|Stable release||1.10.2 / February 24, 2010|
|Type||Web application framework|
|License||New BSD license|
Zend Framework was conceived in early 2005 while many new frameworks, such as Ruby on Rails and the Spring Framework, were gaining popularity in the web development community. ZF was publicly announced at the first Zend Conference in October 2005.
On July 1, 2007, Zend Framework 1.0 was released.
ZF is a use-at-will framework. There is no single development paradigm or pattern that all Zend Framework users must follow, although ZF does provide components for the MVC, Table Data Gateway, and Row Data Gateway design patterns. Zend Framework provides individual components for many other common requirements in web application development.
Zend Framework also seeks to promote web development best practices in the PHP community; conventions are not as commonly used in ZF as in many other frameworks, rather suggestions are put forth by setting reasonable defaults that can be overridden for each ZF application’s specific requirements.
Zend Framework is licensed under the Open Source Initiative (OSI)-approved New BSD License, and all code contributors must sign a Contributor License Agreement (CLA) based on the Apache Software Foundation’s CLA. The licensing and contribution policies were established to prevent intellectual property issues for commercial ZF users, according to Zend's Andi Gutmans.
Zend Technologies, co-founded by PHP core contributors Andi Gutmans and Zeev Suraski, is the corporate sponsor of Zend Framework. Technology partners include IBM, Google, Microsoft, Adobe Systems, and StrikeIron.
Zend Framework requires PHP 5.2.4 or later since version 1.7.0. Previous versions required PHP 5.1.4 or later, although the ZF Programmer's Reference Guide strongly recommended PHP 5.2.3 or later for security and performance improvements included in these versions of PHP. PHPUnit 3.0 or later is required to run the unit tests shipped with Zend Framework. Many components also require PHP extensions.
Zend Framework features include:
Zend Technologies provide a PHP stack, Zend Server (or Zend Server Community Edition), which is optimized for running Zend Framework applications. Zend Server includes Zend Framework in its OS-native, integrated installers, along with PHP and all required extensions. Zend Server provides improved performance for Zend Framework applications through opcode acceleration and several caching capabilities, and comes with application monitoring and diagnostics out-of-the-box.
Zend Server is not required to run Zend Framework applications and the Zend Framework can be downloaded and installed independently of Zend Server.
For developers who prefer an Integrated Development Environment (IDE) for coding and debugging, Zend Studio, tightly integrated with Zend Framework, provides an MVC view, MVC code generation, code formatter, code assist, and more.
Zend Studio is not free software, whereas the Zend Framework and Zend Server (community edition) are free.
Zend Server may not be compatible with common debugging tools such as Xdebug which is bundled with free PHP IDEs such as Netbeans. For this reason, developers who want to use a completely free PHP stack, including an IDE, should consider other alternatives as well as Zend Server.
Code contributions to Zend Framework are subject to rigorous code, documentation, and test standards. All code must meet ZF’s coding standards and unit tests must reach 80% code coverage before the corresponding code may be moved to the release branch.
On September 22, 2009, Zend Technologies announced that it would be working with technology partners including Microsoft, IBM, Rackspace, Nirvanix, and GoGrid along with the Zend Framework community to develop a common API to cloud application services called the Simple Cloud API. This project is part of Zend Framework and will be hosted on the Zend Framework website, but a separate site called simplecloud.org has been launched to discuss and download the most current versions of the API.
The Simple Cloud API will be included in production releases of Zend Framework after the API has been finalized and the adapters to popular cloud services have reached production quality.