* Home
:PROPERTIES:
:ONE: one-custom-default-home
:CUSTOM_ID: /
:TITLE:
:DESCRIPTION: Framework for creating Realtime SPAs using HTML over the Wire technology.
:END:

** What is Django LiveView?

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.

** What are your superpowers?

- Create SPAs without using APIs.
- Uses Django's template system to render the frontend (Without JavaScript).
- The logic is not split between the backend and the frontend, it all stays in Python.
- You can still use all of Django's native tools, such as its ORM, forms, plugins, etc.
- Everything is asynchronous by default.
- Don't learn anything new. If you know Python, you know how to use Django LiveView.
- All in real time.

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.
:END:

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.

#+BEGIN_SRC python
import os
import django

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "core.settings")
django.setup()

from channels.auth import AuthMiddlewareStack
from django.core.asgi import get_asgi_application
from channels.security.websocket import AllowedHostsOriginValidator
from channels.routing import ProtocolTypeRouter, URLRouter
from django.urls import re_path
from liveview.consumers import LiveViewConsumer


application = ProtocolTypeRouter(
    {
        # Django's ASGI application to handle traditional HTTP requests
        "http": get_asgi_application(),
        # WebSocket handler
        "websocket": AuthMiddlewareStack(
            AllowedHostsOriginValidator(
                URLRouter([re_path(r"^ws/liveview/$", LiveViewConsumer.as_asgi())])
            )
        ),
    }
)
#+END_SRC

** 6. Create your first Action

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
from core import settings
from liveview.utils import (
    get_html,
    update_active_nav,
    enable_lang,
    loading,
)
from channels.db import database_sync_to_async
from django.templatetags.static import static
from django.urls import reverse
from django.utils.translation import gettext as _
from random import randint

template = "pages/home.html"

# Database

# Functions

async def get_context(consumer=None):
    context = get_global_context(consumer=consumer)
    # Update context
    context.update(
        {
            "url": settings.DOMAIN_URL + reverse("home"),
            "title": _("Home") + " | Home",
            "meta": {
                "description": _("Home page of the website"),
                "image": f"{settings.DOMAIN_URL}{static('img/seo/og-image.jpg')}",
            },
            "active_nav": "home",
            "page": template,
        }
    )
    return context


@enable_lang
@loading
async def send_page(consumer, client_data, lang=None):
    # Nav
    await update_active_nav(consumer, "home")
    # Main
    my_context = await get_context(consumer=consumer)
    html = await get_html(template, my_context)
    data = {
        "action": client_data["action"],
        "selector": "#main",
        "html": html,
    }
    data.update(my_context)
    await consumer.send_html(data)

async def random_number(consumer, client_data, lang=None):
    my_context = await get_context(consumer=consumer)
    data = {
        "action": client_data["action"],
        "selector": "#output-random-number",
        "html": randint(0, 10),
    }
    data.update(my_context)
    await consumer.send_html(data)
#+END_SRC

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 %}
<html lang="{{ CURRENT_LANGUAGE }}">
    <head>
        <meta charset="utf-8">
        <title>{{ title }}</title>
        <meta
            name="viewport"
            content="width=device-width, initial-scale=1.0, shrink-to-fit=no"
        >
        <meta
            name="description"
            content="{{ meta.description }}"
        >
        <meta
            property="og:image"
            content="{{ meta.image }}"
        >
	<script type="module" src="{% static 'js/main.js' %}" defer></script>
    </head>
    <body
		data-host="{{ request.get_host }}"
		data-debug="{{ DEBUG }}"
	>
            <section id="loading"></section>
	    <section id="notifications" class="notifications"></section>
	    <section id="no_connection"></section>
	    <div class="container">
		<header id="content-header">
		    {% include 'components/header.html' %}
		</header>
		<main id="main" class="main-container">{% include page %}</main>
		<footer id="content-footer">
		    {% include 'components/footer.html' %}
		</footer>
	    </div>
    </body>
</html>
#+END_SRC

In the future we will define ~main.js~, a minimal JavaScript to connect the events and the WebSockets client.

** 8. Create the page template

We will create the home page template, which will be the one that will be rendered when the page is loaded.

Create a folder called ~pages~ in your template folder and inside it create a file called ~home.html~.

#+BEGIN_SRC html
{# my-app/templates/pages/home.html #}
{% load static %}

<main data-controller="home">
    <p>
	<button data-action="click->home#randomNumber">Random number</button>
    </p>
    <h2 id="output-random-number"></h2>
</main>
#+END_SRC

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

from liveview.utils import get_html

async def home(request):
    return render(request, "layouts/base.html", await get_home_context())
#+END_SRC

** 11. Create URL

Finally, we will create the URL that will render the page.

#+BEGIN_SRC python
# my-app/urls.py
from django.urls import path

from .views import home

urlpatterns = [
    path("", home, name="home"),
]
#+END_SRC

** 12. Run the server

Run the server.

#+BEGIN_SRC sh
python manage.py runserver
#+END_SRC

And open the browser at ~http://localhost:8000/~. You should see the home page with a button that generates a random number.

#+ATTR_HTML: :class block-center
[[#/img/quickstart/minimal-template.webp][Random number]]

* Source code
:PROPERTIES:
:ONE: one-custom-default-doc
:CUSTOM_ID: /docs/source-code/
:TITLE: Source code
:DESCRIPTION: List of all related source code.
:END:

- [[https://github.com/Django-LiveView/liveview][LiveView]]: Source code of the Django framework and app published in pip.
- [[https://github.com/Django-LiveView/docs][Website and Docs]]: All documentation, including this same page.
- Templates
    - [[https://github.com/Django-LiveView/starter-template][Starter]]
    - [[https://github.com/Django-LiveView/minimal-template][Minimal]]
    - [[https://github.com/Django-LiveView/assets][Assets]]
- Demos
    - [[https://github.com/Django-LiveView/demo-snake][Snake]]