Book Image

Django 4 By Example - Fourth Edition

By : Antonio Melé
4.6 (5)
Book Image

Django 4 By Example - Fourth Edition

4.6 (5)
By: Antonio Melé

Overview of this book

Django 4 By Example is the 4th edition of the best-selling franchise that helps you build web apps. This book will walk you through the creation of real-world applications, solving common problems, and implementing best practices using a step-by-step approach. You'll cover a wide range of web app development topics as you build four different apps: A blog application: Create data models, views, and URLs and implement an admin site for your blog. Create sitemaps and RSS feeds and implement a full-text search engine with PostgreSQL. A social website: Implement authentication with Facebook, Twitter, and Google. Create user profiles, image thumbnails, a bookmarklet, and an activity stream. Implement a user follower system and add infinite scroll pagination to your website. An e-commerce application: Build a product catalog, a shopping cart, and asynchronous tasks with Celery and RabbitMQ. Process payments with Stripe and manage payment notifications via webhooks. Build a product recommendation engine with Redis. Create PDF invoices and export orders to CSV. An e-learning platform: Create a content management system to manage polymorphic content. Cache content with Memcached and Redis. Build and consume a RESTful API. Implement a real-time chat using WebSockets with ASGI. Create a production environment using NGINX, uWSGI and Daphne with Docker Compose. This is a practical book that will have you creating web apps quickly.
Table of Contents (20 chapters)
18
Other Books You May Enjoy
19
Index

Enabling a channel layer

Channel layers allow you to communicate between different instances of an application. A channel layer is the transport mechanism that allows multiple consumer instances to communicate with each other and with other parts of Django.

In your chat server, you plan to have multiple instances of the ChatConsumer consumer for the same course chat room. Each student who joins the chat room will instantiate the WebSocket client in their browser, and that will open a connection with an instance of the WebSocket consumer. You need a common channel layer to distribute messages between consumers.

Channels and groups

Channel layers provide two abstractions to manage communications: channels and groups:

  • Channel: You can think of a channel as an inbox where messages can be sent to or as a task queue. Each channel has a name. Messages are sent to a channel by anyone who knows the channel name and then given to consumers listening on that channel.
  • ...