PHP

Zend_Lucene is an implementation of the Lucene search engine in PHP5 and is included as part of the Zend Framework from version 1.6. Lucene implements all of the standard search engine query syntaxes (eg. boolean and wildcard searches) and stores its index as files so it doesn't need a database server to run. Lucene can be used if you want to add search functionality to a site but don't want to go down the route of building a querying syntax from scratch.

To get started with Lucene you need to create an index. The following code has the effect of creating a directory on your server that Lucene will use to store and retrieve documents.

$index = Zend_Search_Lucene::create('/data/my-index');

To open the index use the following code.

The first thing you learn about in PHP is probably how to print something. This is usually done with a call to the echo or print, but there is another way to print things by writing content directly to the output buffer. The following code looks like you are writing to a file, but the text will appear in the browser window because we are writing to the php://output output stream.

$fp = fopen("php://output", 'r+');
fputs($fp, "Hello World");

Or another way...

file_put_contents("php://output", "Hello World");

The php://output stream is an encapsulation between PHP and the browser. The stream doesn't really exist, but PHP knows what to do with it.

Going back to basics can be useful, even for the most experienced developers. Different languages act and respond in different ways and knowing exactly how some control structures work can be very useful in the long run.

I remember when coding in VB (some years ago now) and realizing that an if statement didn't work like I had expected it to work. I had expected that as soon as a condition was met the code would execute whatever was in that condition and drop out of the if statement. What was actually happening was that the code for any condition met was being executed. I'm not sure if VB still works like that, but it made me realize that a developer must know these things or they could write a system crippling bug without even realizing it.

PHP if statements have been written with efficiency in mind. If a condition is met then the code in the condition is run and the rest of the if statement is skipped. Take the following simple example:

I had a situation the other day where I had an application in Zend Framework and I wanted to redirect a user to another page. This is fine if you are inside a controller as you can use the _redirect() controller helper, but in this instance I was running the code from inside a plugin and so therefore didn't have direct access to the controller.

The solution is to use the getResponse() method, which is accessible to plugins, and which will retrieve the response object. The response object has a function called setRedirect() that is used to redirect. Any headers that have been issued will be overwritten by this function. The following code can be run inside your zend framework plugins to redirect the user to a different page.

What? Don't worry, I can't say it either. It is officially called the Scope Resolution Operator (but also just a double colon) and is used to reference static properties and functions of a class. It is also used to reference overridden functions of classes.

To reference a constant of a class you do something similar to the following.

class MyClass {
 const CONST_VALUE = 'A constant value';
}
 
echo MyClass::CONST_VALUE;

To call a static function or a parameter you need to include the word static in the function or parameter definition. You can then reference this function through the scope resolution operator.

After setting up your session management in your application using one of the Zend_Auth adapters you might want to allow users to stay logged in. What you need to do is set some configuration options in the Zend_Session object. Zend_Auth uses Zend_Session as an object orientated way of manipulating the $_SESSION variable. Any changes you make to the Zend_Session object will affect the Zend_Auth object, as long as you set these options before the sessions are started.

There are a number of configuration options available, but for the effect I was looking for I only needed to change the ones below. You might not need to set all of these, but it gave me the best cross browser behaviour.

If you followed the tutorial on installing PHPDoc then you are probably wondering how to get started actually writing the documentation. PHPDoc will parse all the files given to it and look for comment blocks, it will then use these blocks to create the documentation for your application. A valid PHPDoc comment block must start with a '/**', have a '*' on every line and finish with '*/'. The comment must appear before the section that is being commented upon and any lines within the comment without a '*' will be ignored by the parser.

To create some sample documentation we will use the following useless class.

Some of you might be surprised that you can print directly to a printer of your choice through PHP. This uses a PECL extension but is only available on Windows. It is possible to print using UNIX systems, but you have to call the ps program using the system function.

To install the printer functions on Windows you need to download the PECL library for Windows, found at pecl4win.php.net. Unzip this file and move the file php_printer.dll to your extensions directory in your PHP directory (usually called ext).

Next, open up your php.ini file and add the following line at the end of the extensions list.

extension=php_printer.dll

Then add the following lines at the bottom of the file. This tells PHP what printer to use as a default. If the printer is locally installed then PHP only needs the name.

PHPDocumentor is a fast and convent way of creating API documentation for your PHP programs and classes. If you are familiar with the world of Java, it works in much the same way as the JavaDoc program, indeed, it is based on this program.

PHPDocumentor can be run in a number of different ways, but I have found that the easiest way is to, again, use PEAR to install everything you need. To install PHPDocumentor using PEAR use the following command.

phpdoc install phpdocumentor

To run PHPDocumentor and see a list of commands just type in the following:

phpdoc -h

To run PHPDocumentor you need to provide a couple of options, these are:

PHPUnit is a powerful unit testing framework written in and for PHP. Rather than testing everything as a whole the idea behind PHPUnit is to test that everything works as it is expected to work before it is integrated into the rest of the program. In this way problems are found earlier rather than later and this makes fixing them a lot easier. With tests written for every small component of the program it is then possible to test the whole thing by running all of the tests at once. It is also possible to automate PHPUnit so that everything about a program is tested before it is built. If any tests fail then the build is stopped.

The best way to install PHPUnit is to use the PEAR installer. To install PHPUnit you first need to add the correct channel so that PEAR can find PHPUnit easily. You do this by typing the following into the command line.