, new_id):
new = get_object_or_404(MyModel, pk=new_id)
if request.method == 'POST':
form = NewsForm(request.POST, instance=new)
if form.is_valid():
new = form.save()
return render_to_response('include/new.html', dict(new=new))
else:
form = NewsForm(instance=new)
return render_to_response('include/form.html', dict(form=form, new=new))form.html
This html will replace article block on 'edit' button click. Javascript should be moved to separate file of course.
<script type="text/javascript">
function submitAndLoad(input) {
$.ajax({
url: "{% url edit_new new.id %}",
data: $(input).parent().serialize(), // форма
type: "post",
dataType: "html",
success: function(data) {
$(input).parent().parent().html(data); // article block
}
});
return false;
};
</script>
<form>
{{ form }}
<input type="submit" value="Save" onclick="return submitAndLoad(this);"/>
</form>news_list.html
<script type="text/javascript">
function editNew(id) {
$("#new-" + id).load("{% url edit_new new.id %}");
return false;
}
</script>
<!-- ... -->
<div id="new-{{ new.id }}">
{% include "news/new.html" %}
</div>
<a onclick="return editNew({{ new.id }});" href="#">Edit</a>Code can be cleaned up of course, I just wanted to show the idea.
Update
I'm translating this article almost five years after it was originally written and of course now it seems very childish :) Now we have angular and ajax forms are implemented a little differently. Still this old solution is not all that bad. I'd still replace one thing here - it's better to return json with html from server instead of just html.
Subscribe for the news and updates
This article offers key insights into the ISTQB certification and shares a proven preparation strategy to help candidates succeed.
Tired of boring programming courses where you're forced to read thick textbooks and write code that's never used? Need a platform that makes learning fun and exciting? Then you're in the right place!
In this article we'll review general approach to working with the best kind of projects - the ones with old untested and undocumented spaghetti code and a tight schedule. We'll review anger management techniques, coping mechanisms and some refactoring tips that might come in handy.
There are two most popular web frameworks in Python. There is the Django with lots of intelligent defaults and the Flask micro framework with complete freedom in the choice of modules. Let’s see, what django vs flask is in 2017.
When we use css-sprites it's important to make browser cache them for longest period possible. On other hand, we need to refresh them when they are updated. This is especially visible when all icons are stored in single sprite. When it's outdated - entire site becomes ugly.
It appears that not everyone knows that in python you can create classes dynamically without metaclasses. I'll show an example of how to do it.So we've learned how to use custom QuerySet to chain requests:Article.objects.old().public()Now we need to make it work for related objects:user.articles.old().public()This is done using use_for_related_fields, but it needs a little trick.