Here’s something in the making, a PHP extension which caches MySQL queries irrespective of the extension being used. It’s a plugin for mysqlnd, the native MySQL driver for PHP called  mysqlnd_qc. This currently requires PHP 5.3.3-dev which is still in development.

The extension allows caching buffered queries through mysql_query and mysqli_query. It allows cache-invalidation though TTL or a user defined callback. This extension is still in the protoype stage right now and will evolve as the project progresses.

The Query Cache is implemented as a PHP extension. It is written in C and operates “under the hood” of PHP. During the start up of the PHP interpreter it gets registered as a mysqlnd plugin to replaces selected mysqlnd methods.

At PHP run time it proxies queries send from mysqlnd/PHP to the MySQL server. If a query string starts with the SQL hint (/*qc=on*/) to enable caching of it and the query is not cached (Cache miss), the query cache plugin will record the raw wire protocol data send from MySQL to PHP to answer the query. The query cache records the wire protocol data in its cache medium and replays it, if still valid, on a cache hit.

Note that the query cache does not hold decoded result sets consisting of zvals (C struct representing a PHP variable). It stores the raw wire data of the MySQL client server protocol. In case of a cache hits, mysqlnd still needs to decode the cached raw wire data into PHP variables before passing the result to the user space. This approach has one major advantage: simplicity.

You can get more information and installation instructions over at the MySQLND Query Cache Project page at Mysql Forge.

Check out this slide which gives you more information about this extension:

1. Introduction

2. The Architecture of Zend Framework Applications

3. The Model

4. Installing The Zend Framework

5. A Not So Simple Hello World Tutorial

6. Standardise The Bootstrap Class With Zend_Application

7. Handling Application Errors Gracefully

8. Developing A Blogging Application

9. Implementing The Domain Model: Entries and Authors

10. Setting The Design With Zend_View, Zend_Layout, HTML 5 and Yahoo! User Interface Library

A. Creating A Local Domain Using Apache Virtual Hosts

B. Performance Optimisation For Zend Framework Applications

C. Copyright Information

If you’re already working on the Zend Framework, take a look at the section on Performance optimizations for apps built on the Zend Framework, which has some useful tips.

This project is still quite new and their documentation is down to the bare minimum. They do have the required documentation for you you’ll need to get your hands dirty with FRAPI. First you’ll have to download the sources and set it up on your own. One you’ve downloaded the files and setup the directory permissions, you’ll also have to make the Apache Virtual host settings to get FRAPI to start working.

FRAPI has the following requirements for it to run:

• PHP 5.2.2 or later
• APC: Required for caching of actions, errors, etc.
• HTTP: (http://pecl.php.net/pecl_http
• PEAR: (http://pear.php.net)
• PEAR::HTTP_Request2: This could be replaced by pecl_http however it is used in the bundled ArmChair package which is used to access CouchDB (http://pear.php.net/HTTP_Request2)

Some of the advantages I see after playing around with FRAPI is that it auto-generates the code skeleton for you to work on so you just have to go fill in the blanks to create your service. You also don’t have to worry about transfoming the your data into different formats, FRAPI supports JSON, XML, PHP, and plain text natively. This enables you to make your webservices cross-platform and even power mobile apps. You also don’t have to tweak around with code which handles http requests and responses while creating your webservices.

For more information on this project, head over to their site  getfrapi.com or their project page on github.

What if you could actually check the server load in your PHP application? Would you think about checking the server load before doing some heavy computational task or database accesses? There’s function in PHP which will allow you to check the load averages on a server.

The sys_getloadavg() in PHP gives you the load averages for your server. You can use this to check the load on your server before processing a request.

$serverload = sys_getloadavg();
print_r($serverload);

The code above gives the output:

Array
(
    [0] => 1.07
    [1] => 0.89
    [2] => 1
)

The output from the code shows the system load averages where [0] is the load averages for the past 1 minute, [1] is for the past 5 minutes and [2] is for the past 15 minutes.

On an ideal server, the load averages on the server shouldn’t go above 3. A load average of more than 15 would mean that the server is already running much lower than normal, and you may not want to add more load to this.

You can use this output to decide whether to serve a process intensive page depending on the server load. Here’s a pseudo-code on how you’d do something like this:

$serverload = sys_getloadavg();
if ($serverload[0]<10)
  {
    // process loads of data now
    some_big_process();
  } else
     {   // Send a 503 header stating that the server is overloaded.
         header('HTTP/1.1 503 Too busy, try again later');
         die('The server is busy at present and cannot process your request.');
      }

You can also run the application in such a way that you can wait till the load on the server decreases to run your process. This is useful if you are running a cron for processing data:

set_time_limit(0);
//set time limit to 0, so PHP's max execution time doesn't interfere with the processing script
$serverload = sys_getloadavg();
//Check load and see if it's low enough to start processing
while ($serverload[0]>5)
{  //Wait for 1 minute to check load again
    sleep(60);
}
// out of the loop - so let's do some processing now!
some_big_process();

To ensure that the script doesn’t run endlessly on a permanently overloaded server, time check in the while loop to auto-end the script it the server load remains high for a certain amount of time.

More reading:
Load & Load Averages on Wikipedia
PHP function – sys_getloadavg

Harsha’s put up a tenative list of talks for this month’s event:

• Developing Facebook Application using PHP by Sriram Kumar
• Job Queues by Abhinav Lal
• Zend ACL Component - Bare_Acl by Sudheer Satyanarayana

Here’s the link to this month’s meetup event – www.meetup.com/Bangalore-PHP-Users/calendar/13135127. We’ll keep that page updated with the latest details about the event. If you are planning on coming for this, join our Meetup group and RSVP ‘YES’ to the event.

As always – Please forward that link to your friends who you think would be interested in our group as well.

Webinar – PHP Development Best Practices: The Untold Story of Geekville
January 19, 2010 – 9:00 am PST – your computer via webex

Have you ever wondered how you could advance your PHP development? Have you considered using an Integrated Development Environment (IDE), an Issue Tracker or a Version Control tool, but were concerned about how complex it might be? Taking PHP development to the next level may be easier than you think.  Attend this webinar, hosted by Atlassian and Zend More Information/Registration

Webinar – Troubleshooting PHP Issues: Best (and Worst) Techniques
January 28, 2010 – 8:00 am PST – your computer via webex

Understanding what’s causing your PHP application to be slow or just break is often time-consuming, and almost always frustrating. Join this information-packed webinar, delivered by a senior Zend PHP consultant, to learn what techniques PHP professionals use for pinpointing PHP issues in development, testing and production. More Information/Registration

In this book, PHP 5′s co-creator and two leading PHP developers show you how to make the most of PHP 5′s industrial-strength enhancements in any project—no matter how large or complex. Their unique insights and realistic examples illuminate PHP 5′s new object model, powerful design patterns, improved XML Web services support, and much more. Whether you’re creating web applications, extensions, packages, or shell scripts—or migrating PHP 4 code—here are high-powered solutions you won’t find anywhere else.

Review PHP’s syntax and master its object-oriented capabilities—from properties and methods to polymorphism, interfaces, and reflection

• Master the four most important design patterns for PHP development
• Write powerful web applications: handle input, cookies, session extension, and more
• Integrate with MySQL, SQLite, and other database engines
• Provide efficient error handling that’s transparent to your users
• Leverage PHP 5′s improved XML support—including parsing, XSLT conversions, and more
• Build XML-based web services with XML-RPC and SOAP
• Make the most of PEAR: work with the repository, use key packages, and create your own
• Upgrade PHP 4 code to PHP 5—compatibility issues, techniques, and practical workarounds
• Improve script performance: tips and tools for PHP optimization
• Use PHP extensions to handle files/streams, regular expressions, dates/times, and graphics
• Create original extensions and shell scripts

If you’re a software developer new to PHP, you’ll leap quickly into PHP and its new object-oriented capabilities. If you’re an experienced PHP programmer, you already recognize PHP’s convenience and simplicity. Now, discover all of its extraordinary power!

Free Ebook download: Download PHP 5 Power Programming (PDF)
If you like this book and would like to order the Print book, check out Amazon’s deals on PHP 5 Power Programming.

Practical PHP Testing is an ebook which is a compilation of  articles from Giorgio Sironi’s blog on Practical PHP testing.

This book takes you though the basics of PHPUnit – how to install it and start writing simple tests using PHP Unit. Here are some of what this ebook covers:

• bonus chapter on TDD theory;
• a case study on testing a php function;
• working code samples, some of whom were originally kept on pastebin.com;
• sets of TDD exercises at the end of each chapter;
• glossary that substitutes external links to wiki and other posts, to not interrupt your reading with terms lookup.

More information and download link is available here.

Here are some of the reports that XHProf provides:

• Flat profile (screenshot)
• Hierarchical profile (Parent/Child View) (screenshot)
• Diff Reports : The “flat” view (sample screenshot) & “hierarchical” (or parent/child) diff view of a function (sample screenshot).
• Callgraph View (sample screenshot)
• Memory Profile : XHProf’s memory profile mode helps track functions that allocate lots of memory.

If you are looking for an article which gives you details on how to install this extension in Ubuntu and a quick runthrough of how to use this, Lorenzo Alberton has an excellent article on this at Profiling with XHProf. There’s also a good background article on XHProf and why Facebook developed this extension over at Facebook.

Links:
XHProf Documentation
XHProf on PECL
Profiling with XHProf

Image Credit: from Crestock Photos

Igbinary is a  replacement for the standard PHP serializer. While the PHP serializer uses a texual format to represent the data in the serialized version, igbinary uses a binary format which is compact. This helps in brining down the storage size of the serialized data. This helps while trying to store the data in shared memory or memcache, which uses (limited) RAM to provide faster access to data.

Since I couldn’t find any pre-built binaries, I compiled the code which I got from their site. I compiled the 1.02 build.

Here are quick steps to compile this as a PHP extension for your system ( I tried this on Ubuntu, but should work on other distros as well). Uncompress the contents of the file to a directory and head over to the directory and run the following comands one after the other. Make sure there are no errors in each stage.

>phpize
>./configure CFLAGS="-O2 -g" --enable-igbinary
>make
>make install

If all goes well, the file igbinary.so should be present in your default php extension directory. Once you see this file there, head over to your php.ini file and add the following line at the end of it so that the extension is loaded with PHP.

# Load igbinary extension
extension=igbinary.so

Once you do this, restart your apache server to reload the PHP configurations. When you run phpinfo(), you should see the following lines in the output:

Once you’ve got that in your output, all you need to do is to substitute serialize with igbinary_serialize and unserialize with igbinary_unserialize in your code.

To see the differences in the two formats and see if the serialized and the subsequent unserialize I use the following script with some dummy data to print out the size of the output string of serialize and igbinary_serialize.

$arrc[3]=1;
$arrc[2]=2;
$arrc[0]=3;
$arrc[1][]="Testing";
$arrc[1][]="another data";
$arrc[1][]="structure";
$arrc[]=1;
$arrc[]=2;
$arrc[]=3;
$a = serialize($arrc);
echo "<br />size of Serialize :". strlen($a);
$b = igbinary_serialize($arrc);
echo "<br />size of igbinary :". strlen($b);

The output of this script came up showing that output from igbinary_unserialize does indeed use less space than the the output of serialize. Here’s the output of this script when I ran it:

size of Serialize :126
size of igbinary :74

If you want the igbinary functions to auto replace the default serialize in the PHP session handler, all you need to do is to add the following lines in your php.ini

# Use igbinary as session serializer
session.serialize_handler=igbinary

If you have any experience in using this extension on your projects, let us know your thoughts and observations. You can get more information on igbinary from the author’s site at: http://opensource.dynamoid.com/

Zend has launched the Simple Cloud project which allows PHP developers to write Cloud based apps without having to bother about the different cloud based solutions available. This works like an abstraction layer for various cloud solutions like Amazon, Windows Azure, Rackspace Cloud Hosting and a few more.

Initially this project aims at providing standard cross-cloud simple APIs for

• File storage- including Windows Azure blobs, Rackspace Cloud Files, Nirvanix Storage Delivery Network and Amazon S3
• Document Storage- including Windows Azure tables and Amazon SimpleDB
• Simple Queues- including Amazon SQS and Windows Azure queues

From Zend’s press release, “Zend Cloud will also provide adapters for local services to make offline coding and testing against cloud services as easy as connected development.”

These APIs will be appearing soon on the Zend Framework as the Zend Cloud component. They will provide the basic functionality across the various cloud hosting services, but if you do need vendor specific functionality in your code, Zend Framework will provide vendor-specific libraries as well. They’ve already got Nirvanix, Amazon EC2, S3 and SQS covered. Microsoft’s proposed the WindowsAzure services for Zend Framework. IBM and Rackspace are also working with Zend to get their services covered. With these integrations in motion, they estimate that ZendCloud adapter with these features will be available in the Zend Framework by end of Q4.

An initial Simple Cloud API proposal and reference implementation is available now for community review and participation at http://www.simplecloud.org.

Links:

Zend Press Release – Zend Teams with IBM, Microsoft, Rackspace and Other Cloud Leaders on Open Source Initiative to Drive Cloud Application Development
MSDN Interoperability Blog – Microsoft, Zend and others announce Simple API for Cloud Application Services

A few weeks back I had attended the Virtual Tech Days events, specifically the Interop sessions. I was quite interested in seeing what Microsoft had to offer for PHP developers. Going through the oveview of the programs, they seem to have come up with quite a few solutions for PHP developers. One of the important integrations for PHP is the ability to run PHP directly from IIS, as a FastCGI app, without having to install Apache in Windows.

To make this task of installing PHP under IIS as easy as possible, Microsoft has provided Microsoft Web Platform Installer, which helps you install PHP and other server modules required to create your Web Platform. To get started all you have to do is to head over to http://php.iis.net/ and click on the install blue PHP button there. That launches the Microsoft Web Platform Installer interface which installs PHP along with the required dependencies required. If you’re on Windows XP, you’ll need Service Pack 2 more above and .NET framework 2 on your PC. I was pleasantly surprised with the ease of setting it up. Even though PHP works under IIS 6.0, it’s recommended that you run PHP under IIS 7.0 since some of the additional modules you’ll need (like the URL rewriting) are available on IIS 7.0.

The Microsoft Web Platform Installer installer works on Windows XP, Vista and Windows Server 2003 and 2008. Apart from installing the server components on your system, this installer also gives you quick installation of popular web applications like WordPress, Moodle LMS and Acquia Drupal to get you kickstarted in creating solutions in PHP on Windows. To learn more about it, check out – http://www.microsoft.com/web/Downloads/platform.aspx

At this point most LAMP developers would be asking the question – But how will my existing application port over to the new platfom? Microsoft does provide a few additional modules which priovide the same functionality on IIS:

Rewriting the URL:

If you are looking for a functionality which is similar to Apache’s mod_rewrite, which allows you to create custom URL, here’s the answer to your problem. URL Rewriter for IIS 7.0 helps you create such custom URLs through rules on IIS. You can install URL Rewriter for IIS using Microsoft Web Platform Installer as well. For more information and links to documentations on this module head over to: http://www.iis.net/extensions/URLRewrite.You can also import your existing Apache’s rewrite rules into IIS using the URL Rewriter. Here’s an artice which shows you how: http://learn.iis.net/page.aspx/470/importing-apache-modrewrite-rules/

.htaccess rules in IIS?

Now how do you get all your .htaccess rules to work on IIS? To do this you’ll have to translate the rules which you created in .htaccess to IIS 7.0′s web.config settings. The web.config in IIS 7.0 uses an xml style syntax to define rules so you will have to translate you current .htaccess rules into this syntax. Here’s an article which helps you learn more on this process with examples to illustrate the transformations between the two formats- http://learn.iis.net/page.aspx/557/translating-htaccess-content-to-iis-webconfig/

PHP Extensions in Windows

Now to get those PHP extensions which you use and love working on Windows. All PECL extensions for PHP (pecl.php.net) should work on Windows if you compile them. If you are looking for pre-compiled versions of these extensions for Windows, pecl4win.com used to host them earlier, but that seems to be down as of now. You can get some of the (unofficially) compiled PHP exenstions at: http://downloads.php.net/pierre/

To install an PHP extension, you’ll need to download the dll file for the extension. Then find the path to your extension directory in your php.ini. The path to the extensions should come in the line starting with extension_dir. If this is not set in your php.ini, you can create a new entry by adding this line in your php.ini –

extension_dir = c:/php/extensions/

Now you can copy the PHP extension dll’s you downloaded to this folder. To enable the extension you have to add the a line in php.ini in the following format: extension = abcde.dll, where abcde.dll is the file name of the dll you downloaded to the PHP extension directory. Restart your webserver and check in your phpinfo() to see if your extension has been loaded.

Improve your PHP Application’s Performance on IIS:

Once you’ve got your application working on IIS, here’s how to supercharge it. To boost the performance of PHP on your installation, you should check out the Windows Cache Extension for PHP. One of the ways this extension helps your improve the performance of your PHP application is by keeping the complied PHP bytecodes in memory for faster access and resuing this for subsequent accesses to the same scripts. Caching the opcodes in memory also helps reduce i/o overheads required to fetch the php scripts when they are accessed. To learn more about Windows Cache Extension for PHP and the link to the Microsoft Web Platform Installer installer for this module head over to : http://www.iis.net/extensions/WinCacheForPHP

All these tools and modules does ease the work of developers who need to deploy their applicatons in Windows without much effort. Overall, Microsoft has come a long way in getting PHP applications working on the Windows platform.

One you’ve got PHP working in Windows, you can start using the other Microsoft technologies like Silverlight for PHP and the PHP SDK for Azure. More on these topics in the upcoming series.

Image Credits:
Lighthouse Image from:http://www.flickr.com/photos/derohlsen/ Licensed under CC BY-NC-ND 2.0

Some of the practices include in the article are “I don’t need no documentation” syndrome and “My code is the way to go” when other better alternates are out there. Why don’t you head out and read the full article there?

PHP Worst Practices

You can download Zend Framework 1.9.1 at: http://framework.zend.com/download/latest

The good thing about PHP 6 is that by default all strings are treated as Unicode characters, unlike the earlier versions where a lot of the default functions in PHP used to break up unicode characters and essentially junked the data. UTF-8 is now  the default encoding for many of the PHP 6 functions, so you don’t have to worry about your unicode data getting junked. In PHP 6 you have to watch out when you’re handling binary data, you’ll have to explicitly typecast your binary data or risk getting it junked because PHP 6 thinks of it as unicode

$binStr = (binary)$rawdata;

You can also declare the encoding of your PHP script by the following command:

Even your OO code where you were following the pre PHP 5.3 object models will not work here, since object model compatibility is removed. So your classes should be like this:

 class newClass {
   private $variable;
   public function myMethod {
    }
 }

instead of the old notation in 4.3 which used to look like this:

 class newClass {
   var $variable;
    function myMethod {
    }
 }

Read more on this topic at Linux Magazine: Get Ready for PHP 6

Image Credits: Narno via Flickr

• Locale — deals with breaking locale data into components, assembling a locale string from components and displaying the names of countries, languages etc in a specified locale.
• Collator — a means of comparing and sorting strings according to local rules.
• Number formatter — allows you to format numbers in a variety of ways, and to parse textual representations of numbers.
• Date formatter — allows you to format dates and to parse textual representations of dates.
• Message formatter — allows you to compose messages from parameterized strings while formatting the data inside according to local rules and allowing choices dependent on the actual parameter value.
• Normalizer — a means of bringing a Unicode string to a standard, unambiguous representation.
• Grapheme module – handles parsing a string into a set of graphemes.
• IDN – handles internationalized domain names format

Read Stas’ article to learn how to use the new features this extension provides to make your website Internationalization ready.

If you’re using PHP5.2, you’re in luck since there is a PECL package which should run on PHP 5.2.4 and newer over at: http://pecl.php.net/package/intl

Link: http://devzone.zend.com/article/4799-Internationalization-in-PHP-5.3

Image via Wikipedia