Django

Django??is a?free and open-source ,?Python -based?web framework ?that follows the model–template–views (MTV)?architectural pattern .It is maintained by the?Django Software Foundation ?(DSF), an independent organization established in the US as a?501 ?non-profit.

Django's primary goal is to ease the creation of complex, database-driven websites. The framework emphasizes?reusability ?and "pluggability" of components, less code, low coupling, rapid development, and the principle of?don't repeat yourself .[9] ?Python is used throughout, even for settings, files, and data models. Django also provides an optional administrative?create, read, update and delete ?interface that is generated dynamically through?introspection ?and configured via admin models.

Some well-known sites that use Django include?Instagram ,?Mozilla ?Disqus ,Bitbucket ,?Nextdoor and?Clubhouse .

Django was created in the fall of 2003, when the?web programmers ?at the?Lawrence Journal-World ?newspaper,?Adrian Holovaty ?and?Simon Willison , began using Python to build applications.?Jacob Kaplan-Moss ?was hired early in Django's development shortly before Simon Willison's internship ended.[16] ?It was released publicly under a?BSD license ?in July 2005. The framework was named after guitarist?Django Reinhardt .[17] ?Adrian Holovaty is a Romani jazz guitar player and a big fan of Django Reinhardt.[citation needed ]

In June 2008, it was announced that a newly formed?Django Software Foundation ?(DSF) would maintain Django in the future.

Components

Screenshot of the Django admin interface for modifying a user account

Despite having its own nomenclature, such as naming the callable objects generating the?HTTP ?responses "views",[7] ?the core Django framework can be seen as an?MVC ?architecture.[8] ?It consists of an?object-relational mapper ?(ORM) that mediates between?data models ?(defined as Python classes) and a?relational database ?("Model"), a system for processing HTTP requests with a?web templating system ?("View"), and a?regular-expression -based?URL ?dispatcher ("Controller").

Also included in the core framework are:

·???????a lightweight and standalone?web server ?for development and testing

·???????a form serialization and validation system that can translate between?HTML ?forms and values suitable for storage in the database

·???????a template system that utilizes the concept of?inheritance ?borrowed from object-oriented programming

·???????a?caching ?framework that can use any of several cache methods

·???????support for?middleware ?classes that can intervene at various stages of request processing and carry out custom functions

·???????an internal dispatcher system that allows components of an application to communicate events to each other via pre-defined signals

·???????an?internationalization ?system, including translations of Django's own components into a variety of languages

·???????a?serialization ?system that can produce and read?XML ?and/or?JSON ?representations of Django model instances

·???????a system for extending the capabilities of the template engine

·???????an interface to Python's built-in?unit test ?framework

Bundled applications

The main Django distribution also bundles a number of applications in its "contrib" package, including:

·???????an extensible authentication system

·???????the dynamic administrative interface

·???????tools for generating?RSS ?and?Atom ?syndication feeds

·???????a "Sites" framework that allows one Django installation to run multiple websites, each with their own content and applications

·???????tools for generating?Google Sitemaps

·???????built-in mitigation for?cross-site request forgery ,?cross-site scripting ,?SQL injection ,?password cracking ?and other typical web attacks, most of them turned on by default

·???????a framework for creating?GIS ?applications

·???????Django's configuration system allows third party code to be plugged into a regular project, provided that it follows the reusable app?conventions. More than 2500 package?are available to extend the framework's original behavior, providing solutions to issues the original tool didn't tackle: registration, search,?API ?provision and consumption,?CMS , etc.

·???????This extensibility is, however, mitigated by internal components' dependencies. While the Django philosophy implies loose coupling,[23] ?the template filters and tags assume one engine implementation, and both the auth and admin bundled applications require the use of the internal?ORM . None of these filters or bundled apps are mandatory to run a Django project, but reusable apps tend to depend on them, encouraging developers to keep using the official stack in order to benefit fully from the apps ecosystem.

·???????Server arrangements

·???????Django can be run in conjunction with?Apache ,?Nginx ?using?WSGI ,?Gunicorn , or?Cherokee ?using flup (a Python module).[24] [25] ?Django also includes the ability to launch a?FastCGI ?server, enabling use behind any web server which supports FastCGI, such as?Lighttpd ?or?Hiawatha . It is also possible to use other?WSGI -compliant web servers.[26] ?Django officially supports five database backends:?PostgreSQL ,?MySQL ,?MariaDB ,?SQLite , and?Oracle .?Microsoft SQL Server ?can be used with django-mssql while similarly external backends exist for?IBM Db2 ,SQL Anywhere and?Firebird .There is a?fork ?named django-nonrel, which supports?NoSQL ?databases, such as?MongoDB ?and?Google App Engine 's Datastore.

·???????Django may also be run in conjunction with?Jython ?on any?Java EE ?application server such as?GlassFish ?or?JBoss . In this case django-jython must be installed in order to provide?JDBC ?drivers for database connectivity, which also can provide functionality to compile Django in to a .war suitable for deployment.