PHP Fog is a platform-as-a-service offering that, as its name suggests, targets PHP-based applications. The PHP Fog service, alongside a handful of other new services, fills what has been a gap in the PaaS market, as the best-known PaaS offerings target other languages, chiefly Java, Ruby and Python.
The service, which became publicly available in May, layers caching, load balancing, database scaling and code version control features atop the Amazon Web Services foundation that the service taps for its underlying infrastructure.
The service provides for elasticity by enabling users to spin up multiple Amazon EC2 (Elastic Compute Cloud) instances to serve customer PHP applications from behind a load balancer. This scaling, however, does not occur automatically-users must scale the number of active servers up or down manually, through the PHP Fog Web console.
Each subscriber cloud gets its own set of EC2 instances, with MySQL database service provided from scalable, multitenant MySQL instances. For those who'd prefer dedicated MySQL instances, PHP Fog supports the use of separate Amazon Relational Database Service instances.
Developers interact with PHP Fog using the distributed version control system Git. During my tests, I created and uploaded an ssh key for use with the service. I used the key to authenticate with PHP Fog for pulling and pushing PHP code with Git.
The service includes a handful of "jumpstart" templates for getting up and running with popular applications and frameworks. These templates enable developers to get up and running quickly with WordPress, SugarCRM, Mediawiki, Joomla and Drupal, as well as with CakePHP, Zend Framework and a few other PHP-based frameworks.
PHP Fog's first service tier, called the silver cloud, is based on micro-sized EC2 server instances, can be used to host up to 10 separate applications and is priced at $29 per server per month. Pricing is prorated per day, so a customer can opt to scale up or down as needed, and pay accordingly.
PHP Fog offers two additional tiers: gold and platinum. The gold tier is based on small-sized EC2 instances, supports 30 applications at a time and is priced at $79 per server per month. The platinum level is based on large-sized EC2 instances, supports 125 applications and is priced at $249 per server per month.
There's also a free, shared cloud option, which supports one application, offers no additional server scaling and must be upgraded to a paid tier after six months. Still, the free tier is worth checking out for those interested in trying out the service.