On his web development blog, Joey has posted a new list of eight handy regular expressions you can use in your code for common validations.

Here are eight examples of practical PHP regular expressions and techniques that I've used over the past few years using Perl Compatible Regular Expressions. This guide goes over the eight different validation techniques and describes briefly how they work. Usernames, telephone numbers, email addresses, and more.

Each of the regular expressions comes complete with an explanation of what it is and the kinds of strings it's looking for. Comments on the post have helped even more, finding places where they might break or not catch all possibilities.

Andreas Gohr has posted some info and code about one of the social networking/linking services out there, StumbleUpon. His post includes PHP code to figure out what your site's StumbleUpon ranking is.

StumbleUpon recently(?) added a "search result enhancement" feature to their toolbar. It adds StumbleUpon "star ratings" to Google results (See screenshot). This got me interested and I had a closer look at their extension...

As part of this "closer look" he came up with the code to return a general ranking for the URL you would give it. It does require a StumbleUpon auth key and username, but if you use the service already, you're one step ahead on that.

The IBM developerWorks site brings the community another great tutorial today, this time looking at the CakePHP framework and the creation of a simple application with it.

In "Cook up Web sites fast with CakePHP, Part 1: Adding related information and services", they build a sample application (Tor) from the ground up (installation guide and all) that will take in a username and password on a login page. Their goal is to show you how much time you could safe by using the framework over just the usual library-based (or procedural) programming methods.

You will need to be a bit familiar with PHP and the Model/View/Controller design pattern before you get started here, but if you have that down, you can just jump right in. You'll also either need to register with the site or log in with your account information to get to the good stuff.

Ryan Malesevich is taking a break from his look at some handy WordPress packages to share a small series on how to move from using MD5 hashes out to SHA-1 hashes for passwords in a MySQL database. He's posted part one today.

What if you're using MD5 in your web application and want to switch over to another encryption method. It's actually not that hard and I plan to cover them in this multi-part tutorial (I know I planned on writing this months ago, but it's better late then never). In this first part I plan on going over updating the database structure and a 'pseudo-code' of what will need to be done.

As mentioned, he gives the outline (pseudo-code) of how the process will work - basically, creating an SHA1 hash of the MD5 and the username in a "newpassword" column added to your database.

Encryption can be a difficult issue to comprehend, inside of PHP or not. Thankfully, there are resources out there that can help simplify things and bring them down to where they're really useful. This new tutorial from the IBM developerWorks site today is just such a resource.

In this increasingly virtual online world, you have to be careful to protect your data. Learn the basics of encoding and encrypting important bits of information, such as passwords, credit card numbers, and even entire messages. Get an overview of what it means to encrypt and decrypt information, as well as some practical examples involving passwords and other data, using PHP's built-in functionality.

They start off where any good encryption article should - with a primer in cyrptography. You can't understand the advanced without a good grasp on the basic. Using this knowledge, they start to work up their form, a simple username and password validation system.

They provide all of the code you'll need to build the form, and even intorduce you to the crypt() function. A bad use of this functionality is also illustrated. Of course, encryption is only half the fun, so they also include an example of decrypting the same information.