Tag Archives: Technology/Internet

Cool tutorial about Zend_Paginator

Every part of Zend Framework is indeed very profesional and useful. But as it happens often some modules are less used than others. Don’t know why but my feeling is that Zend_Paginator, a wonderful tool for pagination is really misunderstood. And in fact it does one of the most common web development tasks. It builds the abstraction for a component that everybody uses in a web project – pagination.

It make sense if there where more tutorials like the following one describing its usage! Many thanks to Joey Rivera for a great tutorial about Zend_Paginator.

Even more this tutorials goes behind the pure usage of the paginator but it helps you understand the integration with one of the most used web apps today – Twitter and another Zend Framework component – Zend_Cache.

joey rivera blog

Theory of caching. Zend_Cache & Zend Optimizer.

Although it may sound strange I’ll say why I’m using caching. Because it speeds up the site! Yeah there’s no other reason that may be so important as this is.

The caching is not a process invented in the last year, it’s useless to describe why do you need it, but however my intention is to describe how to make it work with Zend Framework.

The docs page of Zend_Cache is pretty clear about everything and I’ll describe the most important part of the cache setup.

First setup the cache back and frontend options. You need to decide where to save the cache files, how to cache them, and what lifetime do they need.

The most used cache configuration is, as you may guess, this one described into the doc page. Setup the front and backend options is just as simple as:

$frontendOptions = array(
     'lifetime' => 7200, // cache lifetime of 2 hours
     'automatic_serialization' => true
);

$backendOptions = array(
   'cache_dir' => './tmp/'
   // Directory where to put the cache files
);

// getting a Zend_Cache_Core object
$cache = Zend_Cache::factory('Core',
                             'File',
                              $frontendOptions,
                              $backendOptions);

Because all this is well described into the doc page, which you can found here I won’t talk about it. But I’ll talk only about one sole thing. How much the cache must live? What should be its lifetime.

The answer is simple. If you have some basic statistic of your site traffic and you don’t change much the data you can prefer longer cache period. But imagine the site’s making 1000 visits per minute! Than even if you cache every minute and the cache expires every minute will be a success and the user perception will be really great. From those 1000 visitors only few will wait until the cache’s built and the other hundreds will receive really fast response!

Be careful when you cache only because you can overflow the directory where you cache, which will be difficult though.

In other way many people are thinking about Zend Optimizer and its work with Zend_Cache. These are really different things. Zend Optimizer has nothing to do with your code it is a PHP caching tool. As you may know PHP interpreter mingles the code into “machine like” code, which in turn can be cached into the RAM with the help of Zend Optimizer. Checkout more here.

Using Zend Framework validators – Zend_Validate_Db_RecordExists

What are validators?

In very very breve these are methods which can validate some data, usually user input, against some specific rules. Imagine there’s a web form that is always checked for empty fields or some fields that may contain valid e-mail addresses. This is so common that became everyday routine to almost all of us. However smart developers make abstractions that help them reuse all this functionality. Even smarter developers make use of frameworks. And for those of you, using Zend Framework, there’s no need to write most of the common used validators, simply because they come with the framework itself.

Technically you’ve various validators in zend, such as Zend_Validate_Alnum, Zend_Validate_Email or Zend_Validate_Regex. All these are extremely useful when it comes to automatic, bullet proof validation, but I’m going to talk more about one specific validator.

Zend_Validate_Db_RecordExists

Although the implementation is nothing more than just a chunk of code and doesn’t pretend to be difficult, the idea of such validator is genius indeed. It really helps you do some amazing job.

Image you have to check some database record existence. Then comes in help this validator. In fact I’m pretty sure almost everyone has experience with such kind of task. Simply because the registration process almost always requires it. When you try to register new user you more often check for the username existence. Although you may solve the problem with other technique by catching the exception the database is throwing for duplicate entries, this should be assumed just as an example.

I’m pretty sure this validator can be really useful in many occasions!

YouTube and Vimeo goes HTML5 with video tag usage! Catch them up!

What better example than that coming both from YouTube and Vimeo. Although video tag is not supported except under Safari and Chrome, that’s the future everyone’s going to embed sooner or later.

And if these “big players” are going that way, don’t hesitate to follow them! HTML5 is really what we as web developers were waiting for so long and even all of the problems during its standardization process it’s really cool there will be tags like video.

What YouTube is doing today, perhaps will seem normal to everyone tomorrow. However there are some questions still with no answer, as where the flash possibility to add ads into the player is going?! But we’re about to see great things from these two sites!

Just check out these two links:

Youtube HTML5

Vimeo

What’s groovy in Firebug 1.5

Now Firebug 1.5 is out in the wild. What really impressed me is the significant difference between the last version and the really user friendly interface it gives.

One of my favorite features is that you can now sort the different columns in the Net panel. Now you can clearly see what’s the biggest component and what makes more traffic. This helps a lot once you decide to optimize the web page you’re watching.

Another good tool is that you can see the computed style, which however is only for Firefox and gives you partial information about all styles in different browsers, but it’s useful though.

I was pretty impressed by this version and I’d like to recommend it!