Web Development with Django Cookbook- Second Edition

Web Development with Django Cookbook- Second Edition - Second Edition

By : Aidas Bendoraitis

Buy this Book

Web Development with Django Cookbook- Second Edition - Second Edition

By: Aidas Bendoraitis

Buy this Book

Overview of this book

Django is a web framework that was designed to strike a balance between rapid web development and high performance. It has the capacity to handle applications with high levels of user traffic and interaction, and can integrate with massive databases on the backend, constantly collecting and processing data in real time. Through this book, you'll discover that collecting data from different sources and providing it to others in different formats isn't as difficult as you thought. It follows a task-based approach to guide you through all the web development processes using the Django framework. We’ll start by setting up the virtual environment for a Django project and configuring it. Then you’ll learn to write reusable pieces of code for your models and find out how to manage database schema changes using South migrations. After that, we’ll take you through working with forms and views to enter and list data. With practical examples on using templates and JavaScript together, you will discover how to create the best user experience. In the final chapters, you'll be introduced to some programming and debugging tricks and finally, you will be shown how to test and deploy the project to a remote dedicated server. By the end of this book, you will have a good understanding of the new features added to Django 1.8 and be an expert at web development processes.

Web Development with Django Cookbook Second Edition

Credits

About the Author

About the Reviewers

www.PacktPub.com

Preface

Free Chapter

Getting Started with Django 1.8

Introduction

Working with a virtual environment

Creating a project file structure

Handling project dependencies with pip

Making your code compatible with both Python 2.7 and Python 3

Including external dependencies in your project

Configuring settings for development, testing, staging, and production environments

Defining relative paths in the settings

Creating and including local settings

Setting up STATIC_URL dynamically for Subversion users

Setting up STATIC_URL dynamically for Git users

Setting UTF-8 as the default encoding for MySQL configuration

Setting the Subversion ignore property

Creating the Git ignore file

Deleting Python-compiled files

Respecting the import order in Python files

Creating app configuration

Defining overwritable app settings

Database Structure

Introduction

Using model mixins

Creating a model mixin with URL-related methods

Creating a model mixin to handle creation and modification dates

Creating a model mixin to take care of meta tags

Creating a model mixin to handle generic relations

Handling multilingual fields

Using migrations

Switching from South migrations to Django migrations

Changing a foreign key to the many-to-many field

Forms and Views

Introduction

Passing HttpRequest to the form

Utilizing the save method of the form

Uploading images

Creating a form layout with django-crispy-forms

Downloading authorized files

Filtering object lists

Managing paginated lists

Composing class-based views

Generating PDF documents

Implementing a multilingual search with Haystack

Templates and JavaScript

Introduction

Arranging the base.html template

Including JavaScript settings

Using HTML5 data attributes

Opening object details in a modal dialog

Implementing a continuous scroll

Implementing the Like widget

Uploading images by Ajax

Custom Template Filters and Tags

Introduction

Following conventions for your own template filters and tags

Creating a template filter to show how many days have passed since a post was published

Creating a template filter to extract the first media object

Creating a template filter to humanize URLs

Creating a template tag to include a template if it exists

Creating a template tag to load a QuerySet in a template

Creating a template tag to parse content as a template

Creating a template tag to modify request query parameters

Model Administration

Introduction

Customizing columns on the change list page

Creating admin actions

Developing change list filters

Customizing default admin settings

Inserting a map into a change form

Django CMS

Introduction

Creating templates for Django CMS

Structuring the page menu

Converting an app to a CMS app

Attaching your own navigation

Writing your own CMS plugin

Adding new fields to the CMS page

Hierarchical Structures

Introduction

Creating hierarchical categories

Creating a category administration interface with django-mptt-admin

Creating a category administration interface with django-mptt-tree-editor

Rendering categories in a template

Using a single selection field to choose a category in forms

Using a checkbox list to choose multiple categories in forms

Data Import and Export

Introduction

Importing data from a local CSV file

Importing data from a local Excel file

Importing data from an external JSON file

Importing data from an external XML file

Creating filterable RSS feeds

Using Tastypie to create API

Using Django REST framework to create API

Bells and Whistles

Introduction

Using the Django shell

Using database query expressions

Monkey-patching the slugify() function for better internationalization support

Toggling the Debug Toolbar

Using ThreadLocalMiddleware

Caching the method return value

Using Memcached to cache Django views

Using signals to notify administrators about new entries

Checking for missing settings

Testing and Deployment

Introduction

Testing pages with Selenium

Testing views with mock

Testing API created using Django REST framework

Releasing a reusable Django app

Getting detailed error reporting via e-mail

Deploying on Apache with mod_wsgi

Setting up cron jobs for regular tasks

Creating and using the Fabric deployment script

Index

Customer Reviews

5 star

4 star

3 star

2 star

1 star

Including external dependencies in your project

Sometimes, it is better to include external dependencies in your project. This ensures that whenever a developer upgrades third-party modules, all the other developers will receive the upgraded version in the next update from the version control system (Git, Subversion, or others).

Also, it is better to have external dependencies included in your project when the libraries are taken from unofficial sources, that is, somewhere other than Python Package Index (PyPI), or different version control systems.

Getting ready

Start with a virtual environment with a Django project in it.

How to do it…

Execute the following steps one by one:

If you haven't done this already, create an externals directory under your Django project django-myproject directory. Then, create the libs and apps directories under it.
The libs directory is for the Python modules that are required by your project, for example, boto, Requests, Twython, Whoosh, and so on. The apps directory is for third-party Django apps, for example, django-cms, django-haystack, django-storages, and so on.
Tip
I highly recommend that you create the README.txt files in the libs and apps directories, where you mention what each module is for, what the used version or revision is, and where it is taken from.
The directory structure should look something similar to the following:

The next step is to put the external libraries and apps under the Python path so that they are recognized as if they were installed. This can be done by adding the following code in the settings:

# settings.py
# -*- coding: UTF-8 -*-
from __future__ import unicode_literals
import os
import sys

BASE_DIR = os.path.abspath(os.path.join(
    os.path.dirname(__file__), ".."
))

EXTERNAL_LIBS_PATH = os.path.join(
    BASE_DIR, "externals", "libs"
)
EXTERNAL_APPS_PATH = os.path.join(
    BASE_DIR, "externals", "apps"
)
sys.path = ["", EXTERNAL_LIBS_PATH, EXTERNAL_APPS_PATH] + \
    sys.path

How it works…

A module is meant to be under the Python path if you can run Python and import that module. One of the ways to put a module under the Python path is to modify the sys.path variable before importing a module that is in an unusual location. The value of sys.path is a list of directories starting with an empty string for the current directory, followed by the directories in the virtual environment, and finally the globally shared directories of the Python installation. You can see the value of sys.path in the Python shell, as follows:

(myproject_env)$ python
>>> import sys
>>> sys.path

When trying to import a module, Python searches for the module in this list and returns the first result that is found.

Therefore, we first define the BASE_DIR variable, which is the absolute path to one level higher than the settings.py file. Then, we define the EXTERNAL_LIBS_PATH and EXTERNAL_APPS_PATH variables, which are relative to BASE_DIR. Lastly, we modify the sys.path property, adding new paths to the beginning of the list. Note that we also add an empty string as the first path to search, which means that the current directory of any module should always be checked first before checking other Python paths.

Tip

This way of including external libraries doesn't work cross-platform with the Python packages that have C language bindings, for example, lxml. For such dependencies, I would recommend using the pip requirements that were introduced in the Handling project dependencies with pip recipe.

Web Development with Django Cookbook- Second Edition - Second Edition

By : Aidas Bendoraitis

Web Development with Django Cookbook- Second Edition - Second Edition

By: Aidas Bendoraitis

Overview of this book

Related Content you might be interested in

Current Title:

Web Development with Django Cookbook- Second Edition - Second Edition

Including external dependencies in your project

Getting ready

How to do it…

Tip

How it works…

Tip

See also