The PHPro.org website has this new tutorial posted today - a step further into the would of OOP in PHP with a look at abstraction, hierarchies and polymorphism.
The PHP Object Oriented method of programming brings many exciting possibilities to application code. Many of the theories surrounding PHP Object Oriented code comes from some simple concepts. To the new comer, some of these concepts seem a little abstract, and with good reason. Abstraction is a key concept on Object Oriented code, but to the un-initiated, may seem rather vague.
Kevin looks at creating abstract classes as a foundation for types other classes can work from, overriding built in classes (like extending the DirectoryIterator to make a DirectoryReader class).
DevShed continues their look at custom exception handling in PHP5 application with this third part of their series, a look at handling exceptions from MySQL calls.
Having already introduced you to the main subject of this article series, it's time to summarize the topics that were discussed in the last article, in case you haven't read it yet. In that particular tutorial I explained how to implement a fully-functional customized exception system with PHP 5, which came in handy for handling a number of specific exceptions thrown by a basic MySQL abstraction class.
They create a custom MySQL exception class that sits on top of their MySQL abstraction layer (and Result handling class) and catches exceptions thrown from sample queries.
Henrik waves goodbye to the Zend_Db component of the Zend Framework in this new post to the ProDevTips blog - his new favorite is Doctrine.
It was long overdue but finally I've taken a look at Doctrine. And I'm blown away, bye bye Zend DB. [...] It's time to try and convey how awesome I think Doctrine is.
His example sets up a table definition and defines the associations between the columns for a "members" table. He defines a "city" table too and shows how Doctrine can easily combine the two and make selecting from and inserting into the tables simple.
The ThinkPHP blog points out a milestone for one of the libraries that help set PHP on its current course - PHPLIB (from Kris Koehntopp).
This great collection of classes was in my eyes the first real useful library which delivered the solution to most of the basic / standard problems in PHP based software projects. [...] The easy implementation of DB-abstraction, template engine, authentication, permissions, session management and others made it easy to handle these problems in a standardized way. The strict object oriented code gave the developer the necessary flexibility to customize and extend the code where he/she needs it.
This year is (about) the ten year mark for the existence of the language and several commentors on the post remember the "good ole days" of PHP3 sessions, permissions and even the first version of Zend's website.
A different sort of abstraction layer project has been started up and has already seen a few releases - Forage. As mentioned on Rob Young's blog:
Recently I've been working on a search abstraction library for PHP called Forage. The idea is to bring to search what we've had for relational databases for quite a while, abstraction.
On Friday I put up a preview release with three backends; Solr, Xapian and Zend Search Lucene. At the moment it has the bare minimum of features but there will be more soon. In this post I'm going to talk a little about the motivation for the project and then walk through a short example.
He talks about the need for search abstraction (integration and resilience to change) before getting into an example of some code that grabs the data from an RSS feed, passes it in to the Xapian search engine and stores it before looking it over for thier search terms ("yahoo microsoft").
On the PHPClasses.org website there's a new entry covering, among other things, one handy feature PHP includes to let developers read and write their data more flexibly - streams.
This article explains what are stream handlers and how they simplify PHP developers lives by allowing PHP applications to easily read and write data from containers, like remote Web pages or e-mail messages, as if they were files. [...] The article also presents more examples of cool stream handlers classes submitted to the PHPClasses site by several authors.
He describes the abstraction that the streams interface allows, how they can make your life easier, a real-life example of streams in action (working with POP3) and some of the classes that have been contributed to PHPClasses.org that use them.
The Zend Developer Zone has posted episode 34 of their PHP Abstract podcast series from Manuel Lemos covering the abstraction of steams in a PHP application.
Today's special guest is Manuel Lemos of phpclasses.org Manuel is from Portugal and currently lives in Brazil where he works full-time on PHPClasses.org that he created in 1999. Today, Maunel is going to talk to us about Streams Abstraction.
Grab it in one of the usual three ways - listen on the page, download the mp3 or subscribe to feed for the show. Also, be sure to check out some of the other episodes listed at the bottom of the post for lots of other great content.
On the Zend Developer Zone, jonwage has posted about an ORM (Object-Relational mapping) he came across that can help abstract out your interface with your backend database - Doctrine.
One of its key features is the ability to optionally write database queries in an OO (object oriented) SQL-dialect called DQL inspired by Hibernates HQL. This provides developers with a powerful alternative to SQL that maintains a maximum of flexibility without requiring needless code duplication.
The project's page gives the full details on the features it offers and has links to the latest downloads so you can try it out for yourself. There's even a blog you can subscribe to to keep up to date.
Wez Furlong posted a request for comments to the php.internals and php.pdo mailing lists yesterday about a new ly proposed update to the current PDO functionality - PDO 2. He just wants to clear up a few things...
It became apparent over the past year or so that PDO has been a good and
valuable addition to PHP. [...] We believe that having direct involvement from the data access providers would be most effective, which is why we set out to try and get them on board.
There were three steps they would need to make to push things to version two (documentation, define scope/direction and organize data provider integration methods) and the proposal that has caused a huge stir in the community - the idea of requiring a CLA contributors would need to sign.
Comments to this point from the community include:
David Coallier has posted about a database abstraction layer that he's been developing for PHP 5.2.x only systems and wants some opinions on his methods:
I made a very light DBAL that uses PHP5.2.x only (Since many people seem to want that) and it has the exact same DSN syntax as MDB2 for now and the query method are also called the same (No API Changes). [...] The main goal of the DBAL is to have a very effective and light way of switching RDBMS but also the possibility to change your DBAL to something more "0feature complete" as such as MDB2.
He includes the list of query method names and the types of databases that he wants it to support (as well as mentioning the fact that it would be unit tested for reliability).
