I have been developing PHP applications professionally for over 7 years. About a year ago, I decided to try developing some Ruby on Rails applications. My main Ruby on Rails projects have included an e-commerce site QuietHeadphones.com and an online application for synchronizing medical records with USB thumb drives. Of course, I have also worked with the Ruby on Rails blogging engine Mephisto which is what runs this website. So while I have worked with PHP for more time than I have worked with Ruby on Rails, I have worked with Ruby on Rails long enough to have noticed some significant differences between the two languages. My comparison is going to focus on the language differences between PHP and Ruby and not as much on the Rails framework.

There are rather significant syntactical differences between PHP and Ruby. For example PHP requires semicolons at the end of lines and generally requires curly brackets to enclose blocks of code. Ruby, on the other hand, uses newline characters to denote the end of a line of code and many code constructs such as function definitions, and various loops are ended with the word “end” rather than being surrounded by curly braces. Below is an example of PHP vs Ruby syntax.

PHP Function

function say_hello($name) {
  $out = "Hello $name";
  return $out;
}
Ruby Function

def say_hello(name)
  out = "Hello ${name}"
  return out
end

In Ruby, you don’t have to specify the return line as the return value of the last evaluated line is returned automatically. There are other differences in syntax between PHP and Ruby and, in general, Ruby is more concise yet it is not cryptic. Another general note about PHP is that PHP has a very large number of “built-in” functions – many more than Ruby. The Rails framework adds some nice helper methods for formatting dates, numbers, currency, and the like. PHP, however, has a vast library of functions that can do almost anything you will need. The naming of the PHP functions and the order of the parameters they take are somewhat inconsistent, but the functions are there making PHP an amazingly complete tool set for web application development. An example of the naming inconsistency is evident in function names such as strpos() vs str_replace(). Sometimes an underscore is used to separate words and other times it’s not. While that can be annoying, it’s something you can memorize in time and it’s not a huge deal. What really matters to me is what can PHP do that Ruby can’t and vice versa.

PHP5 was first released over three years ago, July 13, 2007. Frustratingly, and for various compatibility reasons, PHP5 is just now beginning to be an available choice on shared hosting accounts. Nevertheless, my comparison is between PHP5 and Ruby. Both PHP5 and Ruby have object oriented features albeit, Ruby is more sophisticated in terms of OO constructs. But I wanted to know what the real difference is between the languages. When I begin development of my next web application, what will I notice in terms of the differences between the languages.

The Similarities Between PHP and Ruby

Before getting started, I know that PHP and Ruby have very significant syntactic differences and different people may prefer one over the other. So it may be harder to implement certain features in one language over the other. Nevertheless both languages can do almost the same things. Both languages have try/catch/throw style exception handling. Exceptions are new to PHP5 as PHP4 does not have them. Both languages can be used in an object oriented way. Ruby has more powerful object oriented features but most developers probably won’t notice a difference in a normal web application. Both languages have additional functionality that can be added through libraries. In general, when developing web applications, I have not yet run into a time when I was working with one language and hit a road block where the language I was using was not capable of expressing the functionality I needed. Sometimes things are easier in one language versus the other but both PHP and Ruby have been able to “do” the same things.

About Frameworks

You can’t talk about Ruby for web development without mentioning Rails. Rails is fantastic and makes developing web applications much easier due to all of the built-in functionality. My favorite aspect of Rails is the ActiveRecord functionality. Often times, many of the objects in my applications are virtually empty except for inheriting from ActiveRecord. Validation is a breeze with Rails and is usually one line such as:

validates_presence_of :attribte_name

The built-in error handling with error_messages_for is very helpful. If you need more flexibility with the display of error messages, there are plugins to available for that. The ability to turn email sending on and off for testing is extremely nice. Having different configuration files for live, testing, and development environments is great.

PHP has over 40 different frameworks available. I’ve spent a significant amount of time studying PHP frameworks. The most popular ones appear to by CakePHP and Symfony. Both of these frameworks are essentially Rails clones. I think Symfony is the largest, and most comprehensive of the two. My favorite PHP Framework, howevever, is CodeIgniter. It is a Model-View-Controller style framework and has a strong Rails feel to it, but it is much lighter weight. CodeIgniter has no code generators like Rails has. It does have an ActiveRecord style Database class but it is not as powerful as the ActiveRecord in Rails. It is, however, quite nice and very helpful – much better than nothing. CodeIgniter, as far as I know, does not have anything comparable to Migrations in Rails.

PHP Does Not Have Formal Namespaces

PHP does not officially support namespaces and Ruby does. So organizing your code in a PHP application is something that’s left to the developer to figure out. PHP5 has the ability to autoload classess that are undefined. It is a very useful function and one that I have used to organize my code into name spaces. I essentially name classes with underscores separating directory names. Here is my autoload function that replaces underscores with slashes to create a path to the class files that I am using.

define("PROJECT", "/path/to/project/classes/");
define("LIBRARY", "/path/to/my/main/php5/library/classes/");

function __autoload($className) {
  $fileName = str_replace("_", DIRECTORY_SEPARATOR, $className) . ".php";
  if(preg_match("/^ProjectName_/", $className)) {
     include_once(PROJECT . $fileName);
  }
  else {
    include_once(LIBRARY . $fileName);
  }
}

I have a bunch of classes that I continually reuse in my PHP applications. The path to the root directory of my library is stored in the LIBRARY constant. Any classes I write that either extend my core library or are specific to the project I am working on get stored in the location specified by the PROJECT constant. This has been a system that works really well for me and is a good workaround for PHP not having namespaces. So PHP not having formal namespaces has not really hindered my development efforts.

Documentation

PHP kills Ruby and Rails when it comes to ease of finding, reading, and even generating documentation. The PHP website has wonderful, helpful, searchable documentation. The Rails Documentation is comprehensive but much harder to navigate and has far fewer code examples. PHPDocumentor also produces much better looking documentation that is easier to navigate than RDoc does.

Hosting Ruby (on Rails) Is Painful And Expensive

All the Ruby applications I have developed to date have used the Rails framework. So this is a comparison between hosting a PHP Application and a Ruby on Rails application. PHP has several good MVC style frameworks. My favorite is CodeIgniter and I’ll be posting an article about it soon. Using a framework or not, PHP is extremely easy to host. Locate virtually any hosting company, sign up for an account and start dropping your files on the server. I can’t say the same for Ruby on Rails.

I started off with a DreamHost account but performance and reliability were miserable. I ended up switching to a virtual dedicated server at Rimu Hosting and have been extremely please with their service. I’m running Apache 2.0 + Mongrel + ISPConfig and it’s working out nicely. But every time I want to deploy a new application I have to…

  • Set up a mongrel cluster
  • Configure 2 or three ports for the mongrel cluster
  • Create a map file for my random load balancer
  • Set up a way to restart the cluster if the server reboots
  • Configure Apache to forward requests to the mongrel cluster
  • Configure capistrano to deploy the application.

Fortunately capistrano handles all of the annoying tedium associated with deploying the application and restarting the server. So once capistrano is setup and working, future deployments are a breeze. Also worth noting, this assumes you have your source code in Subversion. So you have to make sure that Subversion is set up and accessible over the internet to the deployment server as well as your development machine. It is good practice to have you source code in version control and you should be doing this whether the project is PHP or Ruby. If you are not using subversion and, therefore, not using capistrano, deploy a rails application is very time consuming and frustrating. Lastly, you need ssh access to your deployment server if you are going to be using Ruby on Rails whereas PHP can be deployed entirely over FTP.

To have a reasonable and reliable hosting environment for Ruby on Rails applications, you should have a virtual private server (VPS) or a dedicated server. So that will cost you at least $50 per month. You can host multiple Rails applications on the same VPS but the RAM requirements for running the mongrel clusters will quickly catch up to you. While you could host well over 50 PHP sites running on your VPS you will only be able to have a handful of Rails applications.

Conclusion

I suspect very few people will argue that PHP is a more elegant language or is more powerful than Ruby. Frankly, Ruby is probably may favorite language that I have ever worked with and I have worked with Classic ASP, ASP.NET, VB.NET, C#, Java, and Perl all rather extensively over the years. Ruby is both highly expressive and concise which is rare and refreshing.

Rails is a very comprehensive and effective web development Framework and there’s nothing exactly like it in PHP. You get a huge amount of functionality for free. Developing in Ruby on Rails is also a very fast process because Ruby is a very concise language requiring much less typing than any other language I’ve worked with. CodeIgniter is a really nice PHP framework. It will give you a great boost when developing your next PHP application.

The hosting and deployment struggles with Ruby on Rails is a major sticking point for me though. As the owner of a web development company many of our smaller clients do not have the budget for their own VPS account and even if they did, we don’t have the staff to manage a large number of VPS accounts or dedicated servers. Keeping the security updates current, managing any issues that may occur with email, and all the other headaches that go along with managing your own VPS or Dedicated server is more than we care to take on for the relatively small, practical dfference between PHP and Ruby. For large projects, it may be worth the trouble, but for small to medium sized projects, PHP is much easier to deploy, less expensive to host, and the language is capable of taking on everything those types of sites require. For our projects, development time with PHP is not noticeably longer than with Ruby on Rails. Ruby on Rails integrates a lot of things for the developer.

There is ActiveRecord for managing the link between models and the database, migrations for keeping development and live databases in sync, built in testing, the ajax – prototype javascript library is included, and you get a well defined file system structure. While it may not all be packaged together as well, PHP can do all of the above.

Thank you for reading this and I would love to read your comments!