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OK. I've just spent two hours trying to sort this problem out so I thought I would pass on the info.

I installed Apache and PHP and they worked fine, but every time I tried to run any MySQL commands through PHP the Apache server would simply crash.

After looking at the Event Viewer the problem appears to be from a file called php5ts.dll, but trying to do anything with this file will lead you down a blank alley.

What is happening is to do with a file called libmysql.dll. This file can be found in your PHP directory, but it is also to be found in your MySQL install directory. This is where the problem lies. When Apache asks for the libmysql.dll file it will receive the one in the MySQL directory because this included in the Windows PATH variable. This version of the libmysql.dll file causes Apache to crash.

PHPUnit is a unit testing framework, written in PHP, and which is used to test PHP code. You can integrate the testing that PHPUnit does into Phing. You might want to use Phing to create a nightly build that contains the latest version of your program. The last thing you want is Phing to create a nightly build that is riddled with errors.

The way around this is to use PHPUnit to test our code whilst we are running Phing. If any tests fail then Phing will not finish the build.

Create a target at the top of your build.xml file and make sure it is run first. Then add the following code to the target, This will use PHPUnit to test your code.

Building your projects into directories is nice, but distributing these projects is difficult if you have to build the compressed files yourself. Phing has the ability to create zip and tar files using simple commands.

The most convenient way of using the tar and zip commands is by using a fileset. But rather than use the fileset that was used to copy the files into the build directory it is best to create a separate fileset that is used to compress the contents of the build directory.

After following the last post on deleting files and directories in Phing you might now be wondering if you can create things as well. The answer is yes.

To create a directory with Phing you need to use the mkdir element. The dir attribute is used to give the name of the directory to be created. The following example will create a directory called myProject_build in the current working directory (ie. where you are running phing from).

<mkdir dir="myProject_build" />

That is about as complicated as the mkdir element gets, although you can also pass a parameter to the dir attribute.

Although using Phing is mainly about copying files, you might also need to delete directories and files using the delete element. Remember that the default behavior of copy command copies files only if the source files are different from the destination files. A prudent approach might be to delete the build directory and then recreate it, ready for Phing to copy files into.

To delete a directory you need to use the dir attribute of the delete element, the delete element also accepts the file attribute to delete specific files. The following target will delete the directory myProject_build.

<target name="prepare">
<delete dir="myProject_build" />
</target>

The delete element can also accept a fileset element, which will delete multiple files. the following code will delete any php file from the myProject_build folder and from a sub folder called app.

The FilterChain element is where the power of Phing really comes into its own. This element will allow you to change the contents of the files of a fileset. This can range from a simple stripping of comments, to replacing values and numerous other filters.

One of the simplest thing that can be done with filterset is to strip all comments from the files in question. Take the following PHP file with two comments.

<?php
/**
 *
 * This is a comment
 *
 *
 **/
echo 'Hello World!';
 
// another comment.

These comments can be stripped out of the file by using the stripphpcomments element. This is added to the copy element in the following way.

Aside from assigning and using your own properties Phing also comes with a set of built in properties that can be used to find out all sorts of information regarding the system that Phing is run on.

As an example, let's say you wanted to found out the operating system that phing is being run on. In this case you would use the variable host.os, which on a Windows XP system would print out WINNT.

There are a lot of different properties available, so I have included the table from the phing website at the bottom of this post as a reference. However, there is one special variable called env that needs further explanation. The env variable references any environment variables that have been set. For example, if you set an environment variable using the following shell command (on UNIX based systems only).

export TESTVAR=mytestvar

You can now reference this in your build.xml file by using the following.

Phing allows you to set up certain parameters that can be used throughout the rest of the script. These might be used to define a non standard build directory, or to store database connection details that can be written to the connection file during the build.

Properties are defined using the property element, which you should place at the top of your build.xml file in order to make it easy for other developers to see what is going on. The following example defines a property and the uses the main target to print the property out.

<?xml version="1.0"?>
<!-- build xml -->
<project name="myProject" default="main">
 <property name="property1" value="value1" />
 
 <target name="main">
  <echo>property1: ${property1}</echo>
 </target>
</project>

Running this build.xml file will product the following result.

When a project gets complicated then so to can the build.xml file associated with it. You might find it necessary to have multiple different filesets, each of which do something different, but all of which have the same core files that they use. Multiple filesets are useful if you want to create a version of your project with all of the testing files in place so that it can be tested by external developers.

Creating multiple filesets can create problems, one of which is maintenance. Confusion can also occur even if you have a single large fileset where lots of different rules for including and excluding files are defined.

This is where the patternset element comes in. You can create a set of reusable file lists that can be used by more than one fileset, but which also makes maintenance a little easier.

The following snippet shows two patternset elements that show include files and exclude files.

One issue, especially when creating AJAX applications, is that the browser can cache the contents of the page so that when a similar request is made the same content is presented.

To force the browser to present the content you want it to without caching you can add the following headers to your page.

header("HTTP/1.1 202 Accepted");
header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header("Cache-Control: no-store, no-cache, proxy-revalidate, must-revalidate");
header("Cache-Control: post-check=0, pre-check=0", false);
header("Cache-Control: max-age=10000000, s-maxage=1000000");
header("Pragma: no-cache");

Remember to put this before you print out any content as you will get some nice looking errors otherwise.

Also, I wouldn't put this on every page on the site as it can create an overhead that just isn't needed.