Phing Guide - Introduction

# Introduction

## What Phing Is

Phing is a project build system based on Apache ant [ant]. You can do anything with Phing that you could do with a traditional build system like Gnu make [gnumake], and Phing's use of simple XML build files and extensible PHP "task" classes make it an easy-to-use and highly flexible build framework.

Because Phing is based on Ant, parts of this manual are also adapted from the ant manual (see [ant]). We are extremely grateful to the folks in the Ant project for creating (and continuing to create) such an inspiring build system model, and for the open-source licensing that makes it possible for us to learn from each other and build increasingly better tools.

## Phing & Binarycloud: History

Phing was originally a subproject of Binarycloud. Binarycloud is a highly engineered application framework, designed for use in enterprise environments. Binarycloud uses XML extensively for storing metadata about a project (configuration, nodes, widgets, site structure, etc.). Because Binarycloud is built for PHP, performing extensive XML processing and transformations on each page request is an unrealistic proposition. Phing is used to "compile" the XML metadata into PHP arrays that can be processed without overhead by PHP scripts.

Of course, XML "compilation" is only one of many ways that Binarycloud uses the Phing build system. The Phing build system makes it possible for you to:

- Build multi language pages from one source tree (see binarycloud documentation and [below in this document]),
- Centralize metadata (e.g. your data model) in one XML file and generate several files from that XML with different XSLT.

It the beginning, Binarycloud used the GNU make system; however, this approach had some drawbacks: The "space-before-tab"-problem in makefiles, the fact that it is only natively available for Unix systems etc. So, the need for a better build system arose. Apache Ant was a logical choice -- do to its use of XML build files and modular design. The problem was that Ant is written in Java, so you need to install a JVM on your computer to use it. Besides the need for yet another interpreter (i.e. besides PHP), there was also legal/ideological conflict in requiring a commercial JVM (there were problems with Ant on JVMs other than Sun's) for an LGPL'd Binarycloud.

So, the development of Phing began. Phing is a build system written in PHP and uses the ideas of Ant. The first release was designed & developed simultaneously, and thus not very sophisticated. This original system was quickly pushed to its limits and the need for a better Phing became a priority. Andreas Anderhold, who was responsible for Phing/r1, designed and wrote much of the Phing/r2 that followed. Phing/r2 became the Phing-1.0 that exists today for PHP4.

The current development of Phing is focused on Phing 2, which has involved a number of bugfixes, functionality enhancements, and most significantly a conversion of the codebase to use new PHP5 features such as abstract classes, interfaces, and try/catch/throw exception handling.

## How Phing Works

Phing uses XML buildfiles that contain a description of the things to do. The buildfile is structured into targets that contain the actual commands to perform (e.g. commands to copy a file, delete a directory, perform a DB query, etc.). So, to use Phing, you would first write your buildfile and then you would run phing, specifying the target in your buildfile that you want to execute.

    % phing -f mybuildfile.xml mytarget

By default Phing will look for a buildfile named build.xml (so you don't have to specify the buildfile name unless it is not build.xml) and if no target is specified Phing will try to execute the default target, as specified in the <project> tag.

## Cool, so how can I help?

Phing is under active development and there are many things to be done. To get involved, you can start by doing the following:

- Read this manual to understand Phing ;-)
- Go to http://phing.tigris.org and subscribe to the "dev" mailing list