HTML over ther Wire, or HTML over the WebSockets, is a strategy for creating real-time SPAs by creating a WebSockets connection between a client and a server. It allows JavaScript to request actions, its only responsibility is to handle events, and the backend handles the business logic as well as rendering HTML. This means you can create pages without reloading the page, without AJAX, APIs or requests. One technology provides a secure, stable and low-delay connection for real-time web applications.
[[#/img/example-scheme.png][Architecture]]
Let's illustrate with an example. I want to render article number 2.
[[#/img/example-blog.png][Blog example]]
1. A WebSockets connection, a channel, is established between the client and the server.
2. JavaScript sends a text, not a request, via WebSockets to the Server (in our case Django).
3. Django interprets the text and renders the HTML of the article through the template system and the database.
4. Django sends the HTML to JavaScript via the channel and tells it which selector to embed it in.
5. JavaScript draws the received HTML in the indicated selector.
The same process is repeated for each action, such as clicking a button, submitting a form, etc.
Django LiveView is a framework for creating Realtime SPAs using HTML over the Wire technology. It is inspired by Phoenix LiveView and it is built on top of Django Channels.
It allows you to create interactive web applications using only HTML, CSS and Python. JavaScript ONLY is used to capture events, send and receive strings over a WebSockets channel.
Now you can create SPAs without using APIs, without JavaScript, and without learning anything new. If you know Python, you know how to use Django LiveView.
Are you ready to create your first Realtime SPA? Let's go to the [[#/docs/quickstart/][Quickstart]].
* Quickstart
:PROPERTIES:
:ONE: one-custom-default-doc
:CUSTOM_ID: /docs/quickstart/
:TITLE: Quickstart
:DESCRIPTION: Get started with Django LiveView the easy way.
Welcome to the Quickstart guide. Here you will learn how to create your first Realtime SPA using Django LiveView. I assume you have a basic understanding of Django and Python.
All the steps are applied in a [[https://github.com/Django-LiveView/minimal-template][minimalist template]].
** 1. Install Django
Install Django, create a project and an app.
** 2. Install LiveView
Install django-liveview with ~pip~.
#+BEGIN_SRC sh
pip install django-liveview
#+END_SRC
** 3. Modify the configuration
Add ~liveview~ to your installed ~INSTALLED_APPS~.
#+BEGIN_SRC python
INSTALLED_APPS = [
"daphne",
"channels",
"liveview",
]
#+END_SRC
Then indicate in which previously created App you want to implement LiveView.
#+BEGIN_SRC python
LIVEVIEW_APPS = ["website"]
#+END_SRC
** 4. Migration
Execute the migrations so that the LiveView tables are generated.
#+BEGIN_SRC python
python manage.py migrate
#+END_SRC
** 5. ASGI
Modify the ASGI file, ~asgi.py~ to add the LiveView routing. In this example it is assumed that settings.py is inside core, in your case it may be different.
Place where the functions and logic of the business logic are stored. We will start by creating an action to generate a random number and print it.
Create inside your App a folder called ~actions~, here will go all the actions for each page. Now we will create inside the folder a file named ~home.py~.
#+BEGIN_SRC python
# my-app/actions/home.py
from liveview.context_processors import get_global_context
There are several points in the above code to keep in mind.
- ~template~ is the name of the template that will be rendered.
- ~get_context()~ is a function that returns a dictionary with the context of the page.
- ~send_page()~ is the function that will be executed when the page is loaded.
- ~random_number()~ is the function that will be executed when the button is clicked.
** 7. Create the base template
Now we will create the base template, which will be the one that will be rendered when the page is loaded.
Create a folder called ~templates~, or use your template folder, inside your App and inside it create another folder called ~layouts~. Now create a file called ~base.html~.
#+BEGIN_SRC html
{# my-app/templates/layouts/base.html #}
{% load static i18n %}
<!doctype html>{% get_current_language as CURRENT_LANGUAGE %}
As you can see, we have defined a button to launch the action of generating the random number (~button~) and the place where we will print the result (~output-random-number~).
** 9. Create frontend
Now we are going to create the frontend, the part where we will manage the JavaScript events and invoke the actions.
Download [[https://github.com/Django-LiveView/assets/archive/refs/heads/main.zip][assets]] and unzip it in your static folder. You will be left with the following route: ~/static/js/~.
** 10. Create View
We will create the view that will render the page for the first time (like Server Side Rendering). The rest of the times will be rendered dynamically (like Single Page Application).
In a normal Django application we would create a view, ~views.py~, similar to the following:
#+BEGIN_SRC python
# my-app/views.py
from django.shortcuts import render
# Create your views here.
def home(request):
return render(request, "pages/home.html")
#+END_SRC
With LiveView, on the other hand, you will have the following structure.
#+BEGIN_SRC python
# my-app/views.py
from django.shortcuts import render
from .actions.home import get_context as get_home_context
It is important to note that the ~proxy_set_header~ lines are necessary for the WebSocket to work. You can see more about it in [[https://channels.readthedocs.io/en/latest/deploying.html][Channels]].
:DESCRIPTION: Frequently asked questions about Django LiveView.
:END:
** Do I need to know JavaScript to use Django LiveView?
No, you don't need. You can create SPAs without using APIs, without JavaScript, and without learning anything new. If you know Python, you know how to use Django LiveView.
** Can I use JavaScript?
Yes, you can. You can use JavaScript to capture events, send and receive strings over a WebSockets channel.
** Can I use Django's native tools?
Of course. You can still use all of Django's native tools, such as its ORM, forms, plugins, etc.
** Do I need to use React, Vue, Angular or any other frontend framework?
No. All logic, rendering and state is in the backend.
